In Starland with a Three=Inch Telescope a Conveniently

Home , Fermat (crater)

In Starlan d

With a Three = In ch Tel es cope

A Conveniently Arranged Guide fo r t he U s e o f the

Amateur Astronomer

- W ith Forty Diagrams o f t he C onstellations and

Eight o f the M oon

William Ty ler Qlcott

“ Author of A Field Book of the Stars O P YRI GH T 1 0 C , 9 9

B Y WI LL I A M T YLER OLCOT T

t he k nick et bock er pres s , n ew mot h I NTRODUCTION

HE s ole purpos e of this book is t o afford a c onvenient guide for th e amat eur ast ronomer when engaged in 0 i s o t el es c p c Ob ervati n . ’ s o st of t h e oo s s t h e s A ide fr m a udy m n urface , Ob erva tion of double st ars is s ure t o prove th e mos t att ractive

for h e os s s o of o t work t p e s r a s mall t ele s c pe . The brigh er

o s th e o no f t i d uble n vice will have di ficul y n finding , bu t t hos e below t he t hird magnitude are O ften difficult t o locate wit hout reference t o a diagram of th e con st ella tion of which it is a part - hence t h e aut hor h a s s een fit o s it s o s t t place uch a diagram where can be ea ily c n ul ed . It is pre supp os ed t hat th e owner of t h e t ele s cope is

h o o s I t s o familiar wit h t e c nstellat i n . t hen h uld be an

s tt t th e s s st o f t h e o ea y ma er , wi h a i ance acc mpanying

o ﬁnd he o s s t o t h e s t t t t t . diagram , d uble ar men i ned in ex The con stellation s are grouped under t h e s ea s on s for th s of o e ake c nvenience .

of t h e st s t o o s of th e t Many ar have fain c mpani n nin h ,

t t or t t s . s o s t en h , fain er magni ude The e d uble are in er

st s o t o t os w h o s t o t st t s t e ing lely h e de ire e heir eye igh , or t h e o s of t s s s o t a s p wer heir gla . They are di app in ing c ompared wit h t h e beautiful double s t h e magnit ude O f os o t s o on s a s wh e c mponen are m re nearly a par , uch iii

2 117 7 4 Intro du ctio n

s o o s h as C t s . t o t a r , (y) Le ni ,(y) Virgini The au h r here o t h e o s t o ot s o t t t os os f re arranged d uble be n ed , ha h e m t wo rt hy of Ob s erv ation c om e first in the column as s igned t o t hem . The chapter on the moon is arranged according t o th e s a s th e tt on th e o s t s co s s s ame idea ma er d uble ar , nci ene

t s at s s and brevi y being e pecially aimed . The plea ure of s o s o s t t t th e t o s elen graphy are fa cina ing , ha au h r feel a s s ured t hat th e student will add t o t h e brief outline o t th e r here given by c lla eral reading . Only p incipal object s of int ere st are mentioned in t h e t ext accompany in s s s of th e oo O s g each ucce iv e View m n . The b erver will n ot e a wealt h of det ail in every peep he t ake s at the m oon t hat will add greatly t o his plea s ure

’ o t th e m is on d étre of th e oo is con In a w rd , hen , b k v enience of t o h a s o arrangement . The au h r f und by ex perience t hat what t h e st udent m ost needs when he is s t th e t s o is t o at t t Ob erving wi h ele c pe , a page glance ha s a s t o t h e o t h e s s t o will erve a guide bjec de ire view , and

f o s o s t which a f rd c nci e dat a rela ive t o that object . The ’ s t o t th e st t s s o th e s u b diagram heref re direc uden vi i n , and ect tt afford s the c s s o t o in s j ma er ne e ary inf rma i n each ca e . t t t t s o t s o s u s e com The fac ha here are few ele c pe in ,

arat iv el s n t s o t s for the p y peaki g , in a grea mea ure acc un

tt nt s t s t o o t th e li le i ere in a r n my aken by public . I f t he s e page s s erve t o awaken t he s light es t int ere st in th e

s t st of th e s th e t o fa cina ing udy heaven , au h r will feel amply repaid . THE DI AGRAMS OF THE CONSTE LL ATIONS

HE diagrams repre s ent th e appearance of th e con

s t ell ations t h e s s o t in ea n in which hey are placed , and favorable location for ob s ervat ion w a s chieﬂy con

s s id ered in t hu s grouping t hem . The tudent can vary

o his o th e arrangement t s uit c nvenience .

As th e t is th e s t s t for s t - win er lea de irable ime ar gazing , th e great er number of con st ellation s h ave been purp os ely

o h e o s o gr uped in t t her s ea n s . The s o-called circump olar const ellation s are of

o s for o s t o a t t of t h e c ur e available b erva i n any ime year , and the s tudent can ch oos e his ow n t ime for s t udying

t hem .

At the oot of of o st t o for f each diagram a c n ella i n ,

s t h e o f ready reference , appear name and page number

o o s o i the c nst ellati n b unding t . Only th e const ellat ion s vis ible in th e latit ude of th e New E ngland and Middle St at e s have been included in t oo his b k . The aut hor pre supp os e s that the t ele s cope t o be u s ed in

o t o t t s - oo is n ot t s c nnec i n wi h hi b k equipped wi h circle , otherwis e rec ours e s h ould be had t o s ome s uch b ook a s ’ s Celes ti a l Ob ects or Common Teles co es for o Webb j f p , a m re

V vi The Diagrams O f the Co ns tell ation s

t o t o of th e o t s of t st t s of exac l ca i n bjec in ere , in erm

s o Right A s cen i n and Declination . F or t h e m ost part only d ouble s t ars wit h a primary of t h e s t t or t a s it is ix h magni ude brigh er are given , difficult t o direct t h e t ele s c ope at a star of le s s er magni

s s i s o o i o t ude unle t p s it i n s accurat ely kn wn . In s earching for double st ars many faint y et beaut iful s t s o s s o t t it is t o pair and riple are b erved , ha well have

’ s oo a s s o t t t s o t s uch a b k Webb , in rder ha he e bjec

can be identiﬁed .

s o t o st s The diagram include ver hree hundred d uble ar , and th e s ight o f t he s e and th e many ﬁne clu st ers and nebulae mentioned s hould afford t h e happy p os s e s s or o f t s o o s of o t a ele c pe many h ur keen enj ymen . Con s iderable dis crepancy will be n ot ed in the c olors

a s s n t o t he o st s t os o s . ig ed d uble ar , and h e b erved The

o o s s is a t st s t o c l ring in many ca e be elu ive , and a m s pheric conditions and peculiaritie s of Vis ion play an

i o i of mp rt ant part in determining t . In a number ca s e s t h e colors are very pronounced and render t h e

t o f s s s t a s for st t he t Objec urpa ing beau y , in ance in grea o t C st o o is t t of th e fav ri e (B) ygni . The ﬁr c l r given ha

or t st s t the s o o o is t t primary brigh e ar , ec nd c l r given ha

of t h e o o c mpani n . The p os it ion angle meas ure s the inclination t o th e of o h o I meridian a line drawn t hr ugh t e d uble st ars . t

s o s th e o s t o oo for th e o o st h w b erver where l k c mpani n ar ,

is o o 0 s t o 6 0 s and reck ned fr m degree 3 degree , beginning The Di agra ms O f the Co ns tell ations vn

a t th e o t o n t an d o t o th e s t n r h p i , pr ceeding hr ugh ea ,

s o t st t o th e o t . s t t s o u h , and we n r h The uden h uld bear in mind in t his connect ion t hat in t h e t ele s c ope t h e no rt h

and s out h p oint s are revers ed . The decimals are omitt ed from t h e di st ance s given

t t h e o s o t t o t be ween d uble (which are fr m cen re cen re , and

s o s o a s t h e o s a s o s t of in ec nd f arc) in wider d uble , m t os t o the t t o t s o t h e referred in ex w uld be ermed , ab lu e

s t s for o s s o f s tio accuracy in mea uremen , purp e Ob erva n is non - s s t purely , e en ial . A t hree -inch glas s s h ould s plit st ars t hat are di s t ant ” o o 2 o s s s t o of s tt fr m each ther . 3 Of c ur e t hi que i n pli ing double s depend s in a great meas ure on t h e p ower of t h e

s t he o t o of t h e t os t h e eyepiece u ed , c ndi i n a m phere , and

. of h e o s s recom qualit y t eye s ight of t h e b s erver . Servi mend s a p ower of from ﬁfty t o s eventy t o t h e inch o f

t o h a s s s t h e aperture . The au h r ucceeded in eeing great maj orit y of t h e double s ment ioned in t h e t ext wit h a

o of 1 0 p wer 3 . “ The t erm light year which is us ed in th e t ext is th e u s ual t erm for expre s s ing t he di stance from th e eart h t o h t st s . t is t he t of s s t s e ar A ligh year uni u ch mea uremen ,

is s th e s t t t s in th e and imply di ance ligh ravel a year ,

s of t 1 8 6 c c o s s o E s s peed ligh being , mile per ec nd . xpre ed in ﬁgure s it gi ve s a s th e di s t ance

s t t t t s one i in mile ha ligh ravel in year . When t is

‘ t t 6 1 C th e e st s t t o t h e t added ha ( ) ygni , n are ar ear h

t h e o t s is s ix li ht i ea rs in n r hern hemi phere , nearly g y v iii The Diagra ms o f the Co ns tell a tio ns

s o of t h e o t of s is a away , me idea pr fundi y pace m de manife st . The following s ymb ol s are u s ed in th e diagram s "

o t t o t t h e o s s O The u lined circle indica e d uble t ar . The cros s t o indicat e th e p os ition of th e a nebul e . The group of dot s t o s how the location of th e s tar clu sters . The following abbreviations appear in th e t ext A D H M . . st . s . t , Angle ; , Di ance ; , Her chel ; g , Magni ude M m 0 Pou lk ov s 2 . a t o . s t 22 C , Me ier ; , W S ruve ; , a al gue , ’ P i O o t t E tt t . Par I I ; Piazz Smy h ; , O S ruve

In th e compilat ion of t his book I de s ire t o acknowledge

t s s t o . tt . s s th e t o my indeb edne Mr Garre P Servi , au h r

f he M oon l u r th T l s o e s oo s o T and P eas es of e e e c p . The e b k

os t s t o t o t h e st t have been a p i ive in pira i n me , and uden

o is urged t o include t hem in his c llat eral reading .

s s t o n o one h a s o o t o O u Mr . Servi , han wh m d ne m re p p l a riz e t h e st of t h e s t s h a s th e o charming udy ar , w nderful gift of impart ing kn owledge t hrough th e medium of a s t t t is t o t s t t t yle ha al ge her fa cina ing , and I ake grea pleas ure in adding my mit e of t ribut e t o one w ho h a s affo rded me t hrough his numerou s writ ings s o many

o of o h urs unall yed pleas ure .

“ t h e s t of o t s s t for o s t o In preparing li bjec ui able b erva i n , I derived much valuable information als o from th e fol lowing book s The Di agrams of the Co ns tell atio ns ix

Celes tia l O bj ects for Common Teles copes H a lf H ou rs w ith the Teles cope H ou rs w ith a Three-inch Teles cope Noble P opu la r Teles copic A s tronomy Fowle r A s tronomy w ith the Nak ed E y e Servis s

The M oon o t o , Pr c r

The F riendl S ta rs Mr y s . Martin

’ K lein S a r A tla s s t .

’ B a ll s A tla s o A s tronom f y . The Nau tica l A lmanac .

CO NTE NTS

PAGE INTRODU CTION TH E DI A G RAM S

The Cons tellations Spring.

CA NC E R A ND CA NI s MINOR CO R ON A B o R E A L I s

CO RV US A ND C RATE R DRACO

HERCU L ES

LE O

LY RA VIRGO

’ S The Cons tellations of ummer.

B oo T E s

CA NE s VE NAT I CI A ND CO M A B E RE NICES

L I B RA

OP H IUC H U S A ND S E RP E NS

x i Co ntents

PA G E S A GITT A A ND D E LPHINU S SAGITTARIU S

SCORP IO

URSA MA"OR URSA MINOR

Th e Cons tellations of Au tumn .

ANDRO M EDA A ND TRIANGU L U M

AQUARIU S AQUILA ARIES AU RIGA

CA P RIC ORNUS CASSI O P EIA CE P H EUS CE TU S

CYGNU s

PEGASU S AND E QUU L EUS P ERSEUS PISCES TAU RU S Co ntents

PA GE

Th e Cons tellations of Winter .

CA NI S MA"O R E RIDANU S GE M INI

L E P U S M ON OCE ROS ORION

The Moon .

— A L PLATE I . S H ow 1NG T H E MOON D Y S O D

— L D I I . S H o w 1NG T H E M OON D AY S O

— D I II . SHO W ING T H E M OON D A Y S OL

— D IV . SHO W ING T H E MOON D A Y S OL

— L D V . SHOW IN G T H E MOON D A Y S O

— H L D VI . SHO W ING T E M OON D A Y S O

— L D 1 0 2 VI I . SHO W ING T H E M O O N D A Y S O

— A VIII . SH O W ING TH E M OON D Y S OL D

S O F U A S F M E . 1 0 LI T OCC LT TION RO S PT I , 9 9 , TO

A N . 1 1 1 " I , 9 Conten ts

PA GE TH E PL A N E T S M E RCU RY VE NUS MARS

j U P I TE R

’ PH E NO M E N A OF JUPIT E R S S AT E LLIT E S DU RING Y G S 1 0 TH E Y 1 1 0 1 1 8 "U L AND AU U T , 9 9 , AND EAR 9 E " P L ANATO RY DIAG RAM O F T H E P H E NO M E N A oE ’ JUPIT E R S S ATE L LITES SATU R N URANUS A ND N E PTUN E PL ANETARY D A T A AND D IAG RA M SH O W ING T H E PO S ITION S O F TH E P L A N E T S ON T H E E CLIPTIC "ANUARY 1 s t F O R TW E LVE YE ARS

TH E SUN

IN DE " T H E C O NS T E L L A T IO NS O F S PRI NG CANCE R AND CANIS MINO R

R E M A R K S

l u e . Yellow , b o t t Go d con ras .

Only tw o stars ca n be seen wit h three-in ch

glass .

Use 1 6 0 power .

u Gold , az re .

In Canis Minor .

th t I t c t Observe e Bee Hive wi h a low power . on ains t 3 6 3 s ars . Note th e clu ster 1 7 1 2 ( 6 7 Herschel observed more t han 0 0 t in th e V i a t 2 s ars field of ew once . t t h t u An occu l a ion of (7 ) by t e moon freq u en ly occ rs . See t u t t Lis of Occ l a ions , page c t o 8 u u 1 2 . ( ) was discovered be do ble by Herschel , 7 Beca se ’ o f t h e u t t t in 1 1 0 m ch an icipa ed reappearance of Halley s come 9 , it is an interesting fact t hat t his comet was first observed in in 1 1 Cancer 5 3 . t t t u t in Observe Cas or , ha gem of do ble s ars Gemini . t th e t a 1 0 th tu Procyon , a s ar of solar ype , has magni de com ” i 8 t I t is t d is n 2 1 t . 1 2 panion , green color , dis an ligh years t t t 1 I t is not an , and has a proper mo ion of 3 miles per second . d efinitely known whether it is approaching or receding from th e t ear h .

CORONA BO RE ALIS

R E M A R K S

t u Whi e , bl e ,

green .

t u e D t t No e a naked eye do bl . is ance , angle , Bo h ot h t C t oo f u t deep yellow . They b h ave a fain ompanion di ﬁc l o for u r glass . marks the S pot where a famou s temporary st ar appeared 6 t t h t u u t tw o in 1 8 6 as a s ar of e second magni de . n abo weeks I . t o t h e t it s t t u I t wa s t h e t it . declined nin h , presen magni de ﬁrs t t o t w a s temporary s ar which spec roscopic analysis applied . According t o Webb t his st ar s ltpu ld be carefu lly wat ched 1 ou I t is n The st ar ( 1) is t oo close a double for r glass . a bi ary t t I t is t t t o o a t wi h a shor period . Webb says , in eres ing lo k so wonderfu l an object as a pair of s u ns revolving in th e brief ” period of years . R marks one of t h e most remarkable variable stars in th e

” It i t a t u t t heavens . rema ns some imes for year wi ho any al era

t in t t . I t ion ligh , some imes falling rapidly varies from a magni t o t h th t u de of e 1 3 . t t h e u in s ot in t s t " No e do bles Serpen and Bo es hi locali y as ’ nt r indicated o he diag am . CORONA BOREA LI S

Gemma

Ser pens Page 27 Bootee Page 21 Hercu l es Pa ge 11 CO RVUS AND CRATE R

C O R V U S

A NGL E R E M A R K S

u Yellow , p rple . t t Fine con ras .

t k i in 8 At No e ( R) recognized as a variable by K a rl ins 1 6 7 . u it th e t t u t o th e maxim m reaches seven h magni de , declining t t u e 1 s . leven h magni de . Period , 3 9 day Observe t h e neb u la 43 6 1

R E M A R K S

This st ar is in

Hydra . — u t t v is u 2 1 t u 8 i . D s J s wes of ( ) a do ble ( 4 7 Magni des , 9 ° t 1 0 ance , Angle , ’ 2 1 t is t u s -8 t nor h Magni de , 7 . Dis ance , Angle , O

t o a tt o it s t A line drawn from ( ) , prolonged a li le ver leng h , locat es a remarkable planet ary neb u la in Hydra (Herschel I t u i l t h e t u t will be seen like a pale bl e d sk , ike ghos of J pi er . t is u t u t u t u t ae I j s so h of th e fo rt h magni de s ar (ﬂ ) Hydr . CORVUS AND CRATE R D RACO

DI S TA N C E A N G L E R E M A R K S

t A grand objec .

e V ﬁne .

ite u . W , bl e , red

t A ﬁne S igh .

Orange , emerald . d R e u . , bl e o o t s t G d con ra .

’ t o A s riking bject . u Yellow, bl e . t t Bo h whi e . A beau t ifu l m in ' ia t u re of Cas

t or .

’ t u t tl e s u 1 No e T variable neb la 4 4 5 . ' u f A th u t 2 1 Look so t h o ( ) a degree for e do ble s ar 5 73 . Mag — - nit u d es 6 1 t , 3 7% Dis ance , Angle ,

t o o is ti u e According Flammarion ( ) an op cal do bl . I t is an interesting fact that th e st ars which are n ot visible t A rox i t o t h e eye give more ligh than t hose which are visible . pp

t t 2 0 t s t h e 1 s t t u 6 0 ma ely speaking , here are s ar of magni de , of

. t i t h u th e 2 d 1 8 0 t h e d . u i , of 3 , and so on M l ply ng e n mber of stars of each s u ccessive magnit u de by 3 gives th e n u mber of th t t t u stars of e nex fain er magni de .

8 DRACO

0 02 2 123

0 2 1984

P ol aris H E RCULE S

R E M A R K S

range , green . oo d t t con ras . u Green , p rple . t Whi e , lilac . t r Bo h g een , ' coloring ﬁn A l e ree p g , cpl e l y reni l owr d Y e l ze .

P tt ou re y d ble .

e u t A b a y . Dist ance slowly I ncre a s In g .

t h e u u iu u For do ble (m) Herc les see Oph ch s . u t a u u t o The cl s er 4 2 3 0 (M . I s perb globu lar cl s er disc vered in 1 1 is l th O ti t by Halley 7 4 , wel wor bserving . Herschel es ma ed t t it o t t I t t u - t o ha c n ained s ars . akes a fo r inch glass c t th e t th e t a ch winkling of s ars . According t o Herschel and Argelander th e solar system is t A moving oward ( ) . 6 IS a one t t t ( ) colored variable and ha will bear wa ching .

a is t t h e t t t . ( ) a red s ar , one of ype wi h banded spec ra A circle described with (p) as a centre and a radiu s a li tt le greater t han t h e dist ance from (M) t o (A) incl u des t h e resu lt of ﬁve st andard u t t t h e t h e t —th e t comp a ions for apex of solar sys em , poin t oward which th e s u n and all t h e planet s are speeding a t th e t 1 ra e of 4 5 miles per s econd .

I O

DI S T A N C E A NGL E R E M AR K S

Finest do u ble in t nor hern sky , according t o

Stru ve . t u Lemon , ligh bl e ; a second pair in th e ﬁel d ( 8 3 ) ” i t A ﬁne s gh .

u u is t t t i Reg l s 3 5 ligh years dis an from th e earth . Accord ng to H u ggins it is receding a t t h e rate of t welve t o sevent een miles

. I t t t i per second has a proper mo ion of eigh m les per second , is t a th e t i i t t and a s r of Sirian ype . There s a d s an companion “ ” u u t i t o in i . Reg l s , seemingly s eeped ind go , says M ss Clerke t Dis ance , Angle ,

is o I t s is 1 2 The variable ( R) of a deep red c lor . period 3 days ,

it t t o t t t u t and fades from a ﬁf h a en h magni de s ar . t th e u t t — A . 6 D . . No e do ble (35 ) Sex an is 7 . , , t a t th e t t u (6) has a dis n companion of eigh h magni de .

t t h e u 1 8 6 1—1 8 6 t a u No e neb la 3 , large and brillian , do ble n u t neb u la i powerf l elescopes . (7 ) is one of th e d o u bl es b es t observed when it is not q u ite n l t h t dark or i moonlight . The co ors of e s ars are yellow and green .

I 2

LYRA

A NGL E R E M A R K S

A do u ble do u ble . The fou r st ars are do u btless physically con d n ecte .

Topaz , gree he fou r st ars M u ltiple form th e lett er ( C

Y . A ﬁne ﬁeld in which t here is anot her dou ble

u e . Yellow , bl

t 3 one o f th e t u t u ou . No e (1 ) Cygni , mos bea if l of d bles The marks th e location of t h e famo u s ring neb u la t e- it d im t ( 5 7 In a hre inch glass has a , mis y appearance , a nd it is abo u t th e apparent diamet er of th e planet J u piter 6 1 e 2 t t u - Between ( ) and ( ) note a fain s ar . A fo r inch glass reveals tw o other st ars of th e 1 2 th and 1 3 th magnit u des re ct iv l th e d eb illis s im a s pe e known as . ” a s t nth t u 4 8 t t t o t h e Vega a e magni de companion dis an , O t u t t u right and above . N r s wor hy parallax has been fo nd for t i t t t o u it is th e his br llian s ar . According H ggins approaching t t o o I t s eart h a t h e ra e f 44 t 5 4 miles per second . proper

t o is 1 o it is t th e t . mo i n 3 miles per sec nd , and a s ar of Sirian ype

The ﬁeld abou t (6) is glorio u s for low powers . The sweeping

between Lyra and Cygn u s is exceed ingly ﬁne .

is 1 2 2 1 h rs . (5 ) a remarkable variable . Period , days ,

u . u . Maxim m , Mg Minim m , Mg In th e great Harvard refract or Vega is seen with no less t han 3 5 compa nions . 3 O 0 ﬂ Cy g m Cy gnu s Page 59 Hercu les Page 11 A q u ila Pa e 45 g ' Dra co Page 9

I S VI RGO

DI S T A NC E A NGL E R E M A R K S TUD E S

oth yellow . A beau t ifu l Ob e t j c .

A ﬁne pair .

Yellow , red .

Many n eb u lae are t o be seen in th e bowl-shaped region formed “ th e t e is by s ars (n) , ( ) , which called The Field of

‘

" th e u a u t 0 . Neb l . Use abo 4 power i u E t in t u n s u t (7 ) s a variable do ble . ach s ar r decline abo ’ t u t 1 6 t h e half a magni de , and recovers wi hin a few days . In 75 dis t ance between th e component s was In 1 8 3 6 th e t w o st ars were s o clos e together that they co u ld no t be split wit h h e t t th e th e t t . t . larges elescopes Now s ars are apar , and t is is t o in th e d ist ance between hem widening . (7 ) bes bserved

i t I ts u t is 1 8 0 . twilight or moonl gh . period of revol ion years is o f th e n t t is oa th e Spica Siria ype of s ars , and appr ching t o earth a t th e rat e of from 9 1 4 miles per second . t t h e u 2 8 it s The loca es neb la 3 7 . Webb says resemble t t t it is u t u u t t a paper ki e , and ha bea if lly gro ped wi h hree in th t tw o u a e . s ars . There are neb l e ﬁeld Th e t s v m x m a re fre s ar ( ) , ( ) . ( ) . and u t th e q u entl y occ l ed by moon .

1 6 VI RGO

D enebol a

I 7

BOOTE S

DI S T A NC E A NGL E R E M A R K S

t t Bo h whi e . u Yellow , bl e .

A b in a r P y . eriod , 2 6 1 years . Good contrast of

colors . t Yellow , whi e . t u Whi e , bl e . A beau tifu l ob ect j . t Yellow , whi e . u Yellow , bl e .

u Yellow , p rple . t Fine contras .

Orange , green . u S t A s perb igh .

’ A rct u ru s is a pproach ing t h e earth a t t h e rat e of 4 5 miles I t s t t 2 t per second . excessive remo eness (Pe ers gives 5 ligh years) e n ables u s t o recognize in it perhaps t h e most st u pendou s ” t s u n within o u r imperfect cognizance . I has a proper mot ion

2 m is t th e t a of 3 7 iles per second , a s ar of solar ype , and has o it is u dist ant companion of a pale lilac col r . In brilliance eq al o 0 0 0 u u t 5 s ns like o rs .

The component s of (f) are rapidly narrowing . In a few a n t it years only t h e most powerfu l t elescopes c spli . ” ( e) was called P u lcherrima by Smyt he on acco u nt of its

u t 1 6 0 is . extreme bea y . A power of recommended OF T HE NlVERS ITY B OOTES CAN E S VE NATI CI

DI S TA N C E A N GL E R E M A R K S

t Bo h yellow .

u Red , bl e . t t Fine con ras .

Yellow , ashy .

° t - t t is u th 7 nor h nor hwes of Cor Caroli La S perba , a 5 t u t t I t is t h e magni de s ar of brillian red color . one of seven or t t t h e t h t is t eigh naked eye s ars of 4 spec ral class , and no ed for t h e t i its ﬂ brillian color ng of ashing rays . “ Webb describes t h e cl u ster 3 6 3 6 as a brilliant and beau t ifu l ' u t n o t t 0 0 0 m a ll s t a glob lar congrega ion of less han 1 s rs . “ ”

u t u is t . t So h of La S perba a ﬁne pair of 7 h Mg s ars . The “ ” n u 2 is th e i u eb la 3 5 7 Spiral or Wh rlpool Neb la of Lord Rosse . COMA B E RE NICE S

M A O N DI S T A N C E R E M AR K S

Orange , lilac . o t t Fine c n ras .

t Whi e , lilac . u Lilac , bl e .

s t t t t t h Webb say of his cons ella ion , A ga hering of s ars whic obvio u sly requ ire distance only t o become a neb u la t o th e naked eye .

2 2 CANES V E NATICI AND COMA BE RE NICES

5 0 L a S uperba

CA NE S V E NA TI CI

4 O

COMA B E RE NICE S LIB RA

A NGL E R E M A R K S

t t Fine con ras .

t t Pret y objec .

t o il 2 1 2 6 1 t t According W son P . resembles Cygni . Bo h s ars t in t h e t have a large proper mo ion same direc ion . a t t u n - ( ) has a ﬁf h magni de companion visible i an opera glass . n t u —6 t r Mag i des 3 , colors yellow , ligh g ay . is t h e t in It is (B) only naked eye s ar green color . a wide l - ﬁe d . t u u . do ble for a glass Colors , emerald , ligh bl e

L t o L ibrm . tt A line drawn from ( ) (B) , and prolonged a li le

it s t t th e u t 0 8 in t o beyond leng h , loca es cl s er 4 3 Serpens , close

’ th t t u t t e ﬁf h magni de s ar ( 5 ) Serpen is . t S in t h t t S ars may be een e day time wi h even a small elescope . ” I t is said t hat a t elescope of I apert u re will S how st ars of th e h t it 2 d t u . F or t t o tr t e magni de hose who care y experimen , is u t t t u t o t u , s gges ed ha a planisphere be sed loca e some s ch ’ t t it is t h e n brigh landmark as Orion s bel . When on meridia t here sho u ld be litt le difﬁ cu lty in seein g th e st a rs even in broad t dayligh . L IBRA

S c i orp o Pa ge 33 Virgo Page 17 Ophiu ch u s and S erp ens Pag e 27 OPHIUCHUS

D O U B L E DI S T A N C E A NGL E R E M A R K S

Yellow , red . t t Fine con ras .

Yellow , red . Triple u Yellow , bl e . t t Fine con ras .

2 2 1 6 6 t u . Whi e , bl ish

d re . Yellow , i F ne close pair . u Yellow , bl e .

Webb says th e neighborhood of t he new st ar 1 8 4 8 S h o u ld be t wa ched . SE RPE NS tt (In do ed line . )

DI S T A NC E R E M A R K S

t t Bo h whi e . A t ﬁne objec . t Bo h yellow . Lies in rich ﬁeld .

Green , lilac . ° 2 6 u — 5 Bl e , yellow . 5 I o ” 2 2 3 4 2 2 6 1 2 0 — ” 2 1 9 3 1 6 7}1 1 3 1 72

Observe th e clu ster 4 0 8 3 close t o 5 ) 0 hiu ch i v t i i ( 7 ) Op and ( ) Serpen s are colored var ables . t In - M 6 8 . u . D A No e ( ) Herc lis g . , . , . ,

2 6

SAGITTA

R E M A R K S

u Green bl e .

in t is t The sweeping his region magnificen . a t u ( ) and (6) are bo h wide do bles . I u t t i u . t ( 5 ) commands a fine gro p A few min es nor h of , is u t u t u In a bea if l s ar , sapphire bl e color . ' ’ I n i u it 0 0 u lies a rich reg on . A circle aro nd of 3 or 4 radi s will inclu de several very pretty litt le 8t h or 9th magnit u de i pa rs . t th e u t 2 0 s It is i t t No e cl s er 4 5 . Webb say , an n eres ing ” ° u t 1 specimen of t h e process of neb u lar resol ion . Abo u t so u th of it is a beau t ifu l low power field cont aining faint pair u and triple gro ps . DE LPHINUS

DI S T A NC E A NGL E R E M A R K S

l . Golden , emera d t Fine contras .

0 u t u ( ) lies I n a bea if l ﬁeld . There is a prett y pai r in th e ﬁeld wit h ( e) a i i s t o f t u t . J u st S W . of (r) a ripl—e 7} magn de s ars 2 6 2 8 u i t 2 a . 6 6 . D . . No e Aq l e Mg , , A

2 8 SA GITTA AND DE LPHIN US

SAGITTA

Aq u ila Page 45 Cy gnu s Page 5 9 Pegas u s Pag e 61

2 9 SAGITTARIUS

DI S T A NC E A NGL E R E M A R K S

u Yellow , bl e .

This do u ble and t h e one follow ing are in S o ’ b ies k i s i Sh eld . 2 2 0 6 u . 3 Yellow , bl e A bea u tifu l O b ct je .

t u t u a in t i There are many ﬁne s ar cl s ers and neb l e h s region .

h e u t 2 t t . 2 . 2 . 2 . a ll No e especially cl s ers M , M 4 , M 5 They are v t o th e t h e S isible naked eye , and former has been known ince “ 1 6 6 t h e s o- Triﬁd u 5 . Observe called Neb la 4 3 5 5 (M . also h - 0 . 1 t e u th e 4 4 3 (M 7) known as Horse shoe Neb la , one of n ebu la t hat can be O bserved wit h comparatively low optical u S it t o u power . H ggins has hown be gaseo s .

1 8 is in u . u M . a glorio s ﬁeld A region of s rpassing splendor .

u t 1 u t A is t t u t i Abo ? so h of ( ) a ﬁne seven h magni de r angle . It is seldom t hat more t han 2 0 0 0 st ars are visible t ogether

t h e u t o t h e 6 t h t u t o naked eye p magni de . Using a t ele scope of only 2 5 -inch apert u re Argela nder regis t ere d t t o t h e t u s ars down 9 % magni de . When t h e phot ographic chart ing of t h e sky is accomplished t t t i a bo u s ars will be iden iﬁed and ndexed . t o t h e t t u t h e t is t o According Newcomb , o al n mber of s ars be ‘ t u co u n ed by h ndreds of millions .

3 0 Ca pricornu s Page 5 1 S corpio Pa ge 33 Aq u ila Pa ge 45 SCORPIO

D O U B L E DI S TA NC E R E M A R K S

h t u W i e , bl ish . t t Fine con ras .

W t u hi e , bl e . t Whi e , gray . u t Bea ifu l ﬁeld . tt A pre y pair .

The cl uster 4 2 6 4 in Ophiu ch u s was discovered by Messier in t it 1 6 u u . 1 8 e 7 4 , and ca alog ed as a neb la In 7 4 H rschel proved t o u u t u t 2 6 8 w a s be a glob lar cl s er . The cl s er 4 discovered by ’ I t is 2 in t . Herschel . diame er 2 0 is a o u u t t o t 4 7 gl b lar cl s er , fairly brillian , foll wed by a fain u neb la . ( v) Scorpii is s aid t o be th e most beau tifu l qu adru ple gro u p in t h e s heaven .

“ t u 0 th e t Herschel ho ght that the clu s ter 4 1 73 ( 8 M . ) was riches t in th t h e t t u t e . mass of s ars heavens On eas ern side of his , cl s er “ ” “ is t t t o th e s o- a s arless spo , a black hole , similar called coal

in u it t o a t sack Cygn s . Webb likens come .

t o th e 1 t u t t An ares has a c mpanion of 7} magni de , dis an ’ t s t angle green in color . Proc or say a larger glass han a - fo u r inch is req u ired t o split it . — tt s u t is u 2 1 . t u s 8 A li le o h of (E) a do ble, 9 99 Magni de , 7% , ° t 1 0 dis ance , angle , 3 t u (6) may be an op ical do ble .

3 2 SCORPIO

P Oph i uch i O

A nta res

Ophiu ch us Page 27 Libra Page 25 S agittarius Pa ge 31 3 3 URSA MAJOR,

DI S T A NC E A NGL E R E M AR K S

t t Bo h whi e . Alcor in th e same ﬁeld . Fine cont rast of

colors .

Pret ti ly gro u p

ed .

t u Whi e , bl e .

Not e th e tw o ﬁne neb u lae separated by only half a degree ,

0 1 9 4 9 and 1 9 5 . is t u a 2 3 4 3 (M . 9 7) a large plane ary neb l called The Owl u u t t h e s o- u i Neb la . So h of called Spiral Neb la n Canes i is t h e u t u ou l Ven a t ic . , bea if l and easy d b e Cor Caroli

‘ is rob ab l t h e t u t in th e (f) p y bes known do ble s ar heavens , t h t u t u I t is t o and is one of e mos bea if l . easy ﬁnd and is most

o V in t I t w a i effective t iew a small elescope . s d scovered by

Riccioli . n 7 ) lies i a ﬁne ﬁeld . Th e t 3 e t th s ars (1) ( ) , and (n) are all s ars of e Sirian

a i t t h e t s . t ype . ( ) a s ar of solar ype

o - t i in i m (i) and ( ) are spec roscop c b ar es . The for er was th e t ﬁrst do u ble pho ographed by Bond . t i t is in th e t D ° A . . 1 1 A h rd s ar ﬁeld wi h , , 3

3 4

URSA MINOR

DI S T A NC E R E M A R K S

Yellowis h -w h i t e u and bl e .

Both yellow .

u A ﬁne do ble .

0 If yo u r glass is a good one and t h e atmospheric conditions are o u u t u in t h e favorable , y sho ld have no ro ble seeing companion o t t t t it is t t u t Polaris . Webb s a es ha easy wi h any hing m ch 2 it is fﬁ u t t o t r t h e t exceeding inches . If di c l see , y me hod of

t a t i t t t t h e . inver ed vision , or gazing a d s an par of ﬁeld This met hod brings int o u s e a more sensitive part of t h e ret ina and u often s cceeds admirably . t t t t h a s Polaris ligh years dis an (Pe ers gives 3 years) , a

2 7 iS a xo a ch in th e proper m of } miles per second , and /é g t a t t h e t 1 6 It is t t h e ear h ra e of miles per second . a s ar of Solar At th e t o u r s u n u r t t ype . dis ance of Polaris wo ld appea wi h an

- t u t is t h e S opera glass as a 75 magni de s ar . Polaris one of pec i t ro s co c . I ts is Th e t 0 1 p binaries period days . s ar ( 4 , 4 ) is it s t u t it t o Draconis given here , as si a ion renders easy observe t h e t o is t when elesc pe direc ed t owards Ursa Minor . URS A MINOR

5 0 Dra conis

O 0 K Dra coms .

Urs a Maj or Page 35 Dra co Page 9 Ceph eu s Page 55

3 7

T H E C O NS T E L L A T I O NS O F A UT U MN

3 9 ANDROME DA AND TRIANGULUM AND R O M E D A

A NGL E R E M A R K S

u . Yellow , bl e e u t i V bea fu l .

u . Yel ow , bl e

u . Yellow , bl e —S 7%— % 4 1 1

The indicat es t h elocation of t h e great neb u la which can t t h e th e be readily seen wi h naked eye , and only one which was ' in -tel eS CO ic t m es I t s discovered pre p . place was marked on a st ar map brou ght from H O land believed t o dat e from th e 1 0th t u It is th e t t u ti u l cen ry . known as ranscenden ly bea f ” t t n qu een of t h e neb u la . I is a disappoin ing object i an o t e rdinary elescop . u 1 8 8 in th e t th e A . s t u In g , 5 , a new ar shone p very mids of h t t u It t o t u t e . gre a neb la . faded invisibili y d ring nex year The dist ance of th e neb u la from t h e eart h is s o great as t o render abortive all att empt s t o measu re it wit h t h e most p owerfu l t t It s u t ins ru men s . dimensions do b less are inconceivably enor t u o t t h e t . mo s , and bey nd comparison wi h hose of Solar Sys em t in h It (7 ) is one of h e most beau tifu l dou bles t e heavens . t t c in 8 8 t t was ﬁrs no i ed by Mayer 1 7 . The con ras of colors is very ﬁne . T R I A N G ULUM

R E M A R K S

u Yellow , bl e . An

exq u isit e pair .

' t I t is 0 in x t t . Note h e neb u la 3 5 2 discovered by Messier . e en t a t t o is co v ered The ﬁrs s eroid be discovered , Ceres , was In u u in 1 8 0 1 Triang l m . is t (7 ) a ﬁne naked eye riple . 4 0 Gt .

Aries Page 47 Pers eu s Page 63 P egas u s Page 61 Cetu s Page 57 4 1 AQUARI US

DI S T A NC E A N GLE R E M A R K S

t Bo h green . Fine

pair . Period 0 75 years .

u Yellow , bl e . t t Whi e , garne . u Yellow , bl e . t t Fine con ras .

t Fine contras .

th u 1 A u a rn t u For e do ble 0 7 q see Ce s . th e u 6 8 u t u u u c Look for neb la 4 7 , a bea if l ro nd neb la dis overed l i t - Ma ra d in 1 S in t . by 76 4 . A ﬁne igh a hree inch glass

t t v t u 6 2 8 u is . J s wes of ( ) a ﬁne specimen of a plane ary neb la , 4

I t w a s c in 1 8 2 it th dis overed by Herschel 7 . Rosse calls e

t u u I t is t t h e s u n a t th e t 1 Sa rn neb la . moving oward ra e of 7

' F u t t i s 2 miles per second . ive degrees n orth and j s eas of (B) “

M . t u a it t t o u t , a large brigh neb l ; from s reams of s ars branch , t t h e t t t 1 6 2 is th e aking direc ion of angen s , 4 years given for ° u t t u t 6 is 2 u period of Abo 4 eas by so h of ( ) 9 , a ﬁne do ble .

4 2

AQUILA

DI S T A NC E A NGL E R E M A R K S

Yellow , green . u Fine do ble . t Whi e , lilac . t u Whi e , bl ish .

Optical dou ble . Primary bl u ish t whi e .

u . Yellow , p rple

t is 1 6 t t t t Al air ligh years dis an , has a proper mo ion of 9 s is t h e t a t th e t miles per second , and approaching ear h ra e of I t is t th e t 2 . 7 miles per second a s ar of solar ype , and has a t t t u t en h magni de companion . Dis ance , Angle , is At u it s R . a variable of a deep red color . maxim m magni

i A t t i 1 t u s u 1 1 I s s . de minim m , . period 3 5 days

7 is t u u . t u . ( 1) a variable wi h maxim m 3 1, minim m 4 7 magni de

t s is u I . period 7 days , 4 ho rs Stru ve gave white as t h e color of both of th e stars in u t u O t t O f t Not e t h e cl u ster 4 4 4 0 . A bea if l bjec consis ing s ars o of th e nint h t th e twelfth magnit u des .

4 4 Alta ir

Cy gnu s Page 5 9 Page 15 Ophiu ch u s Page 27 Ca pricor nu s Pa ge 5 1 D elph inu s Pa ge 29 ARI E S

DI S TA N C E A NGL E R E M A R K S

t Whi e , yellow Disagreement as t o colors . t Whi e , lilac .

t u . Whi e , bl e , lilac

Bot h white . A beau tifu l d ou

ble .

s . —— Topaz , apphire 5 8 1 1

a is 0 t t t t t ( ) 4 ligh years dis an , and has a proper mo ion of eigh

I t is t t h e t . miles per second . a s ar of solar ype I t is o (7 ) was th e ﬁrst do u ble discovered . was d c vered by

in 1 6 6 t Hooke 4 , when he was following a come . Tau ru s Page 67 Pis ces Page 65 Cetu s Pag e 5 7 A n dr om ed a Pa ge 41

4 7 AURIGA

DI S TA N C E R E M A R K S

t Greenish , whi e . —8—1 1 u 5 Yellow , bl e . —— 1 1 o u 5 75 Yell w , bl e .

t t Whi e , viole .

Yellow , lilac . t Whi e , ash .

u Yellow , bl ish . u t u Bea if l .

u In Perse s . u In Perse s .

t th e u t 1 1 1 u t Smy he describes cl s er 9 as an obliq e cross , wi h t in u u in t h e a pair of large s ars each arm , and a conspic o s one c t th e t t th e t en re , whole followed by a brigh s ar of seven h t u u tt t magni de . There are several wide do bles sca ered hro u gh is u t u th it and th e whole region very bea if l . Of e clu ster 1 2 9 5 “ E in t u t it is t u t Webb says , ven small ins r men s ex remely bea i ” t is l th e t i s . fu . One of ﬁnes of class Capella probably 3 0 t t 0 t t t . t u 1 1 . I t ligh years dis an Pe ers gives 7 ligh years , S r ve

t 1 1 is has a proper mo ion of miles per second , and receding

t h t a t t h e t 1 2 t is from e ear h ra e of 7 or 3 miles per second . I a model star of th e solar type . t is u t it t u The ligh of (f) sing larly in ense for s magni de .

4 8 AURIGA

2 681 o Cap ella

Pers eu s Page 63 Tau ru s Page 67 Gemini Page 75

4 9 CAPRICORNUS

DI S T A NC E A N GL E R E MA R K S

A naked eye d o u t ble , and ele scopic do u ble

dou ble .

Bot h yellow .

u . Gold , bl e t u Whi e , bl ish . tt A pre y pair . u Orange , bl e .

u Yellow , p rple . t s t Fine con ra .

t th e t u t 0 I t tt t No e s ar cl s er 3 M . lies a li le nor h of a “ t t u t s it t fif h magni de s ar . Webb describe as modera ely t u t u t t t t t u t brigh , bea if lly con ras ed wi h an eigh h magni de s ar ” u t 0 it . beside Use a power of abo 7 . 7r 0 tt t t t t t u ( ) , (p) , and ( ) form a pre y li le riangle of fif h magni de s t ars . t n th e t a In a good glass five s ars shou ld be seen i field wi h ( ) .

CASSIOPE IA

A NGL E R E M A R K S

t u Whi e , p rple . u Green , bl e . Coloring t in ense .

o u G ld , bl e . Remarkable

colors . u Yellow , bl e .

Orange , green .

x t lie in - t (7 ) and ( ) bo h very rich fields . Half way be ween t t u t t in t h e th e tt hem , no e a fine cl s er somewha shape of le er “ ” t r o is u W . Be ween ( ) and ( ) a glorio s field . 7 in 1 I t is a r t ( 7) was discovered by Herschel 779 . bina y wi h ob erck 2 2 - u t o D 2 . B a period , according , of 5 years ner gives t u t h e t 2 2 t 1 76 years . S r ve gives dis ance as ligh years . 0 O h iu ch i S t t u t t h e and 7 p are imilar sys ems , bo h have abo same t t t th e proper mo ions and parallax , and iden ical spec ra of solar t 7 3 1 e . 01 is t t t t o tw o 8) 4 7 ligh years dis an , and has a proper mo i n of h e t I t is t t . miles per second . a s ar of solar ype is 2 0 t s t t t t t en (B) ligh year dis an , wi h a proper mo ion of miles per S econd . t o th e th t is u t . (7 ) a gaseo s s ar , and belongs 5 spec ral class ’ t h e t ch o s t t h e u The marks posi ion of Ty s ar , famo s vari 1 2 able of 5 7 . t th u t 2 2 6 tt con No e especially e cl s e—rs 3 9 and 5 . The la er t s ou t u 8 . ain a d ble , magni des 9

5 2 “ CAS SIOPE IA

163 °

Ceph eu s Page 55 And romed a Pa g e 41 P ers eu s Page 63 P egas u s Page 61

53 CE PH E U S

D I S T A N C E A NGL E R E M A R K S

t Yellow , whi e . Greenish whit e u t bl ish whi e . S A plendid pair .

t u Whi e , bl e .

t t th e s o- t t th e t t in t he No e (i ) , called garne s ar , reddes s ar t nor hern hemisphere . Many small me teor showers radiate from Cephe u s d u ring t t t u th e middle and la er par of J ne .

u 2 0 a is it is t The do ble 3 5 3 Cassiopei given here , as convenien ly t t o t h e t u t is u s loca ed observe while s den exploring Cephe . — tu 6 . t u . Magni des , 7 Dis ance , Angle , Yellow , bl e (6) is a beau tifu l do u ble and h a s been likened t o th e celebrated

(6) Cygni .

5 4 CE PHE US

Cas s iopeia Page 53 Cy gnu s Pa ge 5 9 Dra co Pa ge 9 Urs a Minor Pa ge 37

5 5 CE TUS

R E M A R K S

Topaz , lilac .

u Yellow , bl e . A bea u tifu l d o u

ble .

u Yellow , bl e . u Yellow , bl ish .

u A ﬁne do ble .

Coloring ﬁne . Aq u a rn

A wide do u ble . Not e a bl u e 5 %

Mg . star in t h e

ﬁeld .

1 t t u t t (x) has a seven h magni de companion dis an 3 .

t th e u 1 8 in 1 8 No e neb la 3 discovered by Caroline Herschel 7 3 . l i t I t is . described as being ong , narrow , and br gh n t u I t t The famo u s variable Mira is i Ce s . was ﬁrs observed u in 1 6 I t t h e as a variable by Fabrici s 5 9 . varies from second I ts 1 t t u . s t o th e nin h magni de period averages 3 3 day . Mira ‘ t a is a red st ar with banded spec r . CE TUS

Pis ciu m

-0 2 15o

Pis ces Page 65 Ta u ru s Pa ge 67 A q u arius Page 43 A ries Page 47 E rida nus Page 73 S7 CYGNUS

DI S TA NC E R E M A R K S

b l iI e Yellow , .

Very ﬁne . u Yellow , bl e . t t Good con ras . u Red , bl e . u Orange , bl e . t t Good con ras . A do u ble d o u

ble . t l Whi e , li ac . 6 light years d is t t t an . Neares t o eart h in t h e nort hern hemi

sphere . ” 2 0 u u t A q adr ple s ar . ” 2 0 8 ll 0 2 ” ° 1 6 37 36 ° 2 6 1 6 u 4 Yellow , bl e . ’ ° 4 8 I 78 I 74 ” ° 2 2 4 8 6 1 0 2 2 4 ” ° 2 2 5 78 1 5 1 2 7 1 6 ” ° x 2 73 In ﬁne ﬁeld . ” ° 3 5 4 5

O bserve with a low power t h e wonderfu l st ar stream abo u t - locat es th e celebrat ed D u mb bell neb u la in Vu lpec u la

(M . Use a low power . ( a ) or Deneb is approaching th e eart h a t th e rate of 3 6 miles t o ew com b it t u e per second . According N will even ally b come so near a neighbor as t o o u tshine d u ring several thou sand years every visible star . Between ( a ) and (e) is t h e dark ri ft in t h e Milky Way called “ ” t h e coal sack . — 6 n 1 8 8 3 3 0 separate phot ographs were t aken of ( I ) i 6 7 . These u t fu rnished material for meas remen s . 5 8

PE GASU S

A NGL E R E M A R K S — 2 7 8 t 3 Yellow , viole . — Coloring ﬁne . 4 1—8 1 6 71 6 4—8 7- 71

8 8 is tt in th e t M . D . There a pre y pair ﬁeld wi h g , , , o

A ' s 3 4 9 Ma ra ld i n i 1 . The clu ster 1 5 M . was discovered by 74 5 is u t u S t u t t h e (B) a variable and shows a bea if l pec r m , wi h 1 1 1 dark bands of Class . t u u t 0 t h e t . Wi hin sq are , Argelander co n ed 3 naked eye s ars 2 —8 A . 8 t t 2 8 t a M 6 D . a No e 94 Lacer , g , , , , also Lacer , t a beau t ifu l q u adru ple s ar . - ° ii 1 1r 2 t t s ( ) and ( ) form a grand pair . Nor h of hem 2 i a ﬁne 2 8 —8 A . u 2 0 M D . do ble , 9 5 ; g , 5 53 , , 6 t iz th e t v . " ( ) exhibi s a phenomenon no iced by Herschel , pendu lu m-like os cillation of a small st ar in th e same vertical t h t i u t o t r e s s . wi h a la ge one , when elescope sw ng from side ide ” 1 h t 6 2 t t e 1 h M . 1 (7 ) and ( 7) have fain companions of 1 g . , D " t and 9 0 respec ively . E QUULE US

R E M A R K S

‘ t u Whi e , bl e .

A ﬁne pair . t Yellow , whi e .

6 t d 2 A . t h e t t ni u e D . has a companion of en h ma , , , and ’ ' t Friend l is remarkable for th e fact (I q u o t e rom Mrs . Mar in s y S ta rs t t it is u t o O ) ha s pposed have a period of nly 5 years , t h e shortest y et discovered for a vis u al binary . 60 PE GAS US AND E QUUL E US

meda e

PE GAS US PE RSE US

DI S T A NC E A N GL E R E M A R K S

t u Whi e , bl e . Several faint stars near it

u t u t A q in ple s ar . o Yell wish , lilac . t Both whi e .

u Yellow , bl e .

a is t t t t ( ) 4 4 ligh years dis an , and has a proper mo ion of one I t is t h e t a t th e t mile per second . approaching ear h ra e of 7 miles per second . Algol is approaching th e eart h a t th e rat e of tw o miles per t i t th i t bi t I s e . second . a s ar of S rian ype The varia li y of u t n t t I t s Algol was do b less discovered i very ancien imes .

8 1 m . is 2 2 0 . . u 2 . period days , hrs , 4 m D ring hrs , 4 , Algol

of th e t u th e 6 . appears second magni de , remaining % hrs are u u th e t t o th e u t t u occ pied by a grad al decline of s ar fo r h magni de , t t u and it s eq u ally grad u al ret u rn t o h e second magni de . The variabilit y is cau sed by t h e periodic eclipse of Algol by a dark

i t is t e . companion , whose d s ance from Algol hree million mil s The cl u sters 5 1 2 ' and 5 2 1 are considered t h e finest in t h e a he vens . The clu ster 5 8 4 has a diamet er of Over 1 0 0 st ars ca n be co u nted in it . Very fine low power field .

6 2 2 9 A nd romedae

Algol

{it 717

A nd romeda Pa ge 41 Au riga Page 49 Cas s iop eia Pa ge 53 6 3 PISCE S

R E M A R K S

u Green , bl e . A u l ﬁne do b e . The movement of t h e com pa n ion is very slow . u t u t A bea if l sigh . No change noted in 1 0 3 years . b u Yellow , l e . Two bea u tifu l t s ars .

t u Whi e , bl e . N o t change no ed . t u Whi e , p rple . tt Pre y pair .

t . Yellow , whi e

Topaz , emerald .

t t t u t s (p) and bo h ﬁf h magni de s ar , form a splendid pair .

1c i in ( ) s a ﬁne ﬁeld .

h u 0 a u t t t t e . re s it No e neb la 3 7 There fo r fain s ar near . t is ou in t t th (7 ) Arie is a ﬁne d ble his par of e heavens . S ee

Aries . i t (s) s a spec roscopic binary .

‘ t t h e t 6 s t Viewed wi h Lick refrac or of 3 inches , any given ar is t t t 2 - t imes brigh er han when shown by a inch elescope . v is u t u t th e ( ) freq en ly occ l ed by moon .

6 . 4 PIS CES

Aries Page 47 Page 5 7 Pegas u s Page 61 And rom ed a Page 41

6 5 TAURUS

DI S TA N C E R E M A R K S

—- 6 9 9 2

E u . merald , p rple u Red , bl e .

t u A beau if l pair . t u Whi e , bl e .

01 02 a n h as a ( ) and ( ) are aked eye pair . a n ked eye companion .

t o A . t t u o a D . Aldebaran has a en h magni de c mp ni n , , , is t t t u t It is 2 8 ht s 3 and a s andard ﬁrs magni de s ar . lig year t t t u is dis an , has a proper mo ion of fo r miles per second , and t h e t a t th t 0 It receding from ear h e ra e of 3 miles per second . t t h e t has a spec ru m of solar ype . th e u th e s is a u a u s t Alcyone l cida of Pleiade , q dr ple ar and u t u t a very bea if l objec . t The Pleiades are probably 2 5 0 light years distan . They t t u t h e have a common proper mo ion , and a spec r m of Sirian

t t 2 0 0 0 t . t ype . A pho ographic pla e of t hem shows over s ars ” t t e t u th e t The loca es h celebra ed Crab Neb la , ﬁrs u o ot th e ou t neb la disc vered by Messier . N e ﬁeld ab 6 6

E L L ’ AT IO NS O F W I NT E R CANIS MAJOR

D S A E A E R E A R S I T NC , NGL M K

u t 1 is u u t o th e The cl s er 4 5 4 a s perb gro p visible naked eye . .

' a t in it s c t Look for red s ar en re . u o o t I t is t is u b u t t o u r . Siri s a do ble , close for elescope eigh t t t t ligh years dis an , and has a proper mo ion of nine miles

t o u it is th e per second . According H ggins receding from t a t th e t t t o t t -tw o ear h ra e of eigh een wen y miles per second . - u s is th e t t Vogel raises t his t o fort y s ix miles . Siri brigh es t t o f th e t t t 1 ud represen a ive grea spec roscopic ype , which incl es t th e t et t u t s u n more han half of all s ars y s died . This brillian is s u pposed t o be su rrou nded by an enormou s atmosphere of i 6 t o u r s u n I t s t . hydrogen . 3 imes as brigh as O u r s u n wou ld appear as a t hird magnit u de st ar if a s distant t from t h e ear h as is Siriu s . Not e t h e neb u la 1 5 1 1 and th e cu rving row of faint st ars near CANIS MA"OR

S iriu s

Monoceros Page 79 Lepu s Page 77 Orion Page 81 E RIDANUS

DI S T A NC E A NGL E R E M A R K S

u Topaz , bl ish . t t Fine con ras . Discovered by 1 8 1 Herschel , 7 .

u Gold , bl e .

h t Yellow , w i e .

Discovered 8 c 1 . Hers hel , 7 3

t t 8 Note h e plane ary neb u la 2 6 . Lalande described it as th e t t t t h e mos ex raordinary objec of kind he had ever seen . E RIDANUS

Orion Page 81 Lep u s Page 77 GE MINI

R E M A R K S

t Bo h yellow . A beau tifu l Ob ect j . u Yellow , bl e . t u Whi e , bl e . u Yellow , bl e . t t Fine con ras . u Yellow , p rple .

u Greenish , bl e . e u t u V ry bea if l .

( 1r) and (a) b oth h ave eleventh magnit u de companions ” ” t t 2 2 t dis an and 73 respec ively . t s n a it (7 ) has a remarkable array of s ar e r . Castor is Considered th e ﬁnest specimen of a binary in th e t h t s t o u t nor hern emisphere . The s ar make a comple e rev l ion t w a t t t o in abo u t 1 0 0 0 years . Cas or s h e ﬁrst s ar shown be t of a r a t It h a s t u of th e cer ainly bina y char c er . a spec r m t Sirian ype .

The cl u ster 1 3 6 0 is one of th e ﬁnest clu sters in th e heavens . A marvello u sly striking object No one can see it for th e ﬁrst t t u t t ime wi ho an exclama ion . u is 8 t t t h a s a t 2 Poll x 4 ligh years dis an , proper mo ion of 7 is t h e t a t t h e t miles per second , and approaching ear h ra e of

I t is b u t t s t . 3 3 miles per second . a coarse ﬁne riple ar u t 2 is The region abo ( 7) very rich .

LE PUS

DI S TA NC E R E M A R K S

t Yellow , garne . u —— Yellow , bl e . 6 9 8 %

’ —— u t 6 a is 8 0 a u t t a —8 8 s . Abo from ( ) . H . 3 7 , m l iple r , Mg 7 9 1, u t u u t t o a bea if l cl s er for small elesc pes . ’ t t t t it s R . A No e , a celebra ed variable , Hind s crimson s ar . u it is t in s it a s minim m in ensely red color . Hind describe t As resembling a bloo d drop on t h e backgro u nd of h e sky . regards depth of color no other s tar visible in t hese latit u des

o t t s is u t 6 s . At can be c mpared with i . I period abo 43 day

u its t u is 6 t o a t u 8 . maxim m magni de 7, minim m “ I ts spectru m indicates t hat it is smothered with absorbing s u n t t a t t vapors , a near ex inc ion , which in ervals experiences an accession of energy and b u rst s t hro u gh it s stiﬂing envelope with ”

t o t S . explosive radiance , only fain and ink once more “ th e u t 1 1 1 2 u u t d is Observe cl s er , A splendid glob lar cl s er covered by Mechain which Messier described a s a st arless th e t t o neb u la with a brilliant centre . . Herschel was ﬁrs resolve t u t t I t t t t t his neb la in o s ars . appears from pho ographs aken ha

ﬁve stars o u t of t h e tw o hu ndred of t his cl u ster are variable . LEPUS

1112

O H 375 2 Orion Pa ge 81 a nis Maj or a e 71 C P g ’ E rid a nu s Pa ge 73

77 MONOCE ROS

DI S T A N C E A NGL E R E M A R K S

One of th e ﬁnest sights of t h e s —— heaven . 6 1 0 1 1

n u Golde , bl e .

u Yellow bl e .

t th e u t 1 2 t o th e No e cl s er 4 4 , visible naked eye , and very

u t u 1 6 t t s bea if l . Also 3 7, fairly large and crowded wi h s ar of

th e t t u u tt u . nin h magni de , incl ding a pre y do ble There is a glorio u s low power ﬁeld abou t Obs erve th e ﬁne orange color of

1 1 n 1 8 1 ( ) was discovered i 7 . Procy on

Orion Page 81 Canis Maj or Pa ge 71 Gemini Page 75 79 O RION

DI S TA NC E A NGL E R E M A R K S

— 2 6—1 0

A splendid pair . t Green , whi e .

Fine coloring . A t hird star in

ﬁeld . A beau tifu l Ob ect j . E t t t xcellen es .

2 2 \I' t t u 7 5 and have eleven h magni de companions . or is u t u u t t is e ( ) a bea if l m l iple s ar, and a colored variable . ( ) and (B) are receding from t h e earth a t t h e rat e of 3 5 and 3 9 miles per second respectively ; ( a ) a t t h e rat e of 2 8 miles per second . Proct or says a t hree inch glass shou ld S how th e nint h magni o t i t u t o A . de companion Rigel . D . , Smy h cla ms it is t t ou a es for a f r inch glass . t o t h e u 1 I t s Words fail describe great neb la 1 79 . glories u t t o t t S m s be seen be apprecia ed . A hree inch glass will how t t u h e fo u r st ars forming th e t rapeziu m in h e neb la . The whole u t th e u is in u t i u t region abo neb la rich do bles , r ples , and m l iple t u u ff t t s ars . The neb la has been nder e ec ive observa ion for 2 t is t h e t u u t t O t 4 4 years . I mos conspic o s and in eres ing bjec t I t is t h e of i s kind in t h e nort hern heavens . receding from ’ t a t t h e t 1 1 13 u t th e u ear h ra e of miles per second , which abo s n s comp u t ed velocit y t hro u gh space in t h e opposit e direction . th u s a t t Hence e neb la i probably res .

8 0 1301

B eteig eu ze

B el l atrix

2 750 1184

0+ 1179

Erida nu s Page 73 emi G ni Page 75 Ta u rus Page 67

THE DI AGRAMS O F TH E MOON

HE SE are s ket che s from a s erie s o f ﬁne ph ot ograph s ’

t . S erv i s t hat recently appeared in Mr . Garre t P s s

o h oon o excellent b o k entitled T e M . They are nly in tended t o guide t h e s tudent in th e ident iﬁcat ion of th e

o s s t - t s o lunar w nder vi ible in a hree inch ele c pe , and make

o or o s no claim t exactnes s pict rial re emblance . The mean dist ance of t h e m oon from t h e eart h is

s It s t is 2 1 6 s it is mile . diame er 3 mile , and a

th e o t t of o t little larger t han c n inen S u h America . Be

’ s of the oo s o t o t t o t h e t cau e m n c mpara ive pr ximi y ear h , it is th e eas ie st and m ost int ere st ing of t el es c0pic ob

h o n o f o ect s s t o t e s t s . j , e pecially w er a mall ele c pe A t ele s cope which magniﬁe s only one hundred t ime s ’ will S how a s pot on th e moon s s urface wh os e diameter

' i 1 2 2 o s 3 yards . One which magniﬁe s a t h u s and t ime s will enable u s t o perceive object s on her s urface wh os e

s o s o 1 2 2 s o s not dimen i n are nly yard , which d e much

t h e s Of t h e C t o a s o exceed ize api l t Wa hingt n . The

st o et t o th e oo o of s ix highe p wer y applied m n , a p wer t o s s t o t st of o t h u and , bring her an apparen di ance f r y s mile . No Object t hat c ould wit h th e slight e s t appearance o f 8 5 The Moo n

probability be a s cribed t o t h e lab ors o f intelligent crea

’ t s h a s t t on th e oo s s ure ever been de ec ed m n urface . We kn ow more of th e phys ical format ion of th e face

o f t h e oo t t o u s t o o f t m n urned ward , han we kn w cer ain

t s o f s o t t h e t o of par A ia , S u h America , and in eri r Africa . M ore t han ﬁve hundred feature s of t h e lunar s urface

s t ot os s s a have received name . Wa er cann p ibly exi t s a

’ on th e oo for t h e t t o f t h e oo liquid m n , empera ure m n s s urface during th e long lunar night I s probably n ot far from 4 60 degree s below t h e zero mark on a Fahrenheit

t o herm meter .

t of t lie oo s t h e t of The ligh full m n , which equal ligh

s t s o f o t is on e-6 1 8 0 0 0 t h t o f ar zer magni ude , , par

’ t h e s s t o t t t s th e t of t h e un ligh , and ab u welve ime ligh

oo oo ﬂ t s o t one-t t o f t h e h alf m n . The m n re ec ab u en h

l s on it o h e s u n th e o b ight which fall fr m t . In wh le eav en s t h e s t ars give ab out one-eightiet h a s much light a s t h e full moon ; The eart h reﬂect s t o th e m oon ab out fourt een t ime s a s much light a s t h e m oon s end s t o th e

e arth . I t is st t o o s th e oo t l ow o be b erve m n wi h a p wer , and

u th e o t o s of s s s s t nder varying c ndi i n unri e and un e , “ th e o s o t s o f t h e t o which , like c rre p nding ime ear h , ab und ” ff s w it h grand and beaut iful e ect s of light and hade .

’ The be s t View of an object on th e m oon s s urface is t o

it is on t h e t t o a s t h e o be had when ermina r , b undary line between t h e illuminat ed and th e unilluminat ed p ort ion s

os o t s on t h e o f t h e moon is called . Th e bjec which are

The Moo n

The n omenclature of th e moon is intere st ing becau s e it s erve s t o immo rt alize t h e name s of many of t h e wis e men of old whos e memory would ot herwis e s ink int o o f o . st o o o o o o n w h o blivi n The a r n mer Ricci li B l g a , pub lis h ed t of t he oo 1 6 0 is s o s for os a char m n in 5 , re p n ible m t ’ of th e name s of th e int ere st ing feat ure s of the moon s s f o s o o t . urface , and many hem are fanciful bey nd rea n The fact t hat s eem s t o Impre s s most pers ons w h o view t h e moon for th e ﬁrst t ime through a t ele s cope is th e

t t i s s s ou of h e of s o rapidi y wi h which t pa e t t ﬁeld vi i n . ’ The high magniﬁcat ion emphas ize s th e eart h s mot ion t o s uch an ext ent and th e s peed Wit h which we are t rav is t s st s st rt t t elling hu made manife in uch a a ling way , ha

t o t s s t s t o s t . few gaze wi h u expre ing heir a ni hmen Then , t oo t h e t o t ou t l ow o is , de ail br ugh by even a p wer a

t of o I t s s os t t t mat er w nder . eem alm incredible ha in a s mall t ele s cope crat ers on th e moon only s ix mile s in

s s diameter can be een di tinctly . Only a p ort ion of what appears on t he earlier diagram s is t th e s s s s a s t t t o repea ed in ucce ive view , heir repe i i n would t end t o ﬁll up t h e diagram with name s leading t o

co s o . t o t s t s s nfu i n In each diagram heref re , par icular re ’ is laid on th e addit ional feature s of th e moon s s urface h -a d v an cin s s t hat t e ever g unlight reveal . The word crat er is u s ed in connection wit h th e great

s s o s s o o t s t t ringed depre i n , urr unded by m un ain , ha are ’ S oo It is s o a s O numerou s on th e m n s s urface . a mi n mer applied t o the s e formation s which are t otally unlike t er The Moo n

f rest rial t s . o o t t o o o cra er N d ub hey are v lcani c rigin , o ot n o h e bu t here th e anal gy ceas e s . N hi g n t eart h is s is s t h e st f r like t hem . Ringed plain perhap be name o i i t a s t s s t s . hem , de crip ive in a mea ure They are like

t t t s s o t s 1 0 0 s t grea amphi hea re , me ime mile in diame er , s urrounded by gigantic m ount ain walls t hat ris e almost

t t o s s of t o t o t abrup ly h u and fee high . They f en c n ain a - i c t o t or o t . en ral m un ain , a b wl like p

s is o s o s s It is The lunar land cape all n a t upend u cale . s aid t hat t here are twenty-eight peaks on t h e moon t hat

ou r os o t o t s E exceed in height m t l f y m un ain . verywhere

’ on th e moon s s urface are t race s of cat aclys mic action

is os o ou r o o that alm t bey nd c mprehens i n .

o s o t h e s of the oo s t it s In c nclu i n , diagram m n repre en

t s o c or t s o t t th e o t ele c pi inver ed appearance , ha n r h

o t is at th e ott o th e s o t at t h e t o th e st p in b m , u h p, ea t o th e t th e st t o th e t s of th e s righ , we lef ide diagram

s re pectively . — MOON PLATE I

o t t h e u t h e s u n The narr w crescen of moon ill mined by , as S in th e O t t t o t t t t o hown pposi e pla e , presen s few bjec s of in eres th e O bu t s u t t u t bserver , as each ccessive nigh of observa ion n il th e o is u t new . t t tt t o it m on f ll presen s ma erial wor hy of a en i n , is Well for the st u dent t o master t h e det ails as they are pre sented . u th e s or Conﬂ t s it is The Mare Crisi m , or Sea of Crise ic , as is t h e t t t a t t t called , mos prominen objec visible his ime , and u its h u e th e t o is t I t beca se of dark analogy a sea s riking . meas u s 0 o t t o u t 2 8 0 o t t o re 3 5 miles from n r h so h , miles fr m eas t u ft u t t ou t t t h t . . e wes No e Cape Agar m , high , j ing in o th e u t t tw o t on th e u sea on so hwes , and small cra ers s rface of ’ t h e s ﬂ o a tt t its t s ou t is ea s or li le eas of cen re . The hern one

th e t . named Picard , nor hern Pierce t t h e u is t h e t Cl e m ed It is Nor h of Mare Crisi m cra er o es . i it s is t 8 0 miles n diameter . One peak on wall fee high and it cont ains a central mou nt ain divided by t hree clefts . s s t n On it eastern wall i a very deep cra er amed Tralles . th e t i t o t u nt If a mospher c condi ions are fav rable , a cer ain amo i h e r of det ail can be seen on t h e dark or ea rthl t portion of t moo i . t t i t u an d t h e t t a The brillian cra er Ar s arch s , darkes cra er, Grim ldi ,

t h e t of th e o n s n . on eas ern limb m on , have bee ee

— MOON PLATE II

Peta v iu s is one of h e t t t t ﬁnes objec s on h e moon . I t measu res 1 0 0 t o u I ts i miles from north so th . wall s divided by many ’ s t t its t s s ou t valley , while in he cen re of vas plain ri e a m n ain

6 0 0 t . t t t t is ou t 5 fee high A s raigh line radia es from h m n ain , t h f h e n u t s t t o t e o t t . ex ending so hea wall cra er This li e , which ’ in t is r t t on th e o s su reali y a g ea clef , one of many m on rface , - can be easily seen in a three inch glass . The best time t o view it is or t th e u o t h e s u n is s tt a day so af er f ll m on , when e ing t h e t m h t n t se ts on wes ern li b of t e moon . In forma io he clef

t u t o ou r t n an ons . or rills , as hey are called , are analogo s wes er c y P et a v iu s is especially noteworthy becau se of th e convexity of its

ﬂ t h e t is 8 0 0 t t its s oor, cen re of which fee higher han edge . i It Langrenu s is 9 0 miles in d ameter . cont ains a mou nt ain t t s u t peak 5 8 0 0 feet high . No e t hree small cra er j s northeast t of Langrenu s forming a riangle . - u is e t o i t . Vendelin s p ar shaped , and heref re easily den iﬁed Note a small bu t brilliant crater on th e nort heas tern l pe of F u rn eriu s . h u t t Cl e m s B u rckhardt is th e name of t e crater j s nor h of o ed e .

t it is u in t . I ts s t n Nor h of Gemin s , 5 4 miles diame er we er wall rises t o a height of fee t .

u n t t o s u t u 1 1 0 s . Ga ss , from or h o h , meas res mile P LATE TI

’ Moon s A g e Day s

Peta viu s

9 3 — MOON PLATE III

o -s a Sea of u t th e Sea of t The diam nd h ped Fec ndi y and Nec ar, in r t a e now s . At th e u t t h pen agonal form , vi ible so h of e latter t F ra s ca t oriu s wit its no t o o sea , no e h r h wall br ken d wn . Endy th e s t n is t in I t s mion near we er limb ellip ical appearance . west i i t n s f . . E n t wall places high View dymion 3 d . 7 h . af er h t h u t e 2 a t e oo . new , and d . 9 h . f er f ll m n i . u s t u s s t . n h N W . of Fabrici and Me i a deep clef O t e tip of t h e u t o of th e oon t h e s of the e n t so hern h rn m peak L ib i z Mts . m a y be seen .

. o are n te o t . Tw o Messier , 9 m acr ss , and Messier A o w r hy slightly diverging s treaks ru n east fro m th e latter for a long d is t bu t t e h a a t is t t . s an ance They seem ar iﬁcial, h ir c r c er ill enigma . s t n a in th e S of t t s Alleged change have ake pl ce hape hese cra er . E ast of Proclu s is a pecu liar yellowish-brown pa tch somewhat “ - I t is al d Pa u Somnii or diamond shaped . c le l s , Marsh of a

Dream .

' H ercu l es a nd Atlas are best v iewed 5 or 6 days after th e new

s t th e u . c t moon , or 3 5 day af er f ll moon The former on ains a h f t i is . t e t o s a t it 6 . cr er p , and 4 m across In cen re A las , which

in d mt s u t . 5 5 m . ia e er, ri es a mo n ain

MOON—PLATE IV

t h e t h e Mt s nd th e u N o e t croo ked line of Altai . a Ta ru s and

‘

a u s t 2 . a o t t . H m s range , wi h Pliny 3 m cr ss , be ween hem Dawes u t t lies j s wes of Pliny . E t th e t is t ou o h u s as of Sea of Nec ar a s riking gr p , The p il , i 6 t s u t . s o s I Cyrill s , and Ca harina The former 4 m . acr s . wall

’ i s n i ft . I ts t n places high . cen ral peak can be see beyond i th t h e new . u s s t e t erminator 5 d . af er t moon Cyrill rapezoidal t f its in t . o form and cont ains w o peaks . The N . W por ion h e a f lu wall has been demolished t o make w a y for t w ll o The ophi s .

Posidon iu s on th e west ern S hore of th e Sea of Serenity is 6 2 m . I ts t u t 2 0 0 0 across and cont ains a crater . in erior plain lies abo h th e u t n u t e oo . I t is t 6 . ft . below o e s rface of m n bes viewed d “ h t it is a th e after t e new moon . Nor h of a V sh ped bay called “ ” u i L a cu s Somnioru m or Lake of Sleepers . A pec liar r dge winds it s way from P osidoniu s t o Pliny a cross t h e Sea of Seren u th of os u s is onni w it its t n ity . So P idoni Le M er h eas er wall broken down . ft 13 t l 8 0 0 . Ar a u s . W . Mt . g , N of P iny , 4 high , a ﬁne sigh when th e moon is 5 (1. old . . North of th e Sea of Nectar note Isid ore and Capella with a i t t . s peak over ft . high be ween hem The ring of Capella cu t down by a broad cleft . E th e a u not V t u u s Mara l d i tt o N . . of M re Crisi m e i r vi , , Li r w and Roemer . Sou th of Fabriciu s an d Metiu s are three small craters clos e to

. W . t t u a n V a l c . t gether Pi isc s , Hommel , d q S einheil , N of hem , , ‘ “ is shaped like t h e ﬁgu re 8 P olybiu s and Pons l ie on o ppos ite sides of t h e Alt ai Mt s . PLATE IV

’ Moon s Ag e Day s — MOON PLATE V

h M u rol u s 1 0 t e u t a c m . c a nd St oﬂer are con In so h y , 5 a ross . i ’ s picu ou s . The former s bes t viewed abou t th e time of th e moon s

t u t . A t ul o n it is act ﬁrs q ar er f l m o pr ically invisible . Some its f s t . h of peak are hig . u t t h e t e of th e oon u s t w s t of th e t in to lie Abo cen r m , j e erm a r,

t n u 6 . a ro s a nd t of it u 0 Alba eg i s , 5 m c s , nor h Hipparch s , 9 m . tt t in diame ter. The la er exhibi s signs of demolition and is presu mably older t han Al bat egniu s which is very d eep and com a ra t i el p v y perfect . Note Menelau s a n d Su lpiciu s G allu s on the sou th shore of th e Sea of t t u s t is w n t . I t not n Sereni y , i h Manili be wee hem know t “ ot c t s o cons u ou s t why hese and a few her ra ers are pic ly brigh . u u s Mt a re t ou t of E u o u s s The Ca cas s . prominen s h d x and Ari

t otel es 0 . os s . In th e t th e a is Ca u s ( 5 m acr ) cen re of r nge lipp . The dotted line acros s th e Sea of Serenity repres ents a light

s t t o 2 00 0 m . . t o th e s u t . It reak radia ing from Tych , o hward in t tu t in t h e t of the o s s 1 . cr s e Bessel , 4 m diame er, si a ed mids of t a a t of th e t s t a s on the moon Sea Sereni y . The ch r c er ligh re k n is u known . ul ate eas t of the Cau as u s Mts The small triang ar shaped cr r c . is Th ea t etu s t s ti u s a F en h o s e a s t o , in ere ng beca e r c b rver cl im i n it h ave s een smoke r si g nea r . d u a s I i 0 . n an a o t ts The Sea of Serenity s 4 3 m lo g b wide . a rea is sq . m .

m i 2 . in i t s t n 2 . Godi , 3 , and Agr ppa , 7 m d ame er, re pec ively, th e t n to u t o nt a re ﬁne object s when seen on ermi a r. A min e p i of light is alleged t o have been s een near t hem .

t t s o n a t an . E . S . of Piccolomini are hree cra er f rmi g ri gle h s t "agu t is th e name of t e large .

— M OON PLATE VI

u con s I cu ou s in t he u t I t is 1 0 Clavi s Is p so h . 4 m . across , in a n d its t is ft sq . m . area , a peak on wes ern wall . high . t i i s t t i u Wi h n t walls 9 0 cra ers have been cou n ed . If ts s rrou nd in t t it u o th e is t o g wall were s raigh , wo ld c ver d ance from New Y rk t o u ff B alo . in t is h e t m t . t Tycho , 5 4 m diame er, perfec ly for ed cra er t u t h t t t o e nor h of Clavi s . A sys em of lig s reaks ex ending v r a u t of h e th e t o it q ar er t visible hemisphere of moon radia e fr m .

t . o f u t t t h e t t lie tw o u Nor h Tycho , j s wes of ermina or , gro ps t t t in u con aining three cra ers each . The larges each gro p lies t o th e t nor h . ° n r M Mt s e t t t . The Apennine . , a grand ra g , s ar f om Hadley , E t o th ft . i te t a t t t 0 . e h gh , and rmina e ra os henes 4 5 m E S . .

E t t 8 . is 8 0 00 ft It ont ra os henes , 3 m across , . deep . c ains u u t t hree conspic o s cen ral peaks .

0 u t u 2 t u in Ar . chimedes , 5 , A olyc s , 3 , and Aris ill s , 3 4 m diam h t t l lie th t e s . to the e er respec ive y, nor of Apennine Cassini ,

t t c t tw o t t . t t nor h of hem , on ains cen ral pi s More han ﬁf y it “ h d object s have been detected w hin t e walls of Archime es . th Note th e small peak Linné nor of Mt . Hadley . Alleged n t changes have been noted i i s form . o and o The Alps are pierced by a great cleft 8 0 m . l ng fr m 2 i a t t ft t 6 in t I t s t s . 3 5 o % m . wid h . dep h leas A ria d a u s is connected with Hyginu s by a valley best observed u is t u t th e w t S a t ﬁrst q u arter . Hygin s si a ed on es ern hore of “ ” t h e Mare Vaporu m or Sea of Mists . “ t th e u E s tu u m u t s u t t h e No e Sin s , or G lf of Hea s , o h of

Mare Vaporu m . PLATE VI

' Moon s Ag e Day s

0 Wal ter

OCathari na

O God in

Pos id oni us — MOON PLATE VI I

t C u s n t . t on its t wall No e ich , or h of Tycho A cra er eas ern n only 6 m . across can be see . t of t t t h e u na t t W Wes Bir no e L r Railway or S raigh all , a f c 6 . 1 0 0 0 ft . t or tw o li f line 5 m long and high , bes viewed one days t t h e t u t t th e u u af er ﬁrs q ar er. The wes ern shore of Mare N bi m ,

“ ” ‘ Se a u u t s t h e th e ol d in th e or of Clo ds , o line proﬁle of lady ”

. s E t ot moon Her hooked nose i j u st S . . of P olemy . N e B lli d s u a u 8 . oss 0 0 0 ft . ss e i . 3 m acr , and 9 deep , and Ga nd , 5 5 m n h u s t in t h e i diameter . T ere a re many cu rio clef s wall of

. t it is L etronne its t . Gassendi Nor h of , nor h wall broken down

i n u is cons icu o u s . I t t s 8 nt Coper ic s p con ain ce ral peaks , 3 of n f w t s o e is 2 0 0 t . . hich are brigh one , and 4 high

is t h e s t S ts th e o . t 6 0 . a s Pla o , m cros , one of darke po on m on “ ” u s t h e u t of it not Heveli called i t great black la ke. So h e f i 8 0 0 0 t . Pico h gh . Cape s H era clid es a nd L a Pla ce a re a t t h e eas tern and wes tern “ ext remities respectively of th e Sinu s Irid u m or Bay of Rain ” 1 t is 0 0 0 ft . bows . They are 3 5 m . apar . The former 4 high , and “ ” its s o o th e tt t h e oon i n t had w f rms silhou e e of m ma de , bes viewed when th e moon is I 1 days old . n u s es t i 1 0 The Ca rpathian Mts . ort h of Copernic are b v ewed

n E t t is 2 0 . t h e new . days after moo as of hem Tobias Mayer, m is not a nd 0 0 ft . e . K 2 2 . across 9 7 de p epler , m across , ably bright .

w t n u t of C a u is 1 2 . on ft . Ne o , so h l vi s , 4 m l g and deep , th e deepest crater on t h e moon . ” h u m u s th e Note t e circ u lar Mare H u mor or Sea of H mor , h darkest of t e s eas .

— MOON PLATE VIII

t t h e u o t to th e o u The elescopic view of f ll mo n , con rary p p lar

t is t . th e ﬂ t t no ion , disappoin ing The brilliancy of re ec ed ligh th e t t h e S th e t s dazzles eye , elimina es hadows of grea peak , and s t h e t t t render in eres ing de ails invisible . n h is o t e t 1 8 . 1 2 . o Grimaldi eas ern limb , 4 m long by 9 m br ad ,

' th e t S t h in h e u s t e . o f it t darkes po on moon N . W . Ocean “ u em es t s is i t u th e i t Procellar m or Ocean of T p Ar s arch s , br gh e s t S t t h e . I t is 2 8 o t t po on moon m . across and c nnec ed wi h tu t i t Herodo s by a shor br gh ray . is i tu 2 m . n ts o t Herodo s 4 across . A w i ding valley star fr m c n t h and a be raced across t e sea for a dist ance of 1 0 0 m . t t h e t s t cu th e of th e No e dark pa che wes of Coperni s , color

u s S o m n ii th e t t u A ria d a u s u Pal , brillian cra ers Procl s , , Menela s , i u u u u t u t h e Man li s , S lpici s Gall s , Pico , Aris arch s , and black t s t cra er Pla o and Grimaldi . s theRi h a an Mts n t th e u o u and Ob erve p . or h of Mare H m r m , h H a rbI n er s u t t t . t e g Mt . nor h of Aris arch s The dark pa ch

h e u u t s . n t th e u . t o t s or h of Mare Imbri m , ex ending fr m Ca ca s M “ t o th e u u is t h e Ocean s Procellar m , Mare Frigoris , or Sea of ” t t t o nn t t h e t Cold . The bay ha seems co ec Mare Frigoris wi h th e e u o u t of th e is Oc an s Pr cellar m , nor h Bay of Rainbows , “ ”

th e u u . s u t u Sin s Roris , or G lf of Dews Archimede , A olyc s , and Aristillu s are su rrou nded by an area of a lighter hu e than t hat h u s is c of t e Mare Imbri m . Thi region alled The Marsh of ” Corru ption . All th e sou thern and western portions of th e moon are wanting

in t o to th e nt t t h e t . de ail , wing i ensi y of ligh PLATE VIII

’ Moon s Ag e Days

asendl

1 0 5 OCCULTATION S BY TH E MOON V ISIBLE AT WASH

N T N . C E E R I G O . FO , D , AT CONV NI NT HOURS OBSE RVATION

F ROM E T . 1 1 0 To AN . 1 1 1 1 S P , 9 9 , " , 9

DI S A E A R PP DU R A T I O N A N C E

O ct . 2 0

The time given for th e occultations is the mean t ime

. I i s s for o s s at s t o D . C. t s Wa hing n , nece ary b erver

1 0 6

The Pl a nets

and s ati s fact ory t han any amount Of reading concerning t hem .

As t s oo is o —oo or hi b k pr perly a hand b k , a ready refer

for th e u s e of t h e o s it is on s s ence b erver , ly nece ary t o call att ent ion brieﬂy t o what can be ob s erved of t h e

a t s t th e o t o at ou r o T pl ne wi h p ical p wer c mmand . aking

t h e t s o o t o th e s u n o t up plane In rder , c un ing fr m u ward ,

t h e t st s ou r o plane Mercury ﬁr claim att ent i n .

M E R CU R Y

S o few have ever s een Mercury t hat even th e very s ight

of t t t O - s s is s o of s s o ha plane in an pera gla a urce at i fact i n . The fact t hat it never reache s in it s orbit a dis tance of

o t 2 8 s o t h e su n t t it is m re han degree fr m , and ha never vi s ible for m ore t han t w o h ours aft er s un s et or before

s s o a s it o o s or s th e s u n unri e , acc rding f ll w precede ,

for h i o a ccount s t e fact t hat t is s o s eld m s een . The be st time for s earching for it is when it is farthe st

st or s t of th e s u n f t oo ea we , a ac which any g d almanac

s o - s s s of it s will furni h . An pera gla , becau e large ﬁeld ,

is os t s oo for t o o m u eful in l king Mercury , al h ugh if nce glimp s ed wit h th e naked eye t h e t ele s cope readily

s it it is t t st pick up . In appearance brigh er han a ﬁr f t st s o t s it s s o s . magni ude ar , and me ime eem a reddi h hue ’ The t ran s it s of Mercury acros s t h e s un s di s k average t t s hir een in every hundred year , and are exceedingly

o int ere s ting event s t o watch even with a s mall t ele s c pe . The t ran s it s always occur in t h e m ont h s of May or The Planets

1 a h f h e o . o e 0 w s t e t o t st N vember N vemb r , 9 7, da e la t s t t h e t o o o 6 1 1 ran i , and nex f ur will ccur N vember , 9 4 ; Ma 1 2 o 8 1 2 y 7, 9 4 ; N vember , 9 7 ; and May s o th e s t s t o f s s A ide fr m a i fac ion eeing Mercury , a plea

t t w a s t o Co s t is tt t o ure ha denied pernicu even , here li le int ere st t h e amat eur ast ronomer s ave t o not e th e phas e s t t th e t s s s s t o t os ha plane a ume , which are imilar h e of h oo s in th e t e m n . The cre cent Mercury gleaming

a t of t h e s for th e st w ning ligh dying day , and een ﬁr

is o o o time a s ight never t be f rg tten .

VE NU S

s s o t t o th e is s o a Venu , beau iful unaided eye , al t s o s o t t for s o it s s s ele c pic di app in men , a ide fr m pha e ,

s s o of t st t o o s t which are alway a urce in ere b erve , here are n o s t s t th e of ou r o t o urface fea ure wi hin range p ical p wer . The planet is be s t viewed in t h e twilight o r ju s t before th e th e t t of s s t o dawn , when fain ligh day erve deprive t h e t orb of o t o of it s radian a p r i n brilliancy . Seen under t he s e condit ion s t h e cres Cent Venu s is one of t h e m ost

t o s h e s o s t h e beau iful bject in t heaven . Of c ur e if t ele s o is t o o t ot s c pe equa rially m un ed , b h Venu and Mercury s o can be een in br ad daylight .

MA R S

se of the st o of t he t t of s Becau que i n habi abili y Mar , it mu s t ever be th e mo st int erest ing of t h e planet s t o

t h e t s o o h r mankind , and ama eur a tr n mer a s a neve The Pl a nets

failing s ource of pleas ure in th e ob s ervat ion of many of - th e s urface markings on t h e planet c oncerning which

h a s s o s i there been much dis cu s s ion . Thi s e s pecially

t h e is h t rue When planet neare st t e eart h . The cre s cent phas e never appears in planet s which ’ o o t s th e t s o t bu t at t s s rev lve u ide ear h rbi , ime Mar , s o s th e oo it is t or o appear gibb u like m n , when hree f ur

s o day fr m full .

At o os t o s o o ﬁf fav urable Opp i i n , which ccur nce in t or s t s th e o o s o s een even een year , m re c n picu u dark “ ” s t h e o s s or K s th e marking , H ur Gla ai er Sea , and "

o s o s s t ou r s s . s o p lar n w cap , can be een wi h gla The s o n t e h a s s o called canal , c ncer ing which h re been

o t o s o s t th e st much c n r ver y , can nly be een wi h large

t ele s c o pe s .

2 o A p ower of 00 is recommended . The pre s ent at i n

t 1 0 ll o st o . in Sep , 9 9 , wi be m fav rable

"UPIT E R

s of it s o os s s s in t B ecau e c l al ize , mile diame er ,

it s t is o t h e ost s t s and brilliancy , Jupi er pr bably m a i

o for fact ory of all t h e planet s t o view. in a s mall t ele s c pe ; in addit ion t o t h emarkings on t h e s urface of th e planet

s s th e s th e os which can be ea ily een , rapid change in p i t ion of it s four principal s at ellit e s can be ob s erved t o

v t o s o of s ad an age , and ever pr ve a urce plea ure and

wonderment .

f 1 s is A p ower o 3 0 or t hereabout s h ould be u s ed . There

The Pl anets

t s — s t t is t and hi ever changing cene , ha qui e unique and d ff nt o t s t t s o i ere fr m any hing el e ha human eye beh ld ,

a s s t o o t it t t I s it s ow h a fa cina i n ab u ha peculiarly n .

s t of t h e s s o t t o s t s t s Of The igh eclip e , ccul a i n , and ran i t h e s t t s t h e t s t s of t S o s is of u n a elli e , and ran i heir had w ,

o Th e of t s t s of t h e oo b unded int ere st . view ran i m n s is

f t for s oo st t s bu t t h e s o s di ﬁcul all ave g d in rumen , had w

t s t s s s t t th e is s in ran i are urpri ingly di inc when air t eady . The eclip s e s are accompanied by t h e phenomena of s s n of udden di appearance and reappeara ce , and are all t h e pheno mena of th e s at ellit e s m os t intere sting t o o s b erve .

TH E SATE LLITE S OF J UPIT E R

E U R O P A C A LLI S TO

I d 1 8 . , h .

Colors Whit e The Pl a nets

of ou r oo is 2 1 60 The diameter m n mile s . To as s ist th e st udent in viewing t h e phenomena of t h e s at ellit e s of Jupit er a conden s ed p ort ion of t h e nautical

o for o o almanac relating t heret a braf t ime f ll ws . It h a s been prepared Solely wit h a View t o s ave t h e

st t th e t o of oo t h e t for s uden r uble l king up da a him elf , and t o excit e his int ere st in t hi s fas cinat ing phas e of ob ser

a ion l v t a work .

o s o t for o s t o The h ur given are all c nvenien b erva i n ,

t h e t o of t h e t o s s s o f t h e and veriﬁca i n predic i n , regardle wonderful and beaut iful s ight o f t h e rapidly m oving

s t t s is one of th e t s t s s of th e t a elli e , grea e plea ure ama eur st o o a r n mer . E E THE E E E PH NOM NA OF SAT LLIT S OF JUPIT R, VISIBLE AT WASHINGTON AT TH E TIME INDI GATE D DURING TH E MONTHS OF JULY AND 1 0 TH E E 1 1 0 AUGUST , 9 9 , AND Y AR 9

D A T E PH E N O M E N A

During t h e remainder of t h e year Jupiter is not in a f o favorable p os ition or c onvenient ob s ervati n .

D A T E TIM E S A T E LLIT E P H E N O M E N A

00 . Re .

1 2 0 Ph enomena of S a tellites Of "upiter

TIM E PH E N O M E N A Phenomena of S a tellites of "upiter 1 2 1

PH E N O M E N A

1 9 1 0 1 2 2 Ph enomena o f S a tellites o f "upiter

D A T E PH E N O M E N A

Sept . 3

’ E x pl a na ti on of the P henomena cf j u piter s S a telli tes

The s tudent may have s ome difﬁculty in underst and

t h e o o f th e s at ellit es ' of t ing fully phen mena Jupi er . A

s t of th e on t h e o os t it is udy diagram pp i e page will , h o t e tt . h ped , make ma er clear

1 L et u s s upp ose t hat Fig . repres ent s the View of Jupit er and his moon s in th e t ele s cope us ing the celes tial eyepiece ;

To fully understand t h e real st at e of affairs l et u s

s 2 is s os o h e co . s t at t n ult Fig . The Ob erver upp ed be ’ ” As h e p oint on t h e eart h s orbit marked A . t plane ’ o f t he orbit s o f Jupit er s moon s is pre s ent ed edgewis e

t o s t h e t oo s t o th e ot o ward ear h , each m n appear have m i n o f a pendulum moving forward and back nearly in a t At t s s t of ou r O s t o s t raigh line . hi preci e ime b erva i n , I A i is is t u s t he t t s t . s t be ween and plane , and in ran i a 1 2 4

E xpl a na tio n O f the bright object on a bright background it is practically n u r I s o i vi s ible in o glas s . t S had w h a s not quit e a p ro ch ed t h e o of p a p int ingre s s . I I is ju st t o th e right of th e planet (the t ele s c ope revers ing th e t rue s t at e of affairs ) and is about t o be o c t t h e I c ul ed by planet . t will be s een at once t hat on it s reappearance from o ccultat ion it is immediately

s s o t t it s o t t o eclip ed , ha we have di appear in ccul a i n ,

o s and reappear fr m eclip e . II I is als o a t t he right of t he planet and actually a t ’ u It s s o i t t t h III b t appears at I II . had w s in rans i and e

d ot o i o h black f ts s hadow s h uld be s een on t e planet .

is t o t h e t f th t o t o s IV lef o e plane and ab ut be eclip ed . A careful s tudy of the diagram S hould enable th e s tu dent t o g et a c orrect idea of what is t aking place when he t ob s erve s t h e planet . The nau ical almanac will als o be

of t s s t t he t r r found grea as i ance in making mat e clea .

S A TU R N

Saturn ranks ne x t t o Jupiter in pres ent ing interes ting feature s t o th e p oss e s s ors of s mall tele s c opes . The rings are clearly vis ible and pres ent a marvellous

I ts t o s t oo s t o . w and w nderful appearance large m n , Ti an t t s t t s (in appearance like an eigh h magni ude ar) and Jape u ,

be s oo s o t o s can readily een , and under g d eeing c ndi i n ,

t s o oo s s t t o t he t Rhea , Te hy , and Di ne , m n ill nearer plane , s bu t t he o t s s o can be glimp ed , c mpara ively luggi h m ve

’ 1 2 8 E xpl a nation o f "upi ter s S atellites

t - It is o t a s t t hree inch glas s . ab u brigh a s a s ix h mag nit u d e s tar and c ons equently can be s een with t h e naked

o eye . It will be rec gnized in a t ele s c ope a t once becau s e of t he ab s ence of t h e diffraction ring which always en

th t s of circles e s ar image in a goo d t ele s c ope . The di k

s s f s t t of s t is s Uranu appear pale and di fu ed , ha a ar harp t is s s o t and brillian . The almanac indi pen able in l ca ing it . Light from Uranu s t akes 2 hours and 2 8 minute s t o h reach t e eart h .

t - ss t o of 2 0 t In a hree inch gla wi h a p wer 5 , Nep une l ooks s omething like an eight h magnitude s tar . . It would t ake a cannon s h ot 5 0 0 years t o t ravers e t he o t of t o s t o s s o t rbi Nep une fr m ide ide , peeding c n inually s t s t is t o s s at it s cu s t omary vel ocity . The neare ar h u and

O f times fart her dis tant from t h e eart h than is Neptune .

THE E C C TH E OF LIPTI , SHOWING POSITIONS A E AND A A Y S TURN , JUPIT R , MA RS , J NU R

T FOR E E Y EA . FIRS , TW LV RS

t s on the o s The da e upper , middle , and l wer line indi

t t he os t o s of a t t an d ars res ec ca e p i i n S urn , Jupi er , M p tiv ely .

The movement is from right t o left .

E cl ipti c

1 3 0

The S u n

It is unneces s ary and dangerou s t o l ocat e the s u n by t he u s e of t he a s t tt t he s u n ﬁnder , by experimen ing a li le light can be made t o appear on a paper held clos e t o t he eyepiece . If one can afford it th e mos t s atis fact ory Views of t h e s u n t o t o s o s or os o are be had hr ugh a lar pri m , a heli c pe , which enables t he obs erver t o control th e am ount of

t as s t o t h e e ts of ligh p ing hr ugh eyepiec , and permi a direct View of the s olar phenomena wit hout running any h danger of ruining t e eyes ight . The phenomena of e s pecial intere s t t o the ob s erver t s o th u n wit h a s mall ele c pe are e s s p ots . There is s el d om a t ime when t here are not on e or more s p ots on t h e s u n t he s t o ot t t , and change be n ed in hem , and heir ’ t ot o cr os s t h e s s s apparen daily m i n a un di k , are well cal cu l a t ed t o intere s t t he s tudent ; e s pecially when he con

s t h e t of of t he s ot s a s s ider magni ude many p , he can well d o o n t t t he t of the s u n h by c mpari g hem wi h diame er , whic is miles . The mean rot at ion perio d of the s u n is twenty-ﬁv e

’ he t he ots t os s th s . t s e s s day On average , p ravel acr un t dis k in a little over four een days .

The s p ot s often change perceptibly from day t o day .

o o t t s ot s t o S me are bli era ed in a few day , while her appear

i t t s e for s s s s o s remain n ac , and are en everal ucce ive peri d

It is oo t t o S t t h e s ots a s of revolution . g d prac ice ke ch p

t s t he s t t hey are ob s erved . In hi way change in heir t appearance can be eas ily no ed . The S u n

E xcellent Views of t h e s p ot s may be had t hrough t h e o s s t t t h e s s of t h e s lar eyepiece , by in er ing be ween len e

iece of o h a s o regular eyepiece a p g cardb ard , which a h le t -h pierced t hrough its centre wi h a red ot needle . This met hod brings t o light c o ns iderable det ail . It ha s been determined t hat t he magnitude and num ber of t he s p ot s wax and wane in a perio d of ab out eleven

a t t h e s s of th e years . Ne r a minimum ime Vi ible urface s u n o s ot s for s at may be free fr m p week , while maximum t s os t s o l hey can be een alm every day , me being arge e nough to be s een t hrough a s moked glas s wit h t he naked — w a s o t 1 0 0 . eye . A maximum reached ab u 9 4 5

AS t o t he t of the s ot s no t o a s et ro na ure p , he ry y p th o h n p ounded fully explains e phen mena . It a s bee o s t t o s of s u n s ots b erved ha during maximum peri d p , magnetic s t orms on the eart h and dis plays of t h e aurora

o s t o s o t t o t t b reali frequen ly ccur , ha in all pr babili y here i o s s me connection between t hem . E clips e s are of cours e of t he greate s t intere st to o s of s o o s t h e t ot b erve all lar phen mena , e pecially al

s s o t t s o o . eclip e , which unf r una ely eld m ccur In regard t o t t h e c s t he s s t a s hem , almana will upply nece ary da a t o t s ime and vi ibility . - The s o called s olar prominence s are the most s pect a c of h s o - ular all t e lar phenomena . They are geys er like o t s of o h as t t s t ou t f un ain hydr gen and elium g , ha pur ’ o t he s s s s o t ms s t o t o fr m un urface , me i e ri ing a heigh f

’ 3 mile s . They can only be s een when on t h e s un s The S u n

t o t o s t os o . It i limb , and hen nly hr ugh a pec r c pe s p os s ible t o attach a S pectros c ope t o a glas s of only t hree inch aperture and s urely t o one w h o can afford s uch a luxury t he s pectros cope t hus employed will yield a mine of enj oyment . The matter of s olar Obs ervation is merely hint ed at here . There Is a wealth of material on t h e s ubject a t t h t h It is o n s s t o e c ommand of e s tudent . nly ece ary call attention to t h e danger of ob s erving t he s u n with o u t interp os ing a s emi-o paque medium and t o men - t ion brieﬂy t he phenomena obs erv able in a t hree inch t eles cope . As tronomers are paying more attention t o the s u n at

it i t h s t pres ent t han ever before . The fact t hat s e neare s tar t o the eart h renders it mos t wort hy of ou r Ob s erva tion and every new fact relative t o it s nature and t he character of its phenomena is of prime imp ortance to t he race . Becaus e of the s trides n ow being made in s olar photog ra h t is s o t o o t t t he p y , here every rea n h pe ha in very t he t of th e s u n S ots at s t be near fu ure t na ure p , lea , will revealed .

Ind ex to the Co ns tellatio ns

t 6 1 Lacer a , L eo I , 3 s Lepu , 77 2 Libra , 5 I Lyra , 5 o o os M n cer , 79 s s 2 Ophiuchu and Serpen , 7 o 8 1 Ori n , s s E s 6 1 Pega u and quuleu , s s 6 Per eu , 3 s s 6 Pi ce , 5 tt 2 Sagi a , 9 tt s 1 Sagi ariu , 3 o o Sc rpi , 3 3 s 2 Serpen , 7 s 6 Tauru , 7 1 Triangulum , 4 s o Ur a Maj r , 3 5 s o Ur a Min r , 3 7 o 1 Virg , 7 I NDE " TO THE MOO N O N TH E D IAGRA MS

Craters 8 Agrippa , 9 t s 8 Alba egniu , 9 Al ia cencis , 99 o o s Ap ll niu , 93 A r s I o o chimede , Aria d a u s 1 0 0 1 0 , , 4 s t s 0 1 0 Ari archu , 9 , 4 s t s I o o Ari illu , st ot s 8 Ari ele , 9 I O I Arzachel , t s A la , 94 t o c s 1 0 0 Au ly u , o t Beaum n , 9 7 s s 8 B e el , 9

Biela , 97 t 1 0 2 B ir , Bl a n chini 1 0 , 3 o 1 0 B npland , 3 B u llia d u s 1 0 2 1 0 , , 5 t 2 Burckhard , 9

Burg , 97 C s 8 alippu , 9 C 6 apella , 9 C s 1 0 apuanu , 3 Ind ex to the Moon Diagra ms

C s s 1 0 0 a ini , C t 6 a harina , 9 C s 1 0 2 ichu , C s 1 0 0 laviu , Cl eom ed es 0 , 9 Co o t nd rce , 93 Co s 1 0 2 pernicu , C s 6 yrillu , 9 s 6 Dawe , 9

Delambre , 99 E o ndymi n , 94 E t os t s 1 00 ra hene , E o s 8 ud xu , 9 s Fabriciu , 94 t Ferma , 97 s ' Firmicu , 93 s t 1 0 Flam eed , 5 Fra o 1 0 Maur , 5 Fra s ca t oriu s , 94 F s 2 urneriu , 9 s s 1 0 2 Ga endi , s s 2 Gau , 9 s 2 Geminu , 9 Fris iu s Gemma , 99 o 8 G din , 9 0 1 0 Grimaldi , 9 , 4 o 1 0 Helic n , 3 s Hercule , 94 H o ot s 1 0 er d u , 4 s 1 0 1 Her chel , s 1 0 2 Heveliu , s 8 Hipparchu , 9 H o 6 mmel , 9

1 44 Ind ex to th e Moon Diagra ms

o s 6 P lybiu , 9 o s 6 P n , 9 os o s 6 P id niu , 9 o s 1 0 Pr clu , 94 , 4 t o 1 0 2 P lemy , 1 0 1 Purbach , t s 1 0 Py hea , 3 o 1 0 Reinh ld , 5 t Rhei a , 97 o 6 R emer , 9 t San bech , 97 1 0 Scheiner , 3 s 1 0 1 Silber chlag, St a d iu s 1 0 , 3 t S einheil , 97 t o s S ib riu , 97 StOﬂer 8 , 9 t t 1 0 S ree , 3 s s 8 Sulpiciu Gallu , 9 T t s arun iu , 97 o Tayl r , 99 h ea t et u s 8 T , 9 o s 6 The philu , 9 o s 1 0 Tim chari , 3 o s 1 0 2 T bia Mayer, s 0 Tralle , 9 o 8 Tych , 9 Val c 6 q , 9 s 2 Vendelinu , 9 t s 6 Vi ruviu , 9

Werner , 99 1 0 Wilhelm I , 3 " t 8 agu , 9 I nd ex to the Moo n on the Di agra ms 1 4 5

Mountains

s 1 0 0 Alp , t 6 Al ai , 9 s 1 0 0 Apennine , C t 1 0 2 arpa hian , C s s 8 auca u , 9 H a s 6 mu , 9 1 0 Harbinger , 4 n t Leib i z , 94 Ri h a an 1 0 p , 4 s 6 Tauru , 9

Mt . a n s 6 Arg , 9

Mt . 1 0 0 Hadley ,

S zas

C s of Co ﬂ t s 0 Mare ri ium , Sea n ic , 9 t t s t Fecundi a i , Fecundi y , 4 Q 9 o s Co 1 0 Frig ri , ld . 4 H o H o s 1 0 2 um rum , um r , s 1 0 Imbrium , Rain , 4 t s t Nec ari , Nec ar , 94 C o s 1 0 2 Nubium , l ud , t t s t 8 Sereni a i , Sereni y , 9 Tra n u ilitatis t q , Tranquilli y , 9 7 o s t s 1 0 0 Vap rum , Mi , - s o of s t s 1 0 Oceanu Pr cellarum , Ocean Tempe , 4

Capes

C 0 ape Agarum , 9 H era clid e 0 s , 1 2 1 0 2 La Place , 1 46 In d ex to the Moo n o n the Di agra ms

B ays and Gulfs

s Ai s t u u m of Het s 1 0 0 Sinu , Gulf a , of o s 1 0 2 Iridum , B ay Rainb w , o s of 1 0 R ri , Gulf Dew, 4

Oth er Formations

L a cu s o o of t h e s 6 S mni rum , Lake Sleeper , 9 o or t t 1 0 2 Lunar Railr ad , S raigh Wall , s S om nii s of Palu , Mar h a Dream , 94 s t s s o f Co t o 1 0 Palu Pu redini , Mar h rrup i n , 4

o f th e

ta r s

William Tyler “ A u th o r o f I n S t a r l a n d w i th a T h r e e -i n c h

e l e c ae e c T s o y , t .

With ver 5 Il u r ns l s t a tio a nd ha rts . n o 0 C et .

T o facilitate th e fas cinating recreation o f s tar

a z th e t o h as d s e t s oo g ing , au h r e ign d hi ﬁeld b k. A ll m atters of a technic al o r theoretic a l na ture

a o m tt a h e ea e c an h ve been i ed . Only w h t t r d r - obs erv e w ith th e naked ey e or w ith an Opera gl as s

a u it S im lic 1t t h ve been incl d ed in . p y and brevi y

a e m d at th e ma d ea n t a t w h a t h ve b en ai e , in i bei g h

' ever is bulk y or verbos e is a hindran ce rath er th an a h elp w hen o ne is engag ed in th e obs ervation o f th e a s he ven .

NA M ' S S O NS G . P . PU T

New Yo rk L o n d o n