Site name Description Web site address NexStar Resource Site The author's website www.NexStarSite.com NexStar FAG Site Articles and tips for NexStar www.grcooperjr.com/faq.htm telescopes Yahoo NexStar Group Discussion groupfor all groups.yahoo.com/group/ models of NexStar telescopes NexStar Yahoo NexStarGPS Discussion group for the GPS groups.yahoo.com/group/ Group models of NexStartelescopes NexStarGPS NexStar 50 Club Web sitefor the NexStar 50 www.NexStarSite.com/ observerclubs - awardsare nexstar50club.htm given for a generallist afobjects and observa tionof lunar features N exStarmage I Gallery A collection ofhundredsof www.buyastrostuff.com/dons imagestaken with all modelsof NexStar telescopes Matthias Bopp's Site A unique collection of technical www.dd 1us.de informationand tips for NexStartelescopes The Unofficial NexStar Dave Cole's web sitefeaturing www.nexstarl1.com 11 SupportSite tips and resources for the NexStar ~/1 1 GPS telescopes Celestron's Web Site Official web siteof Celestron, www.celestron.com manufacturerof NexStar telescopes Celestron's Download Productmanuals and other www.celestron.com/ Site downloads downloads/index.htm
259 260 The NexStar User's Guide
Site name Description W eb site a ddress American Associat ion of Web site of the Association - www.corvus .com Amateur Astronomers general astronomy information Astronomical league Web site of the league - an www.astroleague.org organization for amateur astronomers, general astronomy information, observation programs and awards Astronomy Magazine Web site of Astronomymagazine • www.astronomy.com news and general information for amateur astronomers Cloudy Nights Equipment reviews submitted by www.c1oudynights.com Telescope Reviews amateur astronomers NASA Web Site Officialweb site of the United States' www.nasa .gov National Aeronautics and Space Administration ScopeReviews .com Equipment reviews by Ed T ing www.scopereviews.com Sky and Telescope Web site of Sky and Telescope skyandtelescope .com magazine - news and general informationfor amateur astronomers SkyMaps Free mon thly sky charts www.skymaps .com Students for the Great source of informationon solar seds.lpl.arizona.edu Exploration and system, deep sky objects, and Development of Space general astronomy
Vendor and Manufacturer Web it -"< .' " ',' ," .... ,."
Company Products - notes W eb site address Adirondack Video CCD and v ideo cameras , automated www.astrovid.com Astronomy focusing software, imaging accessories Adorama Telescopes , accesso ries www.adoramaphoto.com Alpine Astronomical The Baader Bracket, Baader astre• www.alpineastro.com photography adapters , other accessories Anacortes Telescopes Telescopes , accessor ies www.buytelescopes.com Apogee Instruments CCD astronomy cameras www.ccd.com Apogee, Incorporated Telescopes , accessories www.apogeeinc.com AstroMart Used equipment; you can both buy www.astromart.com and sell Internet Resources 261
Company Products - notes Web site address
Ast ronomics Telescopes, accessories www.astronomics.com Astronomy-Mall A short listing of astronomy vendors and astronomy-mall.com free classified ads for astronomy equipment Astro-Physics Diagonals, Baader Solar Film, Baader www.astro-physics .com Color Filters, Baader Skyglow Filter, portable piers Baade r Planetarium Telescopes , the Baader Bracket, filters, www.baader· astrophotography accessories , planetarium.de other accessories BuyAstroStuff .com Ray's Bracket, observing cha irs www.buyastrostuff.com Campmor O utdoor equipment supplier www.campmor.com Cases and Covers You guessed it - telescope cases casesandcovers .com and covers Coleman Out door equipment supplier www.coleman.com Coronado HAlpho solar filters www.coronadofilters.com GRABBER Warmers Chemical hand warmers www.grabberwarmers.com Hands On Optics Telescopes , accessories www.handsonoptics .com ITE Telescopes C CD and video cameras , other www.itetelescopes.com accessories Jim's Mobile, Inc. UMI) Telescope accessories www.jimsmobile.com Kendrick Astro Dew prevention systems, other www.kendrick-ai.com Instruments accessories Losmandy Rails, counterweights, mounting www.losmandy.com accessories Morrow Technical Bob 's Knobs (no-tools collimation www.bobsknobs .com Serv ices screws for SCTs). no-tools tripod bolts for the N8/1 1GPS Optec Focal reducers (telecompressorsl www.optecinc.com/ astronomy Orion Telescopes Telescopes, accessories www.telescope.com and Binoculars Pelican Cases Telescope cases www.pelican.com Peterson Engineering EyeOpener 2" adapter for SCTs www.peterson-web .corn REI Outdoor equipment supplier www.rei .com S . King Company A co llectionof 12V d .c. www.skingco.com convenience equ ipment SAC Imaging Video astronomy cameras www.sac-imaging.com Santa Barbara CCD astronomy cameras www.sbig.com Instrument Group (SBIGI ScopeGuard Cases Telescope cases www.scopeguard .com ScopeStuff Accessories www.scopestuff.com 262 The NexStar User's Guide
Company Products - notes Web site address ScopeTronix Digita l cameraadapters, other www .scopetronix.com accessories S ightAndSoundShop Telescopes, accessories www.sightandsound shop.com SKB Golf casessuitablefor some www.skbcases.com telescopesand tripods Starizona Telescopes, accessories www .starizona.com Starlight Xpress CCD as tronomycameras www .starlight- xpress.co .uk Tele Vue Telescope, eyepiece, and accessory www .televue.com manufacturer The Telescope Unique astronomyaccessories www .astronomy- Warehouse mall.com/telescope-ware house Thousa ndOaks Filters www .thousandoaks optical.com UniversityOptics Eyepieces, Barlow lenses www .universityoptics.com Van Slyke Engineering Zero-image-shiftfocusers, off-oxis www .observatory.org guiders WarehousePhoto T-mountsand variouscamera www .warehousephoto.com/ adapters lenses&.htm W illiamOptics Telescopes, accessories www.william-optics.com The objects in the NexStar database areorganized byseveralcategories.Several ofthecat• egoriesare thewell-knowncatalogs discussed inChapters 2and 6.
Named Stars (Alignment Stars)
The brighteststars in the sky are listed, primarily for use asalignmentstars.
Nam e RA Dec M ag Constellation
Achernar Olh37m43' -57°14' 0.6 Eri Acrux 12h26m36' -63°05' 1.6 Cm Albireo 19h 30m43' +27 °58' 3.2 Cyg Aldebaran 04h35m55' + 16°31' 1.1 Tau Algenib OO h 13m14' + 15°11' 2.9 Peg Alpha Centauri 14h39m36' - 60°50' 0.0 Cen Alphard 09h27m35' -08°39' 2.2 Hya Alphecca 15h34m41' +26 °43' 2.3 CrB Alpheratz OO h08m23' + 29°06' 2.1 And Altair 19h50m47' + 08° 52' 0.9 Aql Antares 16h29m24' -26°26' 1.1 Sco Arcturus 14h 15m40' + 19°13' 0.2 Boo Betelgeuse 05h 55m10' +0 7°24' 0.6 Ori Canopus 06h23m57' -52°42' - 0.9 Car Capella 05h 16m41' +46 °00' 0.2 Aur Caph OO h09m11' + 59°09' 2.4 Cas Castor 07h34m36' + 31° 53' 1.6 Gem Deneb 20h41m26' +45 °17' 1.3 Cyg Denebola Il h49m04' + 14°34' 2.2 Leo Dubhe Il h03m44' +61°45' 2 Uma Fomalha ut 22h57m39' -29°37' 1.3 PsA Hadar 14h03m50' - 60°23' 0.9 Cen Hamal 02h07m10' + 23°28' 2.2 Ari Mim osa 12h47m43' - 59°41' 1.5 Cru M irach Ol h09m44' +35 °37' 2.4 And
263 264 The NexStar User's Guide
Mi rfak 03h24m 19' + 49°52' 1.9 Per Mizar 13h 23m 56' +54°55' 2.4 Uma Navi OOh 56m 43' + 60°43' 2.8 Cas Peacock 20h25m 39' -56°44' 2.1 Pay Polar is 02h31m 50' +89°16' 2.1 Umi Pollux 07h45m 19' +28°02' 1.2 Gem Procyon 07h39m 18' +05°14' 0.5 Cmi Rasalhague 17h34m 56' +12°34' 2.1 Oph Regulus 10h08m 22' + 11°58' 1.3 Leo Rigel 05h 14m 32' - 08°12' 0.3 Ori Scheat 23h3m 46' +28°05' 2.6 Peg Sirius 06h45m 9' - 16°42' - 1.6 Cma Spica 13h 25m 12' -11 °10' 1.2 Vi r Suhai l 09h08m 00' - 43°26' 2.2 Vel Vega 18h36m 56' +38°47' 0.1 Lyr
Double Stars
The reare 55 double sta rs in theNexSta r datab ase. Additio nal double stars can be accessedwiththe Star button on the handcontro l.Lis ts ofthose stars (h undre dsfor the GT, thou sands for theother NexS ta r models) are available in the Downloa ds sectio n of my NexStar Resource Site - http://www.NexStarSite.com.''
Nam e Ra Dec Mag Sep/Pos angle Constellation
107 Aqr 23h46m 01' - 18°41' 5.8 7" 1143° Aq r 145 Cma 07h 16m 36' -23°19' 4.8 27" 1 65° Cma 17 Cyg 19h46m 26' +33°44' 5.0 26" 173° Cyg 19Lyn 07h22m 54' +55°17' 5.6 14.8" 1 315° Lyn 24 Com 12h35m 08' + 18°22' 5.2 20"/271° Com 30 Ari 02h37m 00' +24°39' 6.6 39" 1 274° Ari 32 Eri 03h54m 18' - 02"57' 5.0 7" 1 347° Eri 35 Com 12h53m 18' +2 1°15' 5.1 29" 1Trip le Com 38 Gem 06h54m 39' +13°11' 4.7 7" Gem 54 Leo 10h55m 37' + 24°45' 4.5 6.8" 1 110° Leo 61 Cyg 2l h06m 36' +38°42' 5.4 30" 1 148° Cyg 94 Aqr 23h 19m 07' - 13°27' 5.3 13" 1350° A qr 95 Her 18hoi- 30' +21°36' 5.1 6.5" 1 258° Her Acamar 02h58m 16' - 40°18' 4.4 8" 182° Eri Adh ar a 06h58m 38' - 28°58' 1.6 7.5" 1 161° Cma Albireo 19h30m 43' + 27°58' 3.2 35" 154° Cyg Algieba IOh 19m 58' + 19°50' 2.6 4.4" 1 124° Leo Algorab 12h29m 52' - 16°31' 3.1 24" 1 214" Cry Almac h 02h03m 55' +42°20' 5.1 10" 163° And Beta Mo n 06h28m 49' - 07°02' 4.7 3" 11 32° Mo n Casto r 07h34m 36' +31°53' 1.6 1.8" 1171° Gem Cor Caro li 12h56m 01' +38°19' 2.9 19" 1 229° CVn Dabih 20h21m 01' - 14°47' 3.3 205" 1 267° Cap Delta Cep 22h29m 10' +58°25' 4.0 20" 1192° Cep Delta Ser 15h34m 48' + 10°32' 5.2 3.9" 1 179° Ser Epsilon Boo 14h44m 59' + 27°05' 2.7 3" 1 303° Boo Epsilon Lyr I 18h44m 20' +39°40' 6.0 2" 1 353° Lyr Epsilon Lyr 2 18h44m 23' +39°37' 4.5 2.2" 1 80° Lyr Epsilon Peg 21h44m 11' +09°53' 2.5 83" 1 320° Peg Objects in the NexStar Hand Control 265
Eta Cas OOh 49m 03' + 57°49' 3.6 12" /312° Cas Eta Puppis 07h 34m 20' -23°28' 5.9 10" /117° Pup GammaAries Olh 53m 30' + 19°19' 4.8 8" /360° Ari GammaCet 02h 43m 18' +03°14' 3.6 2.7" /297° Cet Graffias 16h 05m 26' -19°48' 2.9 14" /21° Sco IotaCancer 08h 46m 42' +28 °46' 4.2 31" /307° Cnc Kappa Boo 14h 13m 29' +51°47' 4.6 13" /236° Boo Kappa Puppis 07h 38m 48' - 26°48' 4.6 10" /318° Pup Lamda Aries Olh 57m 54' + 23°36' 4.8 38" /47° Ari Mintaka 05h 32m 00' - 00°18' 2.5 53" Ori M izar 13h 23m 56' + 54°55' 2.4 14"/151° Uma Nu Dra 17h 32m II ' +55°11' 5.0 62" /312° Dra Omicro nCap 20h 29m 54' -1 8°35' 6.1 19" /239° Cap Polaris 02h 31m 50' +89°16' 2.1 18" /218° Umi Porrima 12h 41m 40' - 01°27' 2.9 3" /287° Vi r Psi Piscium Olh 05m 42m + 21°28' 5.5 30" /159° Psc Rasalgethi 17h 14m 39' +14°24' 3.5 4.6" /107° Her Rigel 05h 14m 30' - 08°12' 0.3 9" /203° Ori Sigma Cas 23h 59m 01' + 55°45' 4.9 3" /326° Cas Tau I Aqr 22h 47m 43' - 14°03' 5.7 23" /121° Aqr Tegman 08h 12m 13' + 17°39' 6.0 9" /89° Cnc Theta 2 Cnc 08h 26m 48' +26°56' 6.3 5" /217° Cnc Xi Boo 14h 51m 23' + 19°06' 4.6 7" /326° Boo ZetaAqr 22h 28m 50' +00°01' 4.6 2" /207° Aqr Zeta Lyr 18h 44m 46' +37°36' 4.3 44" / 150° Lyr Zeta Piscium 01h 13m 42' +07°35' 5.6 23" /63° Psc
Variable Stars
The hand control databaseincludesa small selectionof the most interesting variablestars.
Name RA Dec Min Max Period Constellation mag mag in days Algol 03h 08m 10' +40°57' 2.2 3.5 2.9 Per Beta Lyr 18h 50m OS ' + 33°22' 3.5 4.3 12.9 Lyr Delta Cep 22h 29m 10' +58°25' 3.6 4.3 5.4 Cep L Car 9h 45m 15' - 62°30' 3.4 4.1 35 Car Mira 02h 19m 21' - 02°59' 3.4 9.2 332 Cet R Car 09h 32m 15' -62°47' 4.6 9.6 309 Car R Cen 14h 16m 34' - 59°55' 5.9 10.7 546 Cen R Cyg 19h 36m 26' +50°13' 7.5 13.9 426 Cyg R Dra 16h 32m 39' +66°45' 7.6 12.4 246 D ra RH or 02h 54m 06' - 50°52' 6.0 13.0 404 Hor RLeo 09h 47m 34' +U026' 5.8 10.0 312 Leo R Tri 02h 35m 47' +34°41' 6.2 11.7 266 Tri RRL yr 19h 25m 27' +42 °47' 7.3 8.1 0.6 Lyr SCar IOh 09m 22' - 61°33' 5.7 8.5 150 Car SS Cyg 21h 42m 34' +42°26' 8.2 12.4 50 Cyg h TCen 13 41m 46' -33°36' 5.5 9.0 91 Cen TCep 21h09m 32' +68°30' 6.0 10.3 388 Cep h UGem 07 ssm 06' + 22°40' 8.2 14.9 103 Gem UU ma IOh 44m 38' +68°46' 7.5 13.0 302 Uma Zeta Gem 07h 04m 07' +20°34' 3.7 4.3 10.2 Gem 266 The NexStar User's Guide Named Obiects
A l istingof some of the mostspectacular deepsky objects.
Name RA Dec Mag S ize Type Const Comments
Andromeda OOh 42.7ffi +41°16' 3.5 178' Gal Andromeda M31. The closest spiral GaiaxyM31 galaxy to earth. Spanning3°across, the Andro medagalaxy is thefarthest objectthat can be seenwith the nakedeye. Distance= 2.8million Iy. Diameter = 180000 Iy. Barnard 's 19h 44.9ffi -14°48' 9.0 10.2' Gal Sagitt ariu s Irregular dwarfgalaxy. Galaxy D istance = 1.7milly. NGC 6 822 Diameter=10000 Iy. Bear Paw 08h 13.2ffi +46°00' 11.7 1.7' Gal Lynx Moderatelybright, Galaxy round,and well-resolved NGC 2537 galaxy. Beehive OC 08h 40.l ffi + J9059' 3.1 95' OC Cancer Opencluster containing M44 over 200 stars,visible to the naked eye.Also called Praesepeand M44. Distance=525 Iy. Diameter=40 Iy. Black-Eye 12h 56.7ffi +21°41' 8.5 9.3' Gal Coma A spiral galaxy with a GaiaxyM 64 Berenices strikingdark dust cloud nearthe central nucleus. Dis tance=20 million Iy. Blinking Plan 19h 44.Sffi +50°31' 10.0 2.3' PN Cygnus Planetary nebuladisc NG C 6826 with 11th-magnitude centralstar. Blue Planetary II h 50.3ffi - 57°11' 8.0 0.2' PN Centaurus Small,roundplanetary NG C 3918 nebula. Blue in color with 7th-mag nitudestar in center. Blue Snowball 23h 25.9ffi +42°33' 9.0 2.2' PN Andromeda A h azy blue planetary NGC 7662 nebulaestim atedto be 1800 to 5600 Iy away and 20000 to 50000 AU across. Bode's Nebula 09h 55.6ffi +69°04' 6.9 25.7' Gal Ursa Major A mas sive galaxy witha M8 1 luminosity equalto 20 billionsuns and a total mass of approx 250solar masses.Distance7 millionly. Diamet er=36000 Iy. Box Nebula 17h 14.1ffi - 12°55' 11.0 1.1' PN Ophiuchus This planetary nebula NG C 6309 has a greenishdisk and appea rs rectangularin shape, henceits name. The Box Nebula isbest seen using an 0 III nebula filter. BubbleNebula 23h 20.7ffi +61°12' 15' SR Cassiopeia Remnantof a supernova, NGC 7635 namedfor its gaseousarc Objects in the NexStar Hand Control 267
Name RA Dec Mag Size Type Const Comments thatresemblesa large bubble. Distance= 11000 ly. Bug Nebula 17h 13.7ffi -37°06' 13.0 0.8' PN Scorpius Irregular-shaped NGC6302 planetarynebula. ButterfiyOC 17h 40.1ffi -32°13' 4.2 15' OC Scorpius Also called M6.Bright M6 open clustercontaining about50 stars. Distance= 1300ly. Diameter= 20 ly. California 04h 00.7ffi +36°37' 145' Neb Perseus Very faint, large,and Nebula diffusenebula NGC 1499 resemblingtheshapeof Californ ia.Best seen using ahydrogen-beta filter. Cat's Eye l7h 58.6ffi +66°38' 9.0 5.8' PN Draco One of thebrightest Nebula planetarynebulaewith a NGC6543 centralstar nearly 100 times theluminosityof the Sun. Distance= 3200 ly. Diameter= 0.33 ly. h Christmas 06 4I.lm +09°53' 3.9 60' OC Monoceros A very young open Tree cluster,also called the NGC 2264 Cone Nebula, with 150 memberssurroundedby darknebulosity. Distance= 2600 ly. Diameter= 20 ly. Cocoon 21h 53.4ffi +47°16' 7.2 12' Neb Cygnus A faint openclustersur- Nebula roundedby nebulosity IC 5146 that islocatedESEof a largedarknebula- Barnard168. Crab Nebula 05h 34.5ffi +22°01' 8.4 6' SR Taurus Also called Ml. Ml Supernovaremnantthat was recordedby the Chinese in the year 1054. At its brightest,it was visible evenin the daytimeand cast a shadowin thenighttime. Distance= 6500 ly. Diameter= 10 ly. Crescent 20h 12ffi +38°21' 20' Cygnus A faint, very large Nebula nebularwith adouble NGC6888 starvisible inside. Best seen with an OlII filter.
Deer Lick 22h37.1ffi +34°25' 9.5 10.7' Gal Pegasus A fairly brightelongated Galaxy galaxy with four small NGC 7331 companiongalaxies sur- roundingit. Double 2h 19ffi +57°09' 4.0 30' OC Perseus Two openclusters Cluster visible 268 The NexStar User's Guide
Name RA Dec Mag Size Type Const Comments NGC 869/884 to thenakedeye, each with a diameterof about 70 ly.Both clustersare veryyoung.NGC 884 is 8500 ly in distanceand 11.5 million years old. NGC 869 is 7000lyaway and 6.4millionyears old. Dumbbell 19h59.6ffi + 2Z043' 8.1 15.2 PN Vulpecula One of theclosest NebulaM27 planetary nebulaeto earth.Expandingat a speed of 27 km/s,it can be estimatedto beabout 48 000 years old. Distance= - 750 ly. Diameter = 2 ly. Eagle Nebula 18h 18.8ffi -13°47' 6.0 35' Neb Serpens A large opencluster MI6 surroundedby a diffuse nebula.A very active region ofstarformation. Distance= - 8000 ly. Diameter= 70 ly. Eight Burst 10h07.0ffi -40°26' 8.0 0.8' PN Vela Bright central star. Nebula Namedafterits multi- NGC 31 32 ring structure visible in photographs. Distance= 2500 ly. Diameter=0.7Iy. Eskimo 07h29.2ffi +20°55' 10.0 0.7' PN Gemini Bright innerring Nebula separatedby a darkgap NGC 2392 from anotherfaint outer ring. Distance= approx. 2500 ly. Ghost Of 10h24.8ffi -18°38' 9.0 20.8' PN H ydra Planetary nebula with an Jupiter elongated inner ring. NGC 3242 Distanc e= - 2600 ly. Diameter =0.5 ly. Helix Nebula 22h29.6ffi -20°48' 12.8' PN Aqu ariu s The largestand closest NG C 7293 planetary nebulawith an angulardiameterof half the full Moon. Distance= - 300 ly. Diameter= 1.751y. Hercules GC 16h41.7ffi +36°28' 5.9 16.6' GC He rcules Globularclustervisible to M13 thenakedeye. The cluster contains about I million stars and isestimatedto be 10billionyears old. Distance= 25 000ly. Diameter= 160 ly. Hind 's 04h22.9ffi +l9°32m Neb Taurus Very faintreflection Variable nebula. Nebula NGC 1555 Horsehead 05h41ffi -OZ024' I I.3 60' Neb Orion A darknebula that Nebula resembles theshapeof a IC 434 horse head, positionedin frontof a brightdiffuse Objects in the NexStar Hand Control 269
Name RA Dec Mag Size Type Const Comments nebula.This objectis best seen using an H-Beta filter.Distance= 1500 Iy. Hubble 06h 39.2m +08°44' 2' Neb Monoceros Gaseous nebula Variable surroundinga variable Nebula star.Distance= 2600 Iy. NGC 2261 Diameter= 7 Iy. Hyades 04h 27.0m +16"00' 4° OC Taurus A very close opencluster NGC 7845 with atriangularshape forming the head of the bull of theconstellation Taurus. Distance= 150Iy. Diameter= 121y. Lagoon 18h 03.8m -24°23' 5.8 90' Neb Sagittarius A very brightnebula NebulaM8 which is an activestar formationregion. Distance= 5000 Iy. Diameter= 100Iy. Little 01h 42.3m +51°34' 12.0 4.8' PN Perseus Dumbbell NGC 650 NGC 891 02h 22.6m +42°21' 10.0 13.5' Gal Andromeda Edge-on spiral galaxy with prominentban of darkinterstellarmatter along the galactic plane. Distance= 43 million Iy. Diameter= 120000ly, North 20h 58.8m +44°20' 120' Neb Cygnus A diffuse nebulathat American resemblestheoutlineof Nebula theNorthAmerican NGC 7000 continent.Best seen with an om filter. Distance 1600 Iy. Diameter451y. Omega Cluster13h 26.8m -47°29' 3.7 36.3' GC Centaurus The brightestand largest NGC 5139 globularclusterin the sky. Best seen at lower or southernlatitudes. Distance = 17000 Iy. Diameter= 100 Iy. Orion Nebula 05h 35.4m -05°27' 4.0 66' Neb Orion One of the most M42 impressivediffuse nebulaein the sky. Visible to thenakedeye bellowOrion's belt. Star formingregion with four prominentstars called "The Trapezium" centeredin thenebula. Distance= 1600Iy. Diameter= 30 Iy. Owl Nebula llh 14.8m +55°01' 11.2 3.2' PN Ursa Major Also called M97.1rregular M97 shapedplanetarynebula. Distance= -3000Iy. Diameter= 3 Iy. Pinwheel 01h 33.9m +30°39' 5.7 62' Gal Triangulum A large spiralgalaxy M33 structurewithbright knotsof dustandgas. 270 The NexStar User's Guide
Name RA Dec Mag Size Type Const Comments After the Andromeda Galaxy, itis the closest spiralgalaxy to theMilky Way. Distance= 3 millionly. Diame ter= 60 000 Iy. Pleiades 03h 47.5m +24°07' 1.5 89' OC Taurus Also called"The Seven M 45 Sisters" and M45. Bright, open clusterwith 250 members. Six orseven stars easily visible tothe naked eye. Dis tance= 450 Iy. Diameter= 20 ly. Ring Nebula 18h 53.6m +33°02' 9.0 2.5' PN Lyra A very famous planetary M5 7 nebula with an extremely hot bluedwarf star in the center. Distanc e= 1400ly. Diameter= 0.5 Iy. Ring-Tail 12h 01.9m - 18°53' 13.0 3.2' Gal Corvus A very unusual pair of Galaxy interacting galaxies NGC 4038 resulting in extrao rdinarylong, curvedfilaments extendingfrom each galaxy. D istance= 90 million ly. D iameter= 100 000 Iy. Rosette 06h 30.3m +05°03' Neb Monoceros A diffuse nebula Nebula surrounding an open NGC 2244 cluster.Clouds ofdark interstellarmaterial against theglowing back ground of the nebulagive it its " rose" appearance. Dis tance = 2600ly. Diameter= 55 ly. Saturn Nebula 21h04.2m - 11°22' 8.0 1.7' PN Aquarius Planetarynebul awith an NGC 7009 elongatedring resembling the rings of Saturn. Distan ce= 4000 ly. Diamet er= 0.5 ly. Sculpto r OO h47.6m - 25°17' 7.1 25.1' Gal Sculp tor The bright estmemberof Galaxy the SculptorGalaxy NGC 2 53 Clusterand very similar in size to our Milky W ay. Total luminosityof 5 billion suns. Distance= 7.5 million Iy. D iameter= 70 00 ly. Siamese 12h 36.5m + 11°15' 11.3 3.0' Gal Virgo Elongate dgalaxy with Twins close companion galaxy. NGC4567 Sombrero 12h 40m - 11°37' 8.3 8.9' Gal Virgo Also calledM104. Galaxy Edge-ongalaxy with a M I04 darkband of interstellar Objects in the NexStar Hand Control 271
Name RA Dec Mag Size Type Const Com ments matterin theequatorial galacticplane resembling thebrimof asombrero. Distance=30 millionIy. Diameter=82 000 Iy. SpindleGalaxy lOh 05.2m -07°43' 9.2 8.3' Gal Sextans A greatly flattened, NGC 3115 ellipticalgalaxy shaped like aspindle. Distance=27 millionIy. Diameter=30000ly Stephan's 22h 36.1m +33°57' 12.7 2.2' Gal Pegasus A groupof five galaxies, Quintet some of which are NGC 7 317 connectedby " bridges" of interstellar matter. Sunflower 13h 15.8m +42°02' 8.6 12.3' Gal Canes An elongatedgalaxy with Galaxy Venatici a brightcoreanda tight M63 spiralpatternresembling a giantcelestialflower. Distance=35 millionIy. Diameter=90000 Iy. Swan Nebula 18h 20.8m -16°11' 6.0 46' Neb Sagittarius Diffuse nebula M17 resemblinga swan swimmingacrosswater. Distance=5500 Iy. Diameter= 151y. TarantulaNeb 05h 38.6m - 69°05' 8.2 40' Neb Dorado A giantdiffusenebula NG C 2070 located inthe Large M agellanic Cloud is the large stobjectof its kind knownin theUniverse. Distance= 1690001y. Diameter=800ly Trifid Nebula 18h 02.3m - 23°02' 6.3 29' Neb Sagittarius A diffuse nebula M20 characterizedby three darkbands dividingthe brightregionsof the nebula. Distance=3700ly, Veil Nebula 20h 56,4m +31°43' 2.5° SR C ygnu s A beautifulcomplex NG C 6992/ nebula,whose delicate 6960 filamentstructureis best seen usingan om filter. The Veil Nebulais the remnant of an ancient supernova thatexploded some 35000 years ago. Distance= 1500 Iy. Whirlpool 13h 29.9m +47°12' 8,4 11' Gal Canes Also called M51. One of Galaxy M51 Venatici the closestand brightest galaxie swith very pronouncedspiralarms. Distance=35 million Iy. Diameter= 100000 Iy. Wild Duck 18h51.1m -06°16' 5.8 14' OC Scutum Also calledMIl. A rich Cluster open clustercontaining Mil about 500 stars. Distance =6000 Iy. Diameter=211y. 272 The NexStar User's Guide
Asterisms
A collectionof unique starpatterns.
Name RA Dec Const Comments
Kite Cluster Ol h 40m +59°00' Cas A diamond-shapedpatternof stars resemblinga kitewith astringof 5 stars making up the tail. TriangleCluster 01h 54m +38°00' And A long stringof stars leadingto an isoscelestrianglesituatednear the bright,open cluster NGC 752. Perseus Cluster 03h 28m +49°00' Per Called the PerseusMoving Cluster, this asterismis a largeassociat ion of over 50starsscattered across 3° of the constellationPerseus.All stars visible are bright,very young, hot starsdatingback onlyabout 50 million years. Kemble's Cascade 03h 57m +63°00' Cam Long strandof 5th- to 8th-magnitudestars stretching over 2°.Continuingsoutheast from theclusterwill leadto the open cluster NGC1502. Little Fish 05h 18m +33°30' Aur Mor e thana dozen stars make up this clusterwhich cover an areaof 30' x 75' across Arrowhead Cluster 06h 40m -09°00' CMa A distinctive V-shapedpatternof star resemblingan arrowhead position sabout7°northof thestar Sirius. Number3 Cluster 06h 53m -10°12' CMa A patternof faint starsseen asa backwardsnumber" 3" througha low power eyepiece.Look for the bright,open cluster M50 just northwestof this asterism. Crown Cluster IOh 50m +56°12' UMa A small " crown" of starswith a bright"jewel" star nearthe center located 2°westof thestar Merak. Coma Star Cluster 12h 22m +25°48' CmB The Coma StarCluster.A V-shapedpatternof stars visibleto the naked eye.This clusteris one of theclosestto Earth at adistance of250 Iy. Star GateCluster 12h 36m -12°00' Crv A uniquetriangle of stars with anothertriangleof fainter starsin itscenter. Mini -Coathanger 16h 30m +80°12' UMi A patternof 10 faintstars spanning[ degree, nicknamedthe "Mini -coathanger" or "S" Cluster S Cluster 16h 37m +31°00' Her A curving patternof a dozenstars resemblinga backwards letter "S'. Ring Cluster 18h 04m +26°30' Her A faint ring ofstars witha brighter 7th-magnitudestarinside the ring. W Cluster 18h 35m +72°18' Dra An asteri smof 20 stars, with the 5 brighteststarsmakinga distinctive"w" pattern! degree across. Objects in the NexStar Hand Control 273
Name RA Dec Const Comments CoathangerCluster 19h 25m +20°12' Vul Called"Brocchi's cluster"or the "Coathangercluster". Visible to the naked eye 8°southof the star Albireo.Ten visible stars make up a coathangershapespanning 1°across. Spiral Cluster 20h 14m +36°30' Cyg A sprawlingpatternof stars resemblingthe arms of a spiral galaxy with abrighterreddishstar in the center. DiamondCluster 20h 39m +13°30' Del Seen as abrighttriangleof 7th-magnitude stars, with 6th-magnitudeThetaDelphini being thebrightest. HorseshoeCluster 21h 07m +47°18' Cyg A "horseshoe"patternof over a dozen 7th-to 11th-magnitude starsmeasuring20' across lying near thebrightstar Deneb. Number7 Cluster 23h 07m +59°00' Cas Nine 5th-and 6th-magnitude starsmakingup a sideways number"7". Arrow Cluster 23h 21m +62°30' Cas One degree of starsresemblingan arrowpatternnortheastof the cluster M52.
CCD Obiects
Only available in the NexStar 8/11 GPS and NexStar 5i/8i.A collection of galaxyclusterswell suitedto CCD imaging .
Name RA Dec Const Comments
NGC 383 Group Olh 07m 23' +32°25' Pisces Awell-populatedgalaxygroup with more than a dozen small galaxiesspreadover a 1.5°area. A good object for f/2 Fastar imaging. Arp 318 02h 09m 24' -10°08' Cetus Astringof four spiral galaxies arrangedin a line curving east and south. NGC 1068 & 1055 02h 42m 24' +00°13' Cetus This galaxy pairconsistsof a circularspiral galaxy with a brilliantcore and less brightspiral arms,with a visible dust lane runningthroughone of its arms. NGC 1097A 02 h 46m 12' -30°14' Fornax A stronglybarredspiral galaxy with a largebrightoval core. Detachedfrom the galaxy is a 30' companionoff thenorthern spiral bar. FornaxCluster 03h 22m 42' -3]012' Fornax This cluster iscenteredaroundits brightestmember,NGC 1316,a bright, slightlyelongatedoval galaxysurroundedby many fainter galaxies. 274 The NexStar User's Guide
Name RA Dec Const Comments
NGC 1400 & 1407 03h39m 59' - 18°35' Eridanus Two very similarspiralgalaxies with brightcores andfaint halos separatedby 12'. NGC 1532 & 1531 04h 12m 06' - 32°52' Eridanus This visually contrasti nggalaxy pair isseparatedby only 1.75'. NGC 1532 is a 10th-magnitude elongatedgalaxy witha bright core.NGC 1531 is a smalle r,less elongatedcompanion galaxy. NGC 1723 Group 04h59m 00' - 11°00' Eridan us A gro up of four galaxies in the shapeof a eat's paw with three faintgalaxiesin an arc and the brighter NGC1723,directlynorth of the trio. Bode's Galaxies 09hssm 36' +69 °20' This galaxy pair madeup of M81 and M82 arebothbright,oval galaxies separated by halfof a degree. Goodobjectfor Fastar f/2 imaging. NGC 3 158 Group IOh13m 48' + 38°46' This galaxy group centered around NGC 3 158 is madeup of eightgalaxies that spana 10' diameter and can be imaged at f/6.3 orat f/2 witha Fastar lens. NGC 3 190Group 10h18m 06' + 21°50' Leo NGC 3190 is the brightestmember of this trio of galaxies,which include NGC 3187 and NGC 3193. HydraI Cluster 10h36m 42' - 27°32' Hydr a Hydra I is a cluster of eight galaxiesthat lie at adistance of 200 million light-yearsaway.All are 11th- and 12th-magnitude galaxies.the farthestbeingabout 30' from each other.Good object for f/2 Fastar imaging. MI0 5 Trio IOh47m 48' + 12°35' Leo This galaxy groupis composedof an 8 arc minut etriangle of contrast inggalaxiesincludingan elliptical,lenticular and loose spiralgalaxy. ButterflyGalaxy IOh50m 00' +33°00' Two elongatedinteracting galaxies connectedat theirtips giving the appeara nceofa butterfly. Leo's Triple 11h19m 30' + 13°15' Leo The Leo Tripleis compr ised of two bright M essier objects(M65 and M66) and NGC 3628 that form a triangle ofmorethan 30' across. Best suitedfor Fastar f/2imaging. Copeland'sSeptet 11h37m 54' +2 1°59' Leo Copeland's Septet isa tight cluster of 6 faint galaxiesscatteredacross a 6' fieldof view.The galaxies range in brightnessfrom magnitude13.6 to IS. This cluster is best imaged through an f/6.3reducer. Ring-TailGalaxy 12hO l m 53' - 18°53' Corvus NGC 4038-39 is an unusual pair of interactinggalaxiesthat appearas one comma-shapedobject. Objects in the NexStar Hand Control 275
Name RA Dec Const Comments
h NGC 4298 & 4302 12 21m 43' +14°36' Coma This visuallycontrastingpair is Berenices onlyseparatedby I' andis best imaged at f/6.3 withreducerlens. Virgo Cluster 12h 26m 12' +12°57' Virgo M86 lies at thecenterof this galaxyclustersurroundedby sevensatellitegalaxiesof various sizes andmagnitude. Siamese Twins 12h 36m 36' +11°14' Virgo The Siamese Twins are a pair of interactinggalaxiesthatappearto bejoinedat the tips. NGC 5350 Group 13h 53m 24' +40°22' Canes This groupis positionedneara Venatici 6.5-magnitudestar and has a brightspiralgalaxy, NGC 5471 less than0.5°to thenortheast. A good object for f/2 Fastarimaging. NGC 5774-75 14h 54m 00' +03°33' Virgo Two spiralgalaxies,one seen edge-on,theotherseen face-on, with a faintcompaniongalaxy to thesouth. Stephan'sQuintet 22h 36m 07' +33°57' Pegasus These five galaxies all liewithina 3.5' areaandrange inbrightness from 12.6 to 13.6.Stephan's Quintetis positionedjustsouthof anothergood CCD object NGC 7330. Deer Lick Cluster 22h 37m 06' +34°25' Pegasus NGC 7331 is a nearly edge-on spiralgalaxy with foursmaller companiongalaxiesorbiting towards the east. Pegasus I Cluster 23h 20m 42' +08°13' Pegasus This galaxyclusteris made up of morethan10 faintgalaxies rangingin magnitudefrom II to 13. The clusterspans30' across with two equalbrightness twin galaxies in itscenter.Pegasus I is a good object for Fastar imaging. NGC 7782 Group 23h 53m 54' +07°58' Pisces At12th-magnitudeNGC 7782 is thebrightestof this five galaxy clusterlocatedin Pisces.
Stars
In additionto the Named, Double,andVariable star lists,additionalstarsare accessible using the Star buttonon thehandcontrol.The numberof starsvaries by NexStar model. Lists of thestarsare avail• ablein theDownloadssectionof my NexStarResourceSite - http://www.NexStarSite.com.
•NexStar 60/80/114/4- 2824stars.The new GThandcontrolorganizesthis list by SAO catalognumbers.The originalGT handcontrol uses aNexStar-specificnumberthatcan be cross-referencedto the SAOcatalogwith the list available on my web site. •NexStar 5/ 8- 10384starsorganizedby a NexStar-specificnumberthatcan becross-ref• erencedto the SAO catalog with the listavailable on my web site. 276 The NexStar User's Guide
• NexStar Si/8i and 8/11 GPS - 29522 stars organizedby SAO catalog numbers.
Messier Obiects
All 110 Messier objects areavailablein all NexStarmodels.The Messier objects arelistedin Chapter6 anda list is also available in theDownloadssectionof my NexStar Resource Site.
Caldwell Obiects
All 109 Caldwell objects are available in all NexStar models.A list of the Caldwell objects is available in theDownloadssectionof my NexStarResourceSite.
NGC Obiects
The NexStar 60/80/114/4handcontrolincludes1165 NGC objects.All othermodelsincludetheentire NGC catalog of 7840 objects.Both lists are available in theDownloadssection of my NexStarResource Site.
IC Obiects
The NexStar 5i/8i and 8/11 GPScontaintheentireIC catalogof 5386objects. A list of the ICobjectsis available in theDownloadssectionof my NexStar Resource Site.
Abell Obiects
The NexStar5i/8iand8/1 I GPScontainthe first 2712objectsin the Abell galaxyclustercatalog.The magnitudegiven by thehandcontrolis themagnitudeof thetenth-brightestgalaxy in thecluster.A list of these Abell objects is availablein theDownloadssectionof my NexStarResourceSite. Thereare a widevarietyof softwarepackagesavailablefor controllingyour NexStar telescope. Programswrittenfor Windows,Macintosh,andpalmtopcomputers(PDAs) can provideextended controlandenhancedfeaturesfor yourscope.Prices range from free to a fewhundreddollars.While manyof thepackagesare similarin function, someare quiteunique.I recommendyou spendsome timeresearchingat themanufacturers' web sites todeterminewhichsoftwarepackageor packages best suityourneeds. Table C.I shows thedesignationsusedto denotewhichmodelsof NexStarscopesare compatible with eachsoftware package. Followingis a list ofsoftwarepackagesavailableat thetimeof this writing; additionalsoftwareis introducedcontinually. Please visit the PC Control section of the NexStar Resource Site • http://www.NexStarSite.com- for the mostup-to-datelist. Allinformationis subjectto changeby the softwaremanufacturer; please visit theweb sitelistedfor the latest details.
Table C. 1. Designations denoting compatibilityof modelsof NexStarscopeswith software packages Model Description Original GT The originalGT (computerizedGoTo) handcontrol for the NexStar 60/80/114/4telescopes, as well as all Tasco StarGuidetelescopes. NewGT The upgradedGT handcontrolfor the NexStar 60/80/114/4 telescopes. This handcontrol is includedwith alllittle Ne xStars manufacturedafterDecember 2001 . See the sidebarOld versus New GT Hand Control in Chapter3 to determine whetheryou have the originalor new GT handcontrol. Ne xStar 5/8 The original NexStar5 and 8 models. These modelswerediscontinued in the summer of002 2 and replacedwith the NexStar5i and 8i. Ne xStar 5 i/8i The new NexStar5 i and 8i telescopes. Only the optionalcomputerized handcontrol allows PC control. Ne xStar GPS The NexStar 8/11 GPS telescopes.
277. 278 The NexStar User's Guide
NexStar Observer List
Author: MichaelSwanson Cost: Free Web Site:http ://www.NexStarSite.com / Computer systemssupported:Win dows 9s/98/ME/NT12000/XP Models ofNexStarsupported:Original GT, New GT, NexStar5/8,NexStar si/8i,NexStar GPS
Arrow Keys for GuideStar
Authors:M ichael Ganslmeierand MatthiasBopp Cost:Free Web Site:http://www.ddlus.de Computersystemssupported:Windows 2000/XP Mod els ofNexStarsupported:H C models (the manual handcontro l littleNexStars)and GT models with modifications Note: A unique package that allows thePC to act as the directionbutton s on thehand control.This allows completeremotecontrolof the littleNexStarsafterthe initial alignment isaccomplished.Visit the site and download the articleon "Co nt rolling theNexSta r4/60/80/114series telescopesfully remotely" forcomplete details.
ASCOM
Publisher: Astronomy Common ObjectModel(ASCOM) Cost: Free Web Site:http://ascom-standards.org Computersystemssupport ed:Windows 9s/98/ME/NT12000/XP Mod elsof NexStarsupported:OriginalG'I',New G'T , NexStar5/8,NexStar si/8i, NexStar GPS Note: This is a plug-in that isused byotherprogramsto controla telescope,not a standalone program.
AstroPlanner
Publisher:iLanga, Inc. Cost: $20 download version;$30 CD- ROM version WebSite:http://www.ilangainc.com/ astroplann er Computersystemssupported:Mac OS and Windows9s/98/ME/NT/2000/XP Models of NexStarsupported:OriginalGT, NewGT, NexStar5/8,NexStar si/8i,NexStar GPS
Cartes du Ciel (Sky Charts)
Author: PatrickChevalley Cost: Free Web Site:http://www.stargazing.net/astropc Computersystemssupported: Windows 9s/98/ME/NT/2000/XP Mod elsof NexStarsupported: Usesthe ASCOM pl ug-in above and supports the samescopes. Note that it is necessary to download theASCOM platform fromthe ASCOM lin k above andyou must downloadthe ASCOM driverfrom theCartesdu Ciel web site -the " CompletePackage" download does not include either. PC and Palmtop Software Compatible with NexStars 279 Deepsky 2003
Author:Steven Tuma Cost:$53 on CD, $40 whendownloaded Web Site:http://www.deepsky2000.net Computersystemssupported: Windows 95/98/ME/NT/2000/XP Models of NexStarsupported:Uses the ASCOM plug-inabove andsupportsthe same scopes.
Pocket Deepsky
Author:Steven Tuma Cost:$20 whenpurchasedseparately,free with apurchaseof Deepsky 2003 Web Site: http://www.deepsky2000.net Computersystemssupported:Windows CE Version 3 Models of NexStarsupported:NexStar5/8
Desktop Universe
Publisher:Main Sequence Software Cost:$300 Web Site:http://www.desktopuniverse.com Computersystemssupported:Windows 95/98/ME/NT/2000/XP Models of NexStarsupported: Uses the ASCOM plug-inabove andsupportsthe same scopes.
DigitalSky Voice
Publisher:Astro Physics, Inc. Cost: $175 Web Site: http://www.digitalskyvoice.com Computersystemssupported:Windows 95/98/ME/NT/2000/XP Models of NexStarsupported:New GT, NexStar5/8,NexStar5i/8i,NexStar GPS
Earth Centered Universe Pro
Publisher:Nova Astronomies Cost:$60 Web Site:http://www.nova-astro.com Computersystemssupported:Windows 3.1/95/98/ME/NT/2000/XP Models of NexStarsupported: Uses the ASCOMplug- in above andsupportsthe same scopes.
Guide CD-ROM Star Chart, Version 8
Publisher: Project Pluto Cost: $89 Web Site:http://www.projectpluto.com Computersystemssupported:DOS, Windows 3.1I95/98/ME/NT/2000/XP Models of NexStarsupported:Original GT, New GT,NexStar5/8,NexStar5i/8i,NexStar GPS 280 The NexStar User's Guide HNSKY
Author: Han Kleijn Cost: Free Web Site:http://www.hnsky.org Computersystemssupported:Window s95/98/ME/NT/2000/XP Models of NexStarsupported:Uses the ASCOM plug -in above and supportsthe same scopes.In addition to the ASCOM plug-in,you must also downloadthe HNSKY to AS COM Interfacefrom the HN SKY website.
MegaStar 5
Publisher: Willmann-Bell,Inc. Cost: $130 Web Site:http://www.willbell.com/software/megastar/index.htm Computersystemssupported:Windows 95/98/ME/NT/2000/XP Models ofNexStarsupported:New GT,NexStar5/8,NexStar5i/8i,NexStar GPS
NGCView
Publisher: Rainman Software Cost:$90 Web Site:http://www.rainman-soft.com Computersystemssupported:Windows 95/98/ME/NT/2000/XP Models ofNexStarsupported: Uses the ASCOM plug-inaboveand supports the samescopes.
Observer
Publisher: Procyon Systems Cost:$90 forIntermediate,$125for Advanced,Basicdoes notsupporttelescopecontrol Web Site:http://www.procyon-sys.com Computersystemssupported: Power Mac Models of NexStarsupported:New GT, NexStar5i/8i,NexStarGPS
Planetarium
Author:Andreas Hofer Cost:$24 Web Site:http://www.aho.ch/pilotplanets Computersystemssupported: Palm Pilot (orcompatible)runningPalm OSversion 2.0or higher Models of NexStarsupported: Original GT, New GT, NexStar 5/8,NexStar 5i/8i,NexStar GPS • requires download of telescopecontrolplug-in for specificscopes PC and Palmtop Software Compatible with NexStars 281
Real-Time PC Software for Astronomical Observers
Author: Robert Sheaffer Cost: Free Web Site:http://www.debunker.com/astro/rtastro.html Computersystemssupported: DOS,W indows 3.1/95/98/ME Models of NexStarsupported: Original GT,New GT, NexStar 5/8,NexStar5i/8i,NexStar GPS
Satellite Tracker
Author:Brent Boshart Cost:$20 Web Site:http://www.heavenscape.com Computersystemssupported:Window s95/98/ME/NT/2000/XP Models of NexStarsupported:NewGT, NexStar5/8,NexStar 5i/8i,NexStar GPS - continuous tracking on the NexStarGPS (HC 1.6 or higher)and NexStar5i/8i;leapfrog trackingon othermodels
SkyChart III
Publisher:Southern StarsSystems Cost:$50 Web Site:http://southernstars.com/skychart Computersystemssupported:Windows 95/98/ME/NT/2000/XPand Mac Models of NexStarsupported: NexStar 5/8and reportedly supports New GT, NexStar 5i/8i, and NexStar GPSwhen the Ultima 2000 driveris selected
SkyMap Pro
Publisher:SkyMap Software Cost: $100 Web Site:http://www.skymap.com Computersystemssupported:Windows 95/98/ME/NT/2000/XP Models of NexStarsupported: V ersion 7 supports the NexStar5/8;version 8 supportsNewGT, NexStar 5/8,NexStar 5i/8i,NexStar GPS
StarParty
Publisher: PFD Systems Cost:$12 Web Site:http://www.pfdsystems.com Computersystemssupported: Palm Pilot orcompatible -seeweb site for OSversionrequirements Models of NexStarsupported:Original GT, NewGT, NexStar 5/8,NexStar 5i/8i,NexStar GPS 282 The NexStar User's Guide
STAR Atlas:PRO
Publisher:SKYLab AstronomySoftware Cost:$130 Web Site:http://www.skylab.com.au Computersystemssupported:Windows 95/98/MEINT/2000/XP Models of NexStarsupported:Uses the ASCOM plug-inaboveand supportsthe samescopes
Starry Night Pro
Publisher:Space Software Cost:$180 Web Site:http://www.starrynight.com Computersystemssupported: Cur rent version (version4) only supports Windows 98/ME12000/XP and Mac OS X 10.1or higher.Version 3 supportsWindows 95/98/ME/NT/2000/XPand olderMac OS versions. Models of NexStarsupported: Windows version - can use the ASCOMplug-in for controllingmodelslistedin the ASCOM section above.M ac version - Various plug-insareavailablesupportingNew GT, NexStar5/8,NexStar 5i/8i, NexStar GPS
TheSky Level II or Higher
Publisher:Software Bisque Cost: LevelII - $130 Web Site:http://www.bisque.com Computersystemssupported:Windows95/98/ME/NT/2000/XPand Mac Models of NexStarsupported:New GT,NexStar5/8,NexStar5i/8i,NexStar GPS
TheSky Pocket Edition
Publisher:Software Bisque Cost:$50 Web Site:http://www.bisque.com Computersystemssupported:Windows CE V ersion3 on Pocket PC, Windows CE 2.11for Palm-size PC and a fewotherversion/hardwarecombinations detailedon the web site. Models of NexStarsupported:New GT, NexStar5/8,NexStar 5i/8i,NexStarGPS
Voyager III with SkyPiiot
Publisher: CarinaSoftware Cost:$200 (be certainto purchaseSkyPilot,sold separately) Web Site:http://www.carinasoft.com Computersystemssupported:Windows 98/ME/2000/XP Models of NexStarsupported:NexStar5/8,NexStar GPS, NewGT, NexStar5i/8i In additionto theinformationpresentedhere, severalresourcesare available at the NexStar Resource Site(http://www.NexStarSite.com)toincludesampleprogramswritteninVisuaIBasic6.awidelyused programmingplatform.The completesource code for theseprogramsis available fordownloadfrom the NexStarResourceSite. Thesourcecode requiresthatyou have Visual Basicinstalledon your computer.
Basic Control Commands - Get .. J ....,. '. .. '. ..',' .;
For manyprograms,these are the onlycommandsthat will be necessary. The GoTocommandsdirect the telescopeto slew to thecoordinatesprovided.The Getcommandsquerythe telescopefor the currentcoordinatesof thepositionthetelescopeis pointed.There arecommandsfor bothRA-Dec and Alt-azcoordinates. Thecommunications parameterfor all models is 9600bits per second, no parity, no stop bit, and no flow control. This last parametercauses manyproblems,be sure you do not select Xon!Xoff (sometimescalled software flowcontrol)or Hardwareflow control. As describedin Chapter10, various models of NexStar telescopes have beenintroducedwith differ• ing commandsets. The following sectionsdiscuss the commandsfor each of thethreedistinct protocolsexistingin the NexStar line.
NexStar 5/8 Golo RA-Dec • pcsendsbinaryvalue 63 (ASCII"?") . • The telescope replies withbinaryvalue 35 (ASCII "#") . • PCsendsbinaryvalue 82 (ASCII "R") followed by the RAhigh-byte,RA low-byte,Dec high-byte, Dec low-byte. • The telescope slews to the RA-Deccoordinates- aftercompletionthe telescope replies withbinary value 64 (ASCII "@").
283 284 The NexStar User's Guide
Get RA-Dec • PCsendsbinaryvalue 63 (ASCII "?"). • Thetelescopereplies withbinaryvalue 35 (ASCII "#") . • PC sendsbinaryvalue 69 (ASCII "E") . • Thetelescopereplies with the RAhigh-byte, RA low-byte, Dec high-byte,Dec low-byte.
Gala Alt-az • PC sendsbinaryvalue 63(ASCII "?"). • Thetelescopereplies withbinaryvalue 35 (ASCII "#") . • PCsendsbinaryvalue 65 (ASCII "A") followed by the Azmhigh-byte,Azm low-byte, Althigh-byte, Alt low-byte. • Thetelescopeslews to theAlt-azcoordinates- aftercompletionthetelescopereplies with binary value 64 (ASCII "@").
Get Alt-az • PC sendsbinaryvalue 63 (ASCII"?"). • Thetelescopereplies withbinaryvalue 35 (ASCII "#") . • PC sendsbinaryvalue 90 (ASCII "Z"). • Thetelescopereplies with the Azmhigh-byte,Azm low-byte, Althigh-byte,Alt low-byte.
Note thatthe high-byteandlow-bytevalues for thesecommandsare binaryvaluesformattedas individualASCII characters. For example,to senda GoTo commandwith RA high-byte124andlow• byte 54andDec high-byte15 and low-byte 32,thecorrectVisual Basic stringwould be: "R" & Chr(124) & Chr(54) & Chr(15) & Chr(32)
To calculatethehigh-byte,divide theencodervalue by 256 andconvertto aninteger(dropthe frac• tionalpart). To calculatethe low-byte,divide the encodervalue by 256and use the remainder (modulusoperationor thefractionalpartmultipliedby 256). Forprogrammingexamplesandother details,refer to the NexStarResourceSite.
Original GT Gala RA-Dec • PC sendsbinaryvalue 82 (ASCII " R") followed by the RAhigh-byte,RA low-byte,binaryvalue 0, Dec high-byte,Dec low-byte,binaryvalue O. • Thetelescopeslewsto the RA-Deccoordinates.
Get RA-Dec • PC sendsbinaryvalue 69 (ASCII "E "). • Thetelescopereplies with the RAhigh-byte, RA low-byte,binaryvalue 0, Dec high-byte,Dec low• byte,binaryvalueo. Writing Programs to Control NexStar Telescopes 285
Golo Alt-az • PC sends binaryvalue65 (ASCII"A") followed by the Azm high-byte,Azm low-byte,binaryvalue 0, Alt high-byte, Altlow-byte, binaryvalue o. • The telescope slews to the Alt-azcoordinates.
Get Alt-az • PC sends binaryvalue90 (ASCII " Z"). • The telescope replies with the Azm high-byte,Azm low-byte,binaryvalue 0,Alt high-byte,Alt low• byte,binaryvalueo.
Note thatthehigh-byte andlow-bytevaluesfor these commandsare binaryvaluesformatted as individualASCII characters.For example, to send a GoTocommand with RA high -byte124 and low• byte 54 and Dec high-byte15 and low-byte 32, thecorrectVisual Basic string would be: " R" & Chr(124) & Chr(54) & Chr(O) & Chr (15) & Chr(32) & Chr(O)
To calculatethehigh-byte, dividetheencodervalueby 256 and converttoan integer(drop the frac• tional part). To calculate the low-byte, dividethe encoder value by 256 and use theremainder (modulus operationor thefractionalpartmultiplied by 256).For programmingexamplesand other details, refer to the NexStar ResourceSite.
NexStar 8/11 GPS, NexStar 5i/8i, New GT Golo RA-Dec • PC sendsbinaryvalue 82 (ASCII "R") followed by the RA high -byte,RA low-byte,binaryvalue 44 (ASCII" ."),Dec high-byte,Declow-byte. • The telescopeslews to theRA-Dec coordinates.
Get RA-Dec • PC sends binaryvalue 69 (ASCII " E"). • The telescope replieswith the RAhigh-byte,RA low-byte,binaryvalue 44 (ASCII "." ), Dec high• byte,Dec low-byte.
Golo Alt-az • PC sends binaryvalue66 (ASCII " B") followed by theAzm high-byte,Azmlow-byte,binaryvalue 44 (ASCII "," ),Alt high-byte, Alt low-byte. • The telescope slewsto the Alt-azcoordinates.
Get Alt-az • PC sends binaryvalue 90 (ASCII "Z "). • The telescopereplies withthe Azmhigh-byte, Azmlow-byte,binaryvalue 44 (ASC II","), Alt high• byte, Altlow-byte. 286 The NexStar User's Guide
Note thatthehigh-byteandlow-bytevalues for thesecommandsarebinaryvaluesformattedas two-digit hexadecimalnumberssent as ASCIIcharacters.For example, to send a GoTocommandwith RA high-byte124 and low-byte54 and Dechigh-byte15 and low-byte 32, thecorrectVisual Basic string would be:
"R" & Mid("OO", L 2 - Len(Hex(124))) & Hex (124) & Mid("OO", 1, 2 - Len(Hex(54))) & Hex(54) & "," & Mid("OO", 1, 2 - Len(Hex(15))) & Hex(15) & Mid("OO", 1, 2 - Len(Hex(32))) & Hex(32)
To calculate the high-byte, divideencoder the value by 256 and convert to an integer (drop the frac• tionalpart).To calculatethe low-byte,divide theencodervalue by 256and use theremainder (modulusoperationor thefractionalpartmultipliedby 256).For programmingexamples andother details, refer to the NexStar Resource Site.
A v. n ommands . .
Additionalcommandshave beenintroducedfor some of the NexStar models. The modelsapplicable are notedfor each of thecommandsbelow. Notethataftermanyof thesecommandsthe telescope sends one extra bytebinary - value 35 (ASCII "#") - to indicate thecommandhas completed.
Get Hand Control Version
(NewGT, NexStar8/11GPS, NexStar5i18i)
Returnshandcontrolversion only.Two bytesreturned.Each byte is a single-bytebinarynumberthat shouldbe convertedto decimal.For example,in Visual Basic, use the ASCfunctionto convertthe binaryvalue to decimal. The first byte is the whole-numberversion; thesecondbyte is thefractional part. For example, if the valuesreturnedare 1 and 6,thehandcontrolis version 1.6. • PC sendsbinaryvalue 86 (ASCII"V"). • The telescope replies with thewhole-number-versionbyte and thefractional-number-versionbyte.
Cancel GoTo
(NexStar 8/11GPS, NexStar5i18i)
Used to cancel a GoTo slewmid-progress.
• PC sendsbinaryvalue 77 (ASCII"M") .
Is GoTo in Progress
(NexStar 8111 GPS, NexStar5i!8i)
Used todetermineif a GoTo iscurrentlyin progress. Returns a single-bytebinarynumberthat should be convertedto decimal.For example,in Visual Basic, use the ASCfunctionto convertthebinary value to decimal. Writing Programs to Control NexStar Telescopes 28
• PC sendsbinaryvalue 76 (ASCII"L"). • Thetelescopereplieswith asingle-bytebinaryvalue. If the value is 49 (ASCII"I "), a GoTo is in progress.Ifthe value is 48 (ASCII"0"), no GoTo is inprogress.
Is Alignment Complete
(NexStar 8/11 GPS, NexStar 5i18i)
Used todetermineif the staralignmenthas been completed.The GoTo/Get RA-Deccommandsdo not functionpriorto alignment. Returns a single-bytebinarynumberthat should beconvertedto decimal. For example, in Visual Basic, use the ASCfunction to convertbinary the value to decimal.
• PC sends binaryvalue 74 (ASCII "1"). • The telescope replies withsingle-byte a binaryvalue.Ifthe value is I,alignmentis complete.If the value is0,alignmenthas not beencompleted.
Tracking Mode (Start/Stop Tracking)
(NexStar 8/11 GPS hand controlversion 1.6 or higher, NexStar 5i18i)
The TrackingMode commandprovidesthe samecapabilityas the same functionfound on the Menu buttonof thehandcontrol.It is required via computercontrolwhen using the nextcommand, Tracking Rate.Prior tosendinga trackingrate change, you mustuse Tracking Mode to stop(turnoff) tracking.To resumenormalsiderealtrackingyou mustuse theTrackingMode commandto resume tracking.To resumetracking,you must choice one ofthreetrackingmodes:Alt-az,EO North, or EO South. Alt-az is the trackingmode used when the scopemounted is directlyon the tripod. EO North/Southare used when thetelescopeis polar-alignedon a wedge(Northernor Southern Hemisphere).Unfortunately,thereis no commandto determinethe currenttrackingmode,so a programthat will use the Tracking Modecommandmust ask the user to select thecorrectmode. • PC sendsbinaryvalue 84 (ASCII " T") and asingle-bytebinaryvalue to set thetrackingmodeas follows: o- stoptracking I - start Alt-az tracking 2 - startEO North tracking 3 - start EO Southtracking.
Tracking Rate
(NexStar 8111 GPS hand controlversion 1.6 or higher, NexStar 5i18i)
The TrackingRatecommanddirects the telescope to begin slewing left, right, up, or down - the same directionsavailable to thearrowbuttonson thehandcontrol.Providingyou first stoptrackingusing the Tracking Modecommand,the telescope willcontinuemoving at therequestedrate until you issue eitheranotherTrackingRatecommandor anotherTrackingMode command.For example, you can 288 The NexStar User's Guide issue aTrackingMode commandto stoptracking,then a Tracking Ratecommandto slew up at0 1per second,and then after anyamountof time, you can issueTracking a Mode commandto startAlt-az trackingandthetelescopewill resumenormaltrackingatsiderealrate. Thismethodcan be used to writeprogramsthat provideon-screenbuttonsto emulate the arrowbuttonson thehandcontrol. Also note that you can start one axis tracking at any given rate and then startother theaxis tracking at anindependentrate.This allows trackingof objects,like satellites,moving on a predetermined course across the sky. Following are the fourvariationsof theTrackingRatecommandto allowmovementin any of the four directions.Each commandrequires 8 bytes; each byte shown is a decimalbinaryvalue. PositiveAzimuthTracking(move right) 80, 3, 16,6, TrackRateHigh, TrackRateLow, 0, 0
Negative AzimuthTracking(move left) 80,3, 16,7,TrackRateHigh,TrackRateLow, 0, 0
PositiveAltitudeTracking(move up) 80,3,17,6,TrackRateHigh, TrackRateLow, 0, 0
NegativeAltitudeTracking(move down) 80,3,17,7,TrackRateHigh, TrackRateLow, 0, 0
Multiply your desiredtrackingrate,expressedin arc secondspersecond,by a factorof 4. For example,10 per secondis 3600 arcsecondsper second.Multipliedby four, thisresultsin a tracking rate of 14400.To calculateTrackRateHigh,divide this value by 256 andconvertto aninteger(drop the fractionalpart).To calculateTrackRateLow,divide the encodervalueby 256 and use the remainder(modulusoperationor the fractionalpartmultipliedby 256).A sampleprogramusing thesecommandsto emulatethehandcontrolbuttonsis availablefor downloadfrom theNexStar ResourceSite.
32-bit RA-Dec Get and GoTo
(NexStar8111 GPS hand controlversion1.6or higher, NexStar5i18i)
GoTo RA-Dec
• PCsendsbinaryvalue 114 (ASCII "r") followed by the RAhigh-byte,RA mid-byte,RA low-byte, binaryvalue 0,binaryvalue 44 (ASCII ","), Dec high-byte,Dec mid-byte, Dec low-byte,binary valueo. • The telescope slews to the RA-Deccoordinates.
Get RA-Dec
• PC sendsbinaryvalue 101 (ASCII"en). • The telescope replies with the RAhigh-byte, RA mid-byte,RAlow-byte,binaryvalue 0,binaryvalue 44 (ASCII","), Dec high-byte, Dec mid-byte,Declow-byte,binaryvalueO.
Notethatthehigh-byte,mid-byte,and low-byte values for thesecommandsarebinaryvalues for• mattedas two-digit hexadecimalnumberssentas ASCII characters.For example,to send a GoTo Writing Programs to Control NexStar Telescopes 289
commandwith RA high-byte124, mid-byte30,low-byte 54 and Dechigh-byte15, mid-byte102,low• byte 32, thecorrectVisual Basic string would be:
" x" & Mid(" OO", 1, 2 - Len(Hex(124))) & Hex(124) & Mid("OO" , 1, 2 - Len(Hex(30))) & Hex(30) & Mid("OO", 1, 2 - Len(Hex(54))) & Hex(54) & "00," & Mid("OO", 1, 2 - Len(Hex(15))) & Hex(15) & Mid("OO ", 1, 2 - Len(Hex(102))) & Hex(l02) & Mid("OO" , 1, 2 - Len(Hex(32))) & Hex(32) & "00"
To calculatethehigh-byte,divide theencodervalue by 65 536 andconvertto aninteger(dropthe fractionalpart).To calculatethemid-byte,multiplythehigh-byteby 65 536 andsubtractit from the encodervalue, then dividethe answer by 256 and convert to an integer.To calculate the low-byte, mul• tiply the high-byteby 65536,multiplythemid-byteby 256,and subtractboth from theencodervalue; the answer is thelow-byte.For programmingexamplesand otherdetails,refer to the NexStar Resource Site.
Additional Commands ..
Andre Paquettehas investigatedtheinternalcommunicationsprotocolof the NexStar8111 GPS and NexStar 5i/8itelescopes. Some of themoreuseful commandscontrolthe motorcontroland GPS modules.He has publishedan excellent guideto thesecommandsfor thetechnicallyinclined,which you will find available at hisweb sitehttp://www.paquettefamily.ca/nexstar/ Appropriatecaremustbe used withany of theseadditionalcommandssince a few of them can renderyour telescopeinoperable,requiringa returntrip to Celestron (most likely at your expense!) to remedy thesituation. AFOVSee apparentfield of view. Airy disk The image of a star as seenthrougha telescope.Although a star is apinpointof light, due to theinteractionof light and optics,appears it as a very small disksurroundedby one or more faint dif• fraction rings.Viewing the Airy diskrequiresgood optics,steady seeing, and a well-collimated scope. alt-azimuthor altitude-azimuthA methodof mountinga telescopeso thatmotionis allowed left to right (azimuth)and up and down(altitude). apparentfieldofview(AFOV)The apparentangularslice shown by an eyepiece.A larger AFOVyields a "wider" view, while anarrowAFOV is oftenlikenedto viewingthrougha drinkingstraw.See also field of view andtruefield of view. apertureThe diameterof a telescope'sobjective(mainlens or mirror). Larger aperturesprovide greaterlight-gatheringpower (the ability to show fainter objects) and higherresolution(the ability to show finer detail). arc minuteA unit(symbol ') used tomeasuretheangularseparationof objectsin the sky.An arc minuteis;oof a degree. arc secondA unit(symbol'") used tomeasuretheangularseparationof objectsin the sky.An arc secondisloof an arcminute. asterismA recognizablepatternof stars, for example the BigDipper or theSouthernCross. asteroidA small rocky bodyorbitingthe Sun orotherstar. In our solar system, greatconcentrationsof asteroidsare found in orbit between Mars and Jupiter. avertedvision A techniqueused to see faint objects.Bylooking to the side of the object,the faint light falls on the more sensitive part of the eye. binarystarSee doublestar. binocularviewers Often simply called "bino viewers", used with a telescope, this specialadapterallows viewing with both eyes. Caldwellcatalog109 deep skyobjectsto expandbeyondthe Messier list. Many of theseobjectsare only visible to observers in theSouthernHemisphere.See also Messier catalog. catadioptrictelescope A telescope design using both mirror and lenses, for example, Schmidt-Cassegrainor Maksutov-Cassegraintelescopes. celestialequatorAn imaginaryline on the sky found directly above theEarth'sequator.Objectsnorth of the celestialequatorhave a positivedeclination;objects south have a negativedeclination.
291 292 The NexStar User's Guide celestial pole Either of the points in thesky directly above theEarth'sNorth or South Pole. collimationAlignment of the optical elementsof a telescope,binocular,or otheroptical device. cometA celestial body, made mostly of ice and rock, usuallyorbitinga star in a highly elliptical orbit. compoundtelescopeAnothername,andeasierto pronouncethancatadioptric,for atelescope designusing bothmirrorand lenses.Schmidt-Cassegrainor Maksutov-Cassegraintelescopesare examples. correctorplateThe large lenson thefrontof Schmidt-Cassegrainor Maksutov-Cassegraintele• scopes.The correctoron aMaksutov-Cassegrainis also called the meniscus lens. crescentMoon A lunar phase area when less thanquarter a of the surface of the Moon visible from the Earth isilluminated. DECSee declination. declinationA measurement,in degrees,of an object'sangulardistancefrom thecelestialequator. Objectsnorthof the celestialequatorhave a positive declination; objects south of the celestialequator have anegativedeclination. Used togetherwith rightascension,providesthepreciselocationof an object in the sky. deepsky objectObjectsoutsideof oursolarsystemare known collectivelyas deep skyobjectsor DSOs . DSOs rangefrom individualstarsto cities ofstarsknown as galaxies. Refer toChapter2 for more details. degreeA unit(symbol 0) used tomeasuretheangularseparationof objects in the sky.There are 3600 measuredarounda complete circle. doublestarA star that can be resolved with optical aid to show two stars.Multiple stars are also found with threeor moremembers. Some arebinary/multiplesystemswith thememberstarsrevolving arounda commoncenterof gravity.Others are merely an optical effect withmemberstarsseparated by greatdistancesbutcoincidentallyin acommonline of sight as viewed from the Earth. DSOSee deep sky object. eclipticThe line in the skythattheplanets,the Moon, and the Sun travel along. The line resembles a sine wave 23° above thecelestialequatorat its highpoint,23° below thecelestialequatorat its low point.The courseandseasonalorientationof the line is due to the0 23tilt of theEarth'saxis and the Earth'spatharoundthe Sun. ep or e.p. Sometimes used asabbreviation an for eyepiece. equatorialmountA methodof mountinga telescope so that one of the axes (called theascension right axis) is alignedwith the Earth'saxis. Theotheraxis (called thedeclinationaxis) is mountedat a 900 angle to the first. This allows easytrackingof the sky as theEarth rotateson its axis.The most commonarefork-mountedscopes on a wedge or the German Equatorial Mount (GEM) exitpupilThe size,in millimeters,of the column of light projectingfrom the eyepiece of a telescope or binoculars.Refer toChapter2 foradditionaldetails. fieldofview(FOV) The view in the eyepiece oftelescope a or binoculars.Typical usage: "The Orion Nebula filled the entire field of view."Refer toChapters2 and 8 for more details. focal lengthTraditionally,the measureddistancefrom the mainobjective (lens ormirror)of an opticalinstrument,to the point where the imagebrought is to a focus. Forcompoundtelescopes such as Schmidt-Cassegrainand Maksutov-Cassegrain,the complex curves of thecorrectorand mirrors fold and compress the light path so that a relativelyshortoptical tube projects a longer effective focal length. focalratioThe result ofdividingthe focallengthof a telescopeby itsaperture.Focal ratio iswritten "finumber". For example,the NexStar 80 has a focallengthof 400 mm and anapertureof 80 mm resultingin a focal ratiooff/5(400/80= 5). focalreducerAn opticaladapterthat effectively decreases the focallengthof a telescope.Sometimes called atelecompressoror reducer/corrector. FOV See field of view. Glossary 293
full Moon The phase of theMoon when theentireilluminatedportionof the Moon is facingthe Earth. galaxyA grouping of hundreds of millions or even billions of starsboundtogetherby gravityand travelingtogetherthroughspace. Thereare billions of galaxiesin the universe. GEMSee equatorialmount. gibbousMoon A lunarphasearea whenmorethanhalfof thesurfaceof the Moon visiblefrom the Earth isilluminated. globularclusterA group ofhundredsof thousandsof starsboundtogetherby gravity. IC catalog5386objectscatalogedby J.L. E. Dreyer.In addition toindividualand doublestars,the majorityof DSOsof interestto amateurastronomersare found in this or the NGCcatalog. localsiderealtime The hour,minute,and second ofrightascensiondirectly overhead at anyinstant. magnitudeA measurementof thebrightnessof acelestialobjectas viewed from any givenlocation (suchas theEarth).Smallernumbersindicatebrighterobjects,with negativenumbersbeingthe brightest.Refer toChapter2 for more details. Maksutov-CassegraintelescopeSometimescalled Maksutov or simply Mak, a telescope design using mirrorsand a deeply curvedcorrectorplate to create a compactinstrumentwith a relatively long focal length. For a more detaileddescription and figure, refer to Chapter 2. meniscuslens Also calledcorrectorplate,the large lens on thefront of Maksutov-Cassegrain telescopes. meridianAn imaginaryline drawn from duesouth,directly overhead, and then duenorth. Messier catalog110 DSOs of varioustypes of objects.Most of thebrighterdeep skyobjectsvisible in theNorthernHemisphereare listed in Charles Messier'scatalog.Generally these objects are the first DSO targets forbeginningamateurastronomers.Messier I would becommonlyreferredto as"MI" . meteorA small particle that entersthe Earth'satmosphere,burningaway witha streakof light. meteoriteA small metal or rockyobjectthatenterstheEarth'satmosphereand reachesthesurface beforebeing completelyconsumedby the heat. nebulaA huge cloud of dustand/orgas found in space.Refer toChapter2 for more details. new Moon The phaseof the Moon when theentireilluminatedportionof the Moon is facing away from the Earth. Thus, the unlit side of the Moon faces us. NewtonianreflectortelescopeA telescope designusing a largeconcavemirrorand a small flatmirror to gatherand focus light.For a more detaileddescription and figure, refer toChapter2. NGC catalog7840 objects catalogedby J.L. E.Dreyer. Inadditionto individual anddoublestars,the majorityof DSOsof interestto amateurastronomersare foundin this or the IC catalog. openclusterA group oflessthan a fewhundredstars looselyboundby theirmutualgravity.Most are slowly driftingapartand are relatively young. parfocalA characteristicof two ormoreeyepiecesthatallows themto beexchanged in atelescope with little or no refocusingrequir ed. RICreducer/corrector.Seefocalreducer. RASee rightascension. reducer/correctorSee focalreducer. reflectortelescopeA telescopedesignthatutilizesa mirrorfor the mainopticalcomponent.See Newtonianreflector,Schmidt-Cassegrain,and Maksutov-Cassegrainfor examples. refractortelescope The oldesttelescope design,refractor a uses a lens forthe main opticalcomponent. For a more detaileddescription and figure, refer toChapter2. resolution Smallest detail able to bedetectedin an optical device.Usuallymeasuredin arcseconds. rightascensionLines drawn against thesky runningfrom the north celestial pole to the south celestial pole. AbbreviatedRA. Right ascensionchanges as we move"east" and" west" in the sky. Right 294 The NexStar User's Guide ascensionis measuredin hours,minutes,and seconds.The entiresky is dividedinto 24hours,each houris dividedinto60 minutes,and eachminuteis dividedinto60 seconds.Used togetherwith declination,provides the preciselocationof an object in the sky. RS-232A communicationsstandardin thecomputerindustry.The port on thebottomof the NexStar handcontrolis RS-232-compatible. Thecomputerindustryis replacing RS-232with newerstandards such as USB.SeeChapter10 for more details. Schmidt-Cassegraintelescope(SCT) A telescopedesign usingmirrorsand a relatively flatcorrector plateto createa compactinstrumentwith a long focallength.For a moredetaileddescriptionand figure, refer toChapter2. SCT See Schmidt-Cassegraintelescope. seeingconditionsThe overallqualityof the localatmosphereas it affects celestialobservations.The threemain factors affecting seeingconditionsare known astransparency,seeing. and lightpollution. Transparencyis affectedby particlesin the air such asmoisture,dust,pollution,etc.Seeing is the effect ofunsteadyair - basically airturbulence.Light pollutionis caused by theenormousamountof light civilizationsends into thenightsky. Thebrightnessof the Moon has asimilaraffect. For more details, refer toChapter2. serialportA name commonlyused for an RS-232port oncomputer a .SeeChapter10 for more details. siderealrate The rate at which the stars move across the sky.Each star takes a little less than 24 hours to make a complete circuitaroundthe sky. slew Technically, anymovementof a telescope upon itsmount,but morecommonlyused toindicate moving a scope with themotorson themount. terminatorThe linedividingthelightedand darkhalves of aplanetarybody. Generallyconsidered most importantwith the Moon sincelunarfeatures are moststrikingalong theterminator. TFOV See truefield of view. transparencySee seeingconditions. truefield of view (TFOV) Theactualangulardistanceacross the field of view in an eyepiece.In any given telescope, the true field of view changes as you use various eyepieces.Refer toChapters2 and 8 for more details. USB- Universal Serial Bus Themodernreplacementfor the RS-232serial port. All newcomputersare equippedwith USB portsand manyno longercome with an RS-232port.Since theinterfaceon NexStar telescopesis RS-232, some newercomputerswill requirea "USB to serial" adapter.See Chapter10 for more details. variablestarA star thatchangesmagnitude(brightness)by ameasurabledegree. Some are caused by unstablenuclearreactions. Othersare actuallybinaryor doublestarsystemsresultingin lesser magnitudewith both stars aligned with our line of sight. vignetteDarkeningaroundthe edges of the field of view,usually most noticeableastrophotographs in . Generally this is caused by using anequipmentcombinationthat exceeds the maximum possible field of view for a telescope. visual back The l.2S-inch or 2-inch adapter on the back of aSchmidt-Cassegrainor Maksutov-Cassegraintelescope. Typically a diagonal is placedinto the visual back to allow comfortableviewing. waningMoon Any phase of the Moon after the full Moon andpriorto the new Moon.Thus the Moon is "shrinking" in phase each night. waxing Moon Any phase of the Moon after the new Moon andpriorto the full Moon.Thus the Moon is "growing" in phase each night. wedge Anadapterplaced between thetripodand afork-mountedtelescope to allow polar alignment. zenithThe pointdirectly overhead. Index
alignment -mirrors216 GoTo -Alignment Myths 84 - objectivelenses 216 - object 87 - centeringalignmentstars72 -opticalsurfaces215 - specifiedRA-Dec 91 - common problems78 CN-16GPS module 59 GoTo approach95,100 - "M ust Do's" 70 coldweather 167 GoTo telescope, definition2 - overview 69 collimation GPSalign misses alignmentstars -Re-Alignment 83, 257 -aids 176 248 - star selection74 -description175 GPS hand control versions 64 -wedge alignment 81 -M aksutov(NexStar4) 183 GPS link problems 249 alignment methods -Newtonian (NexStar114) 178 GPS modulebattery242 -Auto Alignment76 - refractor (NexStar60/80) 184 GPS module, CN-16 59 -EQ North/South Alignment80 -SCT (NexStar 5 and Larger) 176 GT hand control, new 49 -GPS Alignment74 comets24 GT hand control,old 49 - Quick Alignment79 compasscalibration 94 -Two StarAlignment78 computercontrolSee PCcontrol altitude-azimuth mount40 constellation9 hand control alt-sensor calibration 94 cool down time15 -alterna telocations241 angularseparation12 corrector plate37 -compatibility betweenmodels anti-backlash92 counterweights 168 247 asteroids23 covers164 - GPSseries64 astronomy clubs118 -GT series49 astrophotography _ "inseries64 - adapters 204 dark adaptation 15 - incorrecttime 247 -autoguiders202 declination 11 - Messier objecterrors250 -books193 deep sky objects26, II I -misbehaving 248 -camera mounts 169,197 dewprevention 165 -originalGT bugs 256 -cameras 194 dew shield166 hand controlfeatures - digital image processing201 dew strip,electric 167 -Abellcatalog91 - Fastar 203 diagonals 157 -A nti-Backlash92 - focusing199 digital cameras194,20I - Asterisms 90 - image gallery208 doublestars27,112 -A utoguideRate99 - web sites 193 DSO See deep skyobjects -Caldwellcatalog88 autoguiders202 Dunlop100list 118 - CCD Objects90 avertedvision 15 -CordwrapPrevention97 -Direction Buttons 100 electronics, care230 -Filter Limits93 BaaderBracket 237 equatorial mount41 -GetAlt-Az 101 backlash 92 exitpupil 32 -GetRA-Dec 91 Barlowlenses156 extension cables, handcontrol170 -GoTo Alt-Az 101 binocularviewers156 eye relief 32 - GoTo Approach 95,100 binoculars 33 eyepieces 43, 152,154 - GoTo RA-D ec91 buying aused NexStar 239 - Hibernate 100 -IC catalog91 Fastar 203 -Info 88 Caldwelllist 112 filter limits 93 -LightControl 97 camera mounts 169,197 filters 160 - Messier catalog88 cases164,165 finder scopes 39, 163 -NamedObjects90 CCDastronomy cameras196, 202 focallength 31 -Named,Double,and Variable CGEseries telescopes 65 focalratio 31 Stars89 chairs 169 focalreducer/corrector156,205 -NGCcatalog89 cleaning focuser,improving sensitivity245 - PeriodicError Correction98 - corrector plates 216 - Reset toFactorySettings102 - diagonals218 - RS-232Mode 95 -exteriorsurfaces218 galaxies 29 -SAO catalog 89 -eyepieces217 globularclusters27 - Select Model101
295 296 The NexStar User's Guide
-Setup Time-Site96 NexStar 114 54 SCT SeeSchmidt-Cassegrain -SlewLimits 93 NexStar452 telescopes -Tour90 NexStar 4 rear port254 SCTrear port 243 - Tracking Mode and Rate99 NexStar556 seeing conditions 14 - User DefinedObjects96 NexStar 5i 58 sessionplanningsoftware 107 -Version102 NexStar 8 56 siderealrate12 - View Time-Site96 NexStar 8i 58 slew limits93 Herschel400 list 112 NexStar 8 GPS61 slewrate88 hibernate100 NexStar11GPS 61 software NexStar 50 Club119 - planetarium 106 NexStar ObserverList -session planning107 "i" series hand control versions 64 -alignmentstar chart 137 - specialized 107 image shift, focusing 245 -configuration132 solar filters161 Info, hand controlfeature 88 - database 131 solarsystem objects17, 108 - description 131 speed of light 26 - download 5,139 star charts105 Jupiter 23,110 -HyperHand Controller133 stars 27 - installation 132 Sun 17,109 - observer lists132,135 supernova remnants29 latitude, accuracyfor alignment - printing137 surface brightness13 85 - using with your telescope138 latitude,enteringon handcontrol No Response16/17 errors249 77 NSOL SeeNexStar ObserverList tables169 level calibration94 telescopes,typesof 34 leveling the tripod85 TheSky light pollution14, 104 observationlog 16 - animation 128 local siderealtime 11 observation programs118 - configuration 122 longitude,accuracy foralignment observation technique 15 - description 121 85 open clusters27 -eclipsefinder 130 longitude,enteringon hand control -findingobjects 127 77 -installation122 PC control -labels 127 - ASCOM drivers 189 - moon phasecalendar130 magnification32 - cables required187 - object filters125 magnitude12 - commonproblems190 - objectinformation127 magnitude,surfacebrightness13 - description 185 - printing 130 maintenance215 -fieldpower 187 - setting dateand time 122 Maks SeeM aksutov-C assegrain - softwarecompatiblewith - sky documents129 telescopes NexStar277 - solar systemview 130 Maksutov-Cassegraintelescopes38 - suitablecomputersand - Virtual Sky 123 manual handcontrol 171 palmtops186 - zooming in and out 125 Mars 22,110 - USBto serialadapter186 time zone setting 75,96 mechanicaladjustments PEC Seeperiodicerrorcorrection trackingdrift 246 - NexStar 60/80/114223 periodicerrorcorrection98 transparencySeeseeingconditions -NexStar4227 piggyback camera mounts 169, transporting SCT scopes 241 - NexStar 5/5i/8/8i 220 197 tripodmodifications 145 - NexStar 8/11 GPS219 planetariumsoftware 106 tripod, feetfallout 251 Mercury 21,110 planetarynebulae28 tripod,mountingNexStar8/11 GPS Messier catalogIII Pluto 24,III 251 meteors andmeteorites25 power related problems240 tripods 141 Moon 17, 109 power sources149 motorcontrolboardreplacement 253 Uranus 24, III motorcontrolversions64 Ray's Bracket234 user defined objects,hand control motorvibration, NexStar 8/11GPS red lightIS feature96 253 refractors34 mounting rails 168 right ascension II RS-232mode 95 Venus 21,110 run away slews 254 version, hand control andmotor nebulae28 control102 Neptune 24, III video cameras195,205 Newtonian reflectors 35 satellites 25 NexStar 60 48 Saturn 24,III NexStar 80 50 Schmidt -Cassegrain telescopes 36 wedges 149