Event Horizon Event Horizon Archives 18 April Meeting Roundup by Mike Spicer (Continued from Front Page)

Volume 15, Issue 5 John Gauvreau on Things We Never Think May 2008 About Photo and Story by Mike Spicer

There were very few From The Editor’s Desk seats empty for the Hamil- ton Amateur Astronomers' Every year in the spring we celebrate April meeting at the Spec- Astronomy Day as an opportunity to tator Auditorium Friday do outreach to the community. All we evening, 11 April 2008. need do is look around the club and see all of Fifty members and almost the grey hairs to realize that we need to do a a dozen guests were in better job of getting young people interested in attendance for our line-up astronomy. Photographs of HAA meetings of excellent speakers! from many years ago show a lot of young people. How do we get them interested in our Club Observing Director hobby? One thing is certain, if we don’t get Prof. Greg Emery gave a new people interested, there are going to be a very detailed run-down of lot of telescopes sitting idle when we are all the Sky for April to aug- too old to lift them anymore.

(Continued on page 2) Tim Philp, Editor

Inside this issue: NOTICE Chair Report 3 Astronomy Day at Bayfront Park Image Stacking 4-5 in Hamiltion. Saturday May 10th Taking Care of Your Telescopes 7-8 @ 20:00 hrs. The Sky this Month 9—11 WEATHER AND CLOUDS PER- Knowns and Unknowns 13 MITTING! 4-D Ionosphere 16-17 Check the web site for directions.

Event Horizon Event Horizon Archives 18 April Meeting Roundup By Mike Spicer (Continued from Front Page)

ment his very informative arti- tions, pick up free magazines our 15th anniversary dinner cle in last month's newsletter, and copies of our club news- venue this fall. the Event Horizon. letter Event Horizon (thanks, Tim and Don), buy member- John Gauvreau was the ships or check out the new Glenn Muller announced an night's main speaker, enter- HAA caps and jackets (more HAA "road trip" to the Cherry taining the whole group until on that from Jim at May’s Springs Star Party in Pennsyl- 10 pm with his enthusiastic meeting). vania at the end of May, giv- presentation on ten astro- ing some impressive "dark sky nomical items we seldom site" information. Mike Jeffer- After the break, Jacob drew think about, from Greek geo- son presented on recent ob- the door prize winners and metric calculation of the dis- servations of our LOFAR radio Gail Muller and Gary Kre- tance of the Sun, to the mini- telescope and answered venky were presented with mal separation of neighbour some interesting questions, their Sky & Telescope Aurora galaxies. thanks guys. posters. Our 50/50 draw net- ted $43 for a grateful visitor - After the meeting, about two Dave ("and a membership is Members and guests used the dozen members retired to Kel- only $25"). Club members break to drink coffee (thanks, sey's on Main Street for din- voted overwhelmingly for a Jim), eat Timbits (thanks, ner, discussion and to wish Ed buffet-style for about $25 at Steve), watch AV presenta- a happy birthday.

Treasurer’s Report— By Don Pullen

(Unaudited) Cash opening Balance (1 Apr 2008) $ 3,026.26

Expenses $ 88.23 Revenue $ 160.00 Closing Balance (30 Apr 2008) $ 3098.03 Notes: Major expenses included: Newsletter printing (Apr) ($70.63), Speaker’s Meal (Feb $17.60). Major revenue sources included: Memberships ($55.00), 50/50 Draw (Apr $42.00), Donation ($43.00), Messier Marathon ($20.00).

Page 2 Event Horizon From the Chair by Mike Spicer

May brings warmer weather, boosting sions and Steve Germann volun- 8. Council heard that this year's Hamilton Amateur Astronomer observ- teered to drum up publicity for: May BASEF judges, Don and Jim, had ing and public demonstration efforts. 24th at Murray Street Park in so much fun that they volunteered Posting of observing reports on the Grimsby from 8-11 pm; July 12th to serve next year; Jim presented HAA blog is up and the number of peo- from 8-11 pm at a Burlington loca- the Winger Prize, an autographed ple attending our sessions is increas- tion Steve Germann will select; copy of "Nightwatch" and a ing, too. Why wait for July to start ob- August 12th from 8 pm at Binbrook cheque for $50 to Stephen Hogg, serving? Conservation Area for Perseid me- our 2008 science fair winner; teors; September 6th from 7 pm at Spring has some clear skies of won- the Brantford Tourism Centre, Tim 9. Chairman Mike advised that the derful transparency... use them be- Philp to book the site. No public May meeting will feature a do- cause the heat of summer can bring observing in July (too bright). An nated telescope as the door prize. smoggy evenings and night skies grey HAA excursion to Onondaga Farm Glenn Muller will talk in May on with light pollution. Observatory was suggested; Tim "Forces of Nature" and Mike Philp is meeting with the Program Spicer has "the Sky this Month"; Speaking of transparency, I have al- Director and will report at next the June meeting will bring Eric ways felt that members of the club Council meeting; Don Pullen is Briggs and a talk on "Telescope should know what their Council is do- checking into the Saltfleet High Secrets" by Ray Khan from To- ing. Members are of course welcome School Observatory. Members ronto; to attend Council meetings but most voted overwhelmingly at the April cannot attend for one reason or an- meeting to hold our Club's 15th 10. Tim Philp advised that a winner other. Would it be helpful if there was anniversary dinner at the Mandarin has been chosen for the 2007 an article about Council's activities, or a similar buffet-style restaurant. Telescope Contest, more informa- available in the Event Horizon or on Council appointed Don Pullen and tion to follow, leaving the way the web site? The official Minutes John Gauvreau to look for a open for Don to approach local can't be published until approved at the speaker for the dinner. papers concerning the HAA 2008 subsequent Council meeting and that Telescope Contest (the Chairman means a month's delay or more. But 4. Treasurer Don Pullen delivered a has donated telescopes for this an unofficial report on Council meet- detailed report on our healthy finan- cause); ings might keep everyone better in- cial situation which I suggested formed as to what is being decided, should be published in the Event 11. All members of Council have re- and who on Council is doing what. Horizon as a mid-term report card; ceived the HAA brochure in print- able format and Don has begun So here is what I recall of our last 5. Secretary Darrell Maude, busy re- updating the information; Mike Council meeting: cording the Minutes, advised there Spicer has donated 500 sheets of had been no club correspondence thick paper and Council budgeted Council met at Jim Wamsley's in Dun- received in the past month save for $25 to Steve Germann to print das on 16 April starting at 7:30 pm. new membership applications; Jim 500 copies of the brochure for use There were 12 items on the agenda: had mailed out Event Horizons to 6 at public events; non-computerized members; 1. Council decided that Astronomy 12. Council voted to raise the Event Day Saturday May 10th will fea- 6. Membership Director Jim Wamsley Horizon budget by $75 to in- ture a public viewing night from 8 reported 2 new memberships in the crease newsletter copies from 50 to 11 pm in the parking lot of the previous month, plus the winner of to 70 in each of May and June, Bayfront Park, as the Discovery the April 50/50 draw generously plus to make 50 copies of a sum- Centre grounds are no longer had returned his winnings and mer issue. Steve Germann is look- available without paying a fee. Council decided to give him a ing into lower pricing to copy the membership once we have his Event Horizon on 11 x 17" paper. 2. Tim Philp reported that the "Movie membership info; Jim demon- about HAA" he undertook to make strated the proposed HAA jackets Hamilton Amateur Astronomers is not will not be ready for Astronomy and baseball caps; Council voted a club of armchair observers. It's ac- Day but he will bring a rough draft to order 25 caps for sale at the May tive observers attending our meetings of it to view at our next Council meeting @ $15 each. in great numbers. My thanks to those meeting, May 14th. members who volunteer to help plan, 7. The bylaw review committee hopes organize and carry out its many won- 3. Council set the dates and times for to meet in the next month; derful activities. summertime public observing ses-

Volume 15, Issue 5 Page 3 Image Stacking One of the Keys to Success in Digital Astrophotography By Kerry-Ann Lecky Hepburn

When I first started to take pictures ground with some colour noticeable I could have more control in preserv- of deep sky targets with my digital in the galaxy. It is usually just after ing the dynamic range of the galaxy's SLR and telescope I was thrilled to this point, when you decide to bright cores and outer faint bands. just see a hint of the object on the brighten it up with processing, and back of the camera LCD. There this is where you begin to realize Figure 3 is a final stack of 38 frames were often times when I would think the problem with noise. with even further processing to bring the image looked great and that all it needed was just a little tweaking to be ready to show. Much to my sur- prise, once it was loaded and enlarged on the computer screen it was rather disap- Figure 1 pointing. When I tried to process it, there was not Figure 2 is an example of M51 after out detail and colour.. much detail nor colour and it was basic processing with a various As you can see the filled with lots of noise. number of Number of Stacked Amount of Noise Com- more images that are stacked 3 Images pared to the original After showing my results to veter- minute ex- stacked the more you ans in astrophotography, they posures at can increase the sig- would often tell me that I needed to ISO800. The 4 1/2 nal to noise ratio. take more frames and stack them basic proc- This will allow you to together. It took me a long time to essing or stretch and process really understand the benefits. I stretching is 9 1/3 the target to bring out started by stacking 2 or 3 frames of needed just even fainter details. the target, then months later aimed to bring it up The relationship for for 10 to 15 and now 30 or more. to a reason- 16 1/4 reducing noise boils It's hard to really understand the able bright- down to the inverse square law. impact of stacking until you actually ness and 25 1/5 test it out and see it for yourself. contrast so that you can For example, Figure 1 is a 3 minute see the gal- 100 1/10 Free and simple to exposure of M51 at ISO800 straight axy and its out of the camera with no adjust- use software like details. In 'Deep Sky ments other than converting to jpeg. these examples I stretched with the Stacker' (DSS) makes this process It looks dim but has a smooth back- curves tool instead of levels so that

Page 4 Event Horizon Image Stacking One of the Keys to Success in Digital Astrophotography By Kerry-Ann Lecky Hepburn

Figure 2

very doable and should be included as part of your basic pre- processing routine. With DSS, all you have to do is load your image frames (called 'lights'), check off the appropriate settings and away it goes. After the stacking is complete, save it as a 16-bit tif file and then open it up in a program for image processing. Of course for even more benefits from these kinds of programs, you should also stack your images with several dark frames to smooth out the background noise and get rid of those pesky dead pixels. Plus, take a series of flat frames to reduce the appearance of dust motes/dirt on your camera sensor and eliminate vignetting from your lens or telescope. As always don't forget to switch your camera into RAW mode before you shoot.

Stacking is a very easy process and the benefits can be seen above. Your final image will look cleaner and is much easier to process for colour and fine detail. So next time you are out taking astro-photos, snap as many frames as possible and start Figure 3 stacking!

Page 5 Newsletter Title Get Ready to (Star)Party! By Steve Germann

Mark your calendar as this year gathering place for amateur as- area. The disadvantage of this promises to be the most active tronomers, with particular hon- park is that we had to set up and one yet for summer star parties our given to those who built their tear down each day. That's not and HAA involvement. own telescopes. It's held at a problem with the other parks In Late may, there's the Cherry Breezy Hill in Springfield, Ver- on the list. Springs Star Party, in northern mont on a moonless weekend Pennsylvania, to take place at in July or August. This year it is Skies were very dark, although the darkest sky site in temperate from July 31 to August 3. Cost is clouds also made an appear- eastern North America. There, about $50. ance later in the nights. This when a cloud wafts by at night, year the moonless weekend is it's black. The next weekend, there's Star- proceeding up to the Labour fest, near Mount Forest, Ontario. Day Weekend, which means we About 10 members of our club It's got daily events August 7-10, need to plan early to get space will be heading out on Wednes- and HAA is always well repre- in whichever park is chosen, al- day or Thursday, and will set up sented. though the best nights will be a small piece of HAA territory on Advance arrivals as early as weekdays before that. the otherwise open field, which Tuesday evening can be re- accomodates up to 500 as- warded with dark skies. Cost Anytime from August 26 to La- tronomers, and also features a estimate is about $100. bour day will be dark. For those Saturday evening public viewing who may not want 3 camping event. Electronic registration is In September, the traditional trips in the month of August, still open until May 10, so you season-ending camp-out at an there's the possibility of an event have to act quickly if you are Ontario park, will finish the from September 25-28 instead. still on the fence. Just $37. camping for the season. Last Cost estimate is about $80 for year's event was at Silent Lake the reservations. It's a team effort this year, with Provincial Park, which has very various people taking on differ- dark skies, if not a 360 degree All together, the GWS might fun- ent tasks related to food and view of the horizon. Last year at nel the light from 15 dark sky shelter, and it should be a great Silent Lake, we had 3 good nights. It's practically gleaming star party. nights of observing, using the with anticipation. day-use parking lot as our setup In early July, there's a chance for a camping trip NYAA organized by the HAA. We will set up in a provincial park either on Manitoulin, Tober- mory, or near Huntsville, for 4 days of darks skies, and magnifi- cent views of the summer milky way.

At the end of July, Stellafane is the

Page 6 Newsletter Title Taking Care of Your Telescope Equipment by Ray Khan

In the course of doing tele- So, Here are a few tips on tak- diagonal. Also cover the scope repairs and mainte- ing care of your Telescope and front of your instrument. nance we do see a lot of in- other Optical Equipment: Most telescopes today stances where some preven- come with some sort of dust tative measures might have 1. Store your equipment in a cover for the Front Objec- saved a trip to the shop. dry area. Try to avoid any tive. For Dobsonians and musty or damp areas as it is Newtonians, you may be Over the years, we have seen possible for fungus to dam- able to find some Inexpen- some interesting things: A age your optics over a pe- sive plastic covers in the Hornet's nest in the base of a riod of time. plumbing section (used to customers Schmidt- Cover your equipment with cap the ends of pipes). Cassegrain telescope drive a breathable cloth material base. Grasshoppers crawling if possible, or at the very 3. Store your eyepieces and inside a SCT corrector plate least a tarp, or even gar- accessories in Cases. leaving a "wonderful" resi- bage bag is better than Avoid putting them in coat due. Dog and Cat hair inside nothing. pockets, as they will often a Dobsonian telescope. Cob- pick up small pieces of lint, webs in telescope tubes 2. Keep dust out of your op- which are difficult to re- (complete with dead spider!). tical system: Put a plastic plug in any focuser, or Star Continued on page 8

Volume 15, Issue 5 Page 7 Taking Care of Your Telescope Equipment Continued by Ray Khan

move. That extra Jovian sat- pieces and other telescope Do not leave in your car ellite you see, may be as accessories. as changes in tempera- such. The other benefit is ture can do damage to the that when you are finished 5. Carry a product called a cement in the objectives observing, you know every- "Lenspen", available at over time. If you want to thing is accounted for and Telescope and Photo keep a pair for handy use, where it should be. stores, which allows you to better to buy an inexpen- remove fingerprints from sive "back up" pair. Also: 4. Before storing your equip- Eyepieces and Maksutov The knocking around in a ment after use: Ensure that and Schmidt Cassegrain car trunk can affect the all surfaces are dry. corrector plates. If finger- collimation (causing a If necessary, let the equip- prints are left on for a period double image) of your op- ment air dry completely, be- of time, they will etch into tics. fore storing it away. Just use the Coatings. (Great way of a dry soft cloth on the tube identifying a telescope if it is So, protect your optical in- (but be careful not touch the stolen, but not much else!). vestments and they will re- Optics as tempting as it may ward you with years of ob- be) same goes for your eye- 6. Binoculars: Do store them serving pleasure! in the case they came in.

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Page 8 Event Horizon The Sky this Month—by Greg Emory

The Messier List, in current times, consists of 110 items. There are roughly 40 of these visi- ble on the centerfold this month. The chart is for May 15 at 10:00 pm (Local Time). Once again we can see a wide variety of objects this month. Setting in the west we have Gemini. Mars has traveled eastward over the last month or so. The red planet is still located in the Western skies. It is now in the constellation Cancer, a few degrees away from M44, the Beehive or Praesepe, which is a stunning open cluster located in the heart of the crab. Saturn remains anchored in the forequarters of Leo. A short distance from Regulus (α- Leonis) it is quite easy to find, it is the eastern partner of the bright pair of “stars” more or less straight overhead. Time for viewing Saturn is running out, by mid July, Saturn will be setting with the Sun. As we loose Saturn, we gain Jupiter. Set in Sagittarius, Jupiter will be a presence in the Summer Milky Way. The 4four larger moons of Jupiter are easily seen with binoculars. Their relative positions change noticeably during long observing sessions. Sagittarius rises in the east just before 1:00 am in early May. The planet should be in good viewing position by 3:00 am. The late night will reward all planet observers. A relatively close grouping (OK 100 degrees may not be close) of planets extends across the sky from Jupiter to Venus, which is with 10 degrees of the Sun in Early May. In the constellations Capricornus the planet Neptune is hiding, whereas Uranus can be found in Aquarius. Venus is in Pisces with the rising Sun. The centerfold of this months EH shows Coma Berenices directly overhead. The constellation appears more impressive in the centerfold than in the sky. Under typical skies in the suburban environment, the three brightest stars be hard to see. From a dark site, the three stars mark the location of scores of galaxies and other faint, fuzzy stuff. Although technically the bulk of galaxies beneath Coma Berenices are actually in Leo or Virgo, they are just as easily found coming down from Coma Berenices. Moving eastward from Coma we find M3, a bright globular cluster. The cluster M3 is nice, but I always seem marginally unim- pressed. Perhaps it is because I know what is coming, or I am being too picky. The cluster is a nice one to look at and well worth the time or effort. Some other globular clusters are coming up as well. The clusters M5, in Serpens, and M12 and M14 in Ophiucus are readily seen in small scopes. A very nice globular is found in the constellation Hercules. Between his arm and shoulder is M92. This cluster is bright and resolvable. I have repeatedly in the past spoken or written about M13. Forget about M13, look at M92. Regardless of which globular you are viewing take a few minutes to allow your brain to process what you are seeing. Globulars are classified by brightness, how tightly the stars are grouped together and how many of the stars are resolvable as individual stars. Some globulars are faint cotton balls with few if any stars resolvable. Others are bright objects which can be resolved to the innermost regions in moderate to large scopes. Take your time when viewing them, you may be surprised at what you can see.

Page 9 Event Horizon The Sky T his Month Through the Looking Glass—by Greg Emory

The early spring offers no better cles wrapping around the body. based on your last name. time to talk about galaxies. Galax- The Spiral classification is denoted ies in general are one of four by an S. The number after the S If the story and classification issues classes of a group of objects As- will refer to how tightly the arms are ended there, then this article would tronomers call Deep Sky Objects wrapped around the central core. be 250 words or so shorter. All gal- (DSO). Deep sky objects refer to The S0 galaxies will have tightly axies move through space. As they things which are beyond our solar wound arms, where as an S3 has are moving they also rotate about system. The four members of the much looser winding. some axis. For an elliptical or len- group are galaxies, globular clus- ticular galaxy, this really doesn’t ters, open clusters and nebulae. The barred spiral galaxies (SB) are matter to us, a tennis ball or an egg very similar to spiral galaxies ex- look pretty much the same regard- When we view any object in astron- cept that the central core (or body less of which way you look at it. omy we are in essence, looking of the octopus) is distorted and is Spiral and Barred Spiral Galaxies back in time. Stepping out- don’t have this symmetry. side and allowing the warm Looking down onto the face of Spring sunlight to fall upon a clock we see the hands your face is an act of experi- moving in one direction. If we encing history. The warmth could view the clock from un- of the sunlight left the Sun derneath the hands would ap- roughly seven minutes be- pear to move in the opposite fore, while you were still in- direction. This same phe- side looking for your sweater! nomenon is at play when we This may not seem historical view the spiral classes. When to you, however consider this: viewing galaxies we can see when we see the Sombrero them from the top (North Pole Galaxy (M104 in Virgo), the or 0 Degrees presentation) or light packets (photons) that from the bottom (South Pole are striking our retinas to pro- or 180 Degrees presentation). duce the image left the galaxy 50 Million years ago. We see The final complication or con- the image of the galaxy as it sideration when looking at the was 50 Million years ago, we spiral galaxies has to also do are seeing the past. It is pos- with the angle of presentation. sible to look upon a galaxy A spiral galaxy is typically and see that galaxy as it was shaped like two dinner plates when Dinosaurs roamed the placed on top of one another earth. in opposite directions. Place a dinner plate on the table in the Galaxies come in five main normal manner. Place a sec- types or classes. These clas- not round. The core tends to be ond plate, upside down, on top sifications are elliptical; lenticular; more oblong or cylindrical with the of the first. This is what a spiral spiral; barred spiral and irregular. arms emanating from the ends of galaxy typically looks like in three Elliptical galaxies are given the the distorted core. Again the nu- dimensions. From above or below class letter E followed by a number. merical designation after the SB the plates look round, this is view- An E0 is essentially a round galaxy. indicates the way the arms are ing from the North or South poles. As the number in the designation wrapped around the core. The plates look much different if increases in value, so does the el- you lower your eye to the level of liptical nature of the galaxy. The If any galaxy doesn’t fit the above the table top, however. The edge galaxy will have a definite oval classifications, you have one of two on view changes the circular profile shape. options. The first is it can be classi- of the galaxies or dinner plates to a fied as irregular (Irr). The other op- cylindrical or almost linear profile. A lenticular galaxy is basically a tion, if you happen to be a profes- These views are referred to as 90 round ball. A spiral type galaxy sional Astronomer, is to create a degrees presentation or 270 de- looks like an octopus with the tenta- new classification type, usually grees presentation.

Page 12 Event Horizon Knowns and Unknowns by Steve Germann

There are known unknowns, and un- The problem of a secondary mirror ence in diameter of the support pillar known unknowns.... dewing up was completely unantici- for the mirror and the oval hole in the To me, the clouds at night were in the pated by me, but fortunately not by PC board of the dew guard. There former category. I never knew in ad- the Kendrick Astro Instruments com- was no time to send it back and wait vance which night would be clear, but I pany. for a redesign. had a pretty good idea how long it They designed a clever gadget which Luckily, I have a machinist friend, and would last if it happened to be clear, attaches to the back of the secondary a soldering iron. After a few judicious thanks to excellent short term weather mirror and applies just enough heat to markings with a black marker, and prediction technology. keep it a few degrees above ambient some assistance from him, (who to However, once I had the scope setup temperature. my horror, just picked up a hand file and the sky was clear, I thought it This results in almost no air currents, instead of firing up some fancy electric would be clear sailing. since several small heaters are in cutter), the board was appropriately Little did I know about the latter cate- direct contact with the back of the shrunk, and the oval hole enlarged. A gory. few soldered patch wires later and I remember the first time I took the the thing was as functional as on the GWS to Binbrook. All the MAK's were day I bought it, but it also fit the dewing over, but the GWS, with its GWS. noble white shroud, stood firm and There's a little temperature sensor was only taken down when it's owner for detecting the air temperature, and considered the prospect of being there's a little red LED which lights locked in the park overnight. when there's heat being applied. (I must remember to buy a combina- To test it, I just touch the tempera- tion lock). Well, that lasted a good ture sensor for a moment, and the week or two. light comes on reassuring me that The mighty dew-proof GWS served the battery is still good and that the me well after 4 AM on the first clear temperatures are right. night of Starfest 2007. As long as temperatures are falling, However, the GWS has a 3.5 inch the DG-35 has an easy time. It's secondary mirror too, and I was dis- when the temperature is rising that mayed to see it fog up that night at mirror. And since the temperature things can get difficult for it. Starfest. gradient is so small, there's no distor- Fortunately, a 9v Ni-MH battery has a The shroud and built in fan protected tion of the mirror either. pretty hefty current available. the primary mirror pretty well; I never Another plus is that the DG-3 runs on Increasing the wattage would require suspected the secondary, facing into any voltage from 5V up to about 24V, increasing the applied voltage (or the scope, could dew over. and that includes the 7.2V that comes making circuit modifications). Score one for the unknown unknowns... from a Ni-MH '9V' battery. It runs all If the light comes on and stays on for which then moved over into the first night off a tiny 9v battery, which until more than a few minutes, it's time to category. recently, I have hidden just behind the reach for a hair dryer and give the I set about attempting to make sure the secondary mirror, out of the light path. mirrors a boost of heat. secondary never dewed up again. I have 5 such batteries A dew shield is a common require- One of the advantages of attending a (rechargeable), at the ready for my ment for a SCT or MAK scope, but in star party such as Starfest is the great camping trips. Recharge time is about the case of a Newtonian, something supply of people who have done recent 14 hours, but not having to run wires often overlooked. If your secondary shopping for astronomy equipment, to the secondary is a plus. has never dewed up yet, it's even and are able to share their experi- The next big trip of 2007 was planned more useful to get a dew guard, be- ences. for early September, to Silent Lake cause dew, once dried, helps any dust An additional plus is that people tend to Provincial Park, and there promised to on the mirror stick and not be easily visit others with the same kind of be more complete-night dark skies to blown away. scopes, and the scopes are there for all catch, so there was no time to lose. Rearranging a store-bought circuit is to see, from a hundred yards away It turned out that still more unknown not for the faint of heart. At the time (especially the GWS, which was set up unknowns came into play; the GWS the LB-16 was a new scope model. on the hill). secondary mirror is arranged on its I think by now Kendrick will know I had the pleasure to consult with sev- support in such a way that the DG-3 which of their devices will fit your eral large Dob owners who were able did not fit cleanly, and was not only scope, and you won't have to encoun- to give me advice about accessories for blocking the light path, but was also ter any of the now-known unknowns the (at the time, less than one month impossible to secure in place against that I came across. old) GWS. the secondary mirror, due to the differ-

Page 13 Event Horizon A Thank You Note By Stephen Hogg

Page 14 Event Horizon Newly Refurbished Planetarium Opening!

Toronto, May 1, 2008~–~Marc Garneau, Canada’s first astronaut in space, unveiled today the newly refurbished CA Planetarium at the Ontario Science Centre. Toronto’s only public planetarium now has state-of-the art multimedia technology thanks in part to a five-year contribution from enterprise software company CA Canada.

The new CA Planetarium has a cutting-edge combination of projector technologies, state-of-the-art 3D digital software and imagery based on real-time data that will allow audiences to feel as though they are flying through the universe. The planetarium show provides visitors of all ages with a spectacular view of thousands of objects in space, such as stars and galaxies beyond the Milky Way.

“We are grateful for CA Canada’s generous donation to help re-open Toronto’s only public planetarium,” said Lesley Lewis, CEO, Ontario Science Centre. “Prior to this restoration, our planetarium relied on aged technology that presented constrained views of space. Now, we can offer Canadians an impressive view of our solar system and inspire visitors to see, understand and think about the world in a new way.”

National survey: hands-on experiences prompt student interest in science and technology

A survey conducted for CA Canada by The Strategic Counsel released today indicates that nine in 10 Canadian university students say that trips to science centres and museums increased their interest in science and technology.

At a time when many Canadian educators are concerned about students' declining interest in science and technology, the survey reveals that students' interest in these subjects increases with hands-on, interactive experiences.

Among the findings:

• 94 per cent of those surveyed said that trips to science centres and museums increase their interest in science and technology.

• 90 per cent said high school math, science and technology should include more hands-on learning.

More than half (53 per cent) of students who are not studying science or technology said they would be more likely to pursue university studies in these fields if they had been able to do better in math, science or technology in high school.

The survey of 482 Canadian university students also revealed that the top three reasons for not pursuing science or technology as a career choice in post-secondary education are that these fields of study are seen as "too complex," "too boring" and provide "uninteresting" work.

“Students are clearly saying that high school science and technology classes should have more hands-on learning to increase their interest in these subjects, making it more important than ever to bring children on school visits to science centres, planetariums and museums so they can see the excitement of science and technology in action,” said Garneau. “The CA Planetarium will allow kids to learn about astronomy and space in a practical, fun and engaging way and help foster interest in learning more about science and technology at a young age.”

The refurbishment of the Ontario Science Centre’s Planetarium was supported through CA’s Together Community Grants, a program that supports organizations that focus on promoting education and technology.

“Over the past three decades, CA has supported many organizations that focus on education and technology, and has helped these organizations promote learning and make science interesting,” said Jimmy Fulton, vice-president and country manager for CA Canada. “Our commitment will allow the Ontario Science Centre to continue to pursue its goal of making science accessible and engaging to visitors of all ages, and increase the likelihood that young Canadians will choose a career in science and technology.”

The CA Planetarium is part of the Ontario Science Centre’s newly renovated Space Hall. Regular daily shows will be available to the public beginning at the end of May.

Page 15 Event Horizon 4-D Ionosphere by Dr. Tony Phillips

NASA-funded researchers re- nals off of the ionosphere—or work," says Guhathakurta, LWS leased to the general public a communicate not at all when a program scientist. Space Environ- new "4D" live model of Earth's solar flare blasts the ionosphere ment Technologies, Inc. of Califor- ionosphere. Without leaving with X-rays and triggers a radio nia received the LWS grant and home, anyone can fly through blackout. The ionosphere also they partnered with Space Environ- the layer of ionized gas that en- has a big impact on GPS recep- ment Corp. of Utah and the US Air circles Earth at the edge of tion. Before a GPS satellite sig- Force to develop the 4D iono- space itself. All that's required is nal reaches the ground, it must sphere. a connection to the Internet. first pass through ionospheric "The best way to appreciate the 4D gases that bend, reflect and at- "This is an exciting develop- ionosphere is to try it," says W. tenuate radio waves. Solar and ment," says solar physicist Lika Kent Tobiska, president of Space Guhathakurta of NASA head- geomagnetic storms that unset- Environment Technologies and quarters in Washington, DC. tle the ionosphere can cause chief scientist of its Space Weather "The ionosphere is important to GPS position errors as large as Division. He offers these instruc- pilots, ham radio operators, 100 meters. Imagine a pilot fly- tions: earth scientists and even sol- ing on instruments descending "One, download and install Google diers. Using this new 4D tool, toward a landing strip only to Earth." they can monitor and study the discover it is a football field to ionosphere as if they're actually the right. "Two, visit our web site and click on inside it." the link 'Total Electron Content.'" The ionosphere is, in a sense, "Understanding the ionosphere our planet's final frontier. It is is clearly important. That's why Wait for the file to load and presto— the last wisp of Earth's atmos- NASA's Living with a Star you're flying through the iono- phere that astronauts leave be- (LWS) program funded this sphere: screenshot. hind when they enter space. The realm of the ionosphere stretches from 50 to 500 miles above Earth's surface where the atmosphere thins to near-vacuum and exposes itself to the fury of the sun. So- lar ultraviolet radiation breaks apart molecules and atoms creating a globe-straddling haze of electrons and ions. Ham radio operators know the ionosphere well. They can communicate over the horizon by bouncing their sig-

Page 16 Event Horizon 4-D Ionosphere (Continued) by Dr. Tony Phillips

"Colors represent electron con- tic. "A growing number of com- cause a flight to be delayed or tent," Tobiska explains. "Bright mercial business flights are cross- diverted. red is high density; that's where ing the Arctic Circle," he says. "It's the shortest distance between, The proper name of the system is radio communications are re- say, Chicago and Beijing and CAPS, short for Communication stricted to few or no frequencies. many other major cities." Alert and Prediction System. Blue denotes low density; no Earth-orbiting satellites feed the problem there." The ionosphere is particularly im- system up-to-the-minute informa- portant to these lucrative flights. tion on solar activity; the meas- Using the intuitive Google Earth While they are over the Arctic, urements are then converted to interface, users can fly above, planes lose contact with most electron densities by physics- around and through these regions geosynchronous satellites and based computer codes. It is im- getting a true 3D view of the must rely on "old-fashioned" radio portant to note, says Tobiska, that CAPS reveals the ionosphere not situation. Make that 4D. "The communications—a link that fourth dimension is time. This is a only as it is now, but also as it is could be severed during a radio going to be the near future. real-time system updated every blackout. Using the 4D model, a "Forecasting is a key aspect of 10 minutes," he says. flight controller could examine the CAPS available to our customers ionosphere from the flyer's point from, e.g., the Dept. of Defense The 4D model can be fun and and the airline industry." even a little addictive, warns To- of view and use that information biska, who likes to use it to pilot to anticipate problems that could an imaginary plane over the Arc-

Page 17 Event Horizon The Event Horizon Archives—Fun in the Sun By Grant Dixon—February 1995

When you are asked "told" to to successfully explain this phe- ceased. When Furness returned to write an article, you panic, you nomenon! observe the sun the next day there have a fuzzy brain moment and were no spots. While the solar sur- think, What to write?. face is very active, I am curious as to why this is Well, I sit here with a the only observance of blank piece of paper such a rapid change of and think what I should sunspot activity. write about. Should it be deep and erudite, or Fly Me Swiss Air light and whimsical; On January 22, 1959 should it be learned or Yngve Ohman, while ob- superficial? serving the sun at the As I type I realize eve- Stockholm Observatory, ryone loves the trivial, noticed a black object so why not something cross the sun. It created a about the sun? I have light surge that lasted two selected three short stories about seconds and extended two minutes Rapid Surface Change observing the sun: two anoma- of arc on either side of the sun. A lies and one just a curiosity. On January 22, 1900 at 3:00 p.m., month later a colleague of Dr. Oh- Caroline E. Furness was using the man made a similar observation. 17th Century Solar Rotation observatory at Vassar College to This caused a great degree of puz- For almost a century the sun observe the sun. She observed a zlement until someone thought that went into a period of very low sun devoid of spots for 15 min- maybe it was the crossing of sunspot activity now known as utes and then suddenly a spot ap- planes. The Swiss Air force was the Maunder Minimum (1645 peared. coaxed into supplying two jets to 1715). Just prior to this, there The sun was then projected onto a take part in an experiment. were two well documented ac- screen to make an image of 15 counts of sunspot activity. One The jets made two transits at a dis- inches in diameter. The spot was was between 1625 1626 and the tance of about 10 km and the re- now the size of a pinhead and other between 1642 1644. In sults were consistent with the ear- while she observed this one, an- both cases, astronomers were lier observations; therefore, the other and then another appeared, able to ascertain the rotation of hypothesis was proven to be cor- and finally a fourth appeared. the sun. rect. Within 10 minutes all had faded The surprising finding was that with the exception of the first one. To my knowledge this is the only just before the Maunder, the sun time fighter jets have been used in At that time the sun was getting rotation sped up by 3%. As far a scientific solar experiment. so low the observing session as I know no one has been able

Event Horizon Page 18 The Space Place—Stellar Compass for Space Explorers by Patrick L. Barry

In space, there's no up or down, The compass uses these signals— money. "If you're paying a million north or south, east or west. So how along with images of star positions dollars per kilogram to send your can robotic spacecraft know which taken by the camera—to measure ro- spacecraft to Mars, you care a lot way they're facing when they fire tation. about weight," Chmielewski says. their thrusters, or when they try to At less than 3 kilograms, ISC beam scientific data back to Earth? Because the Inertial Stellar Compass weighs about one-fifth as much as traditional Without the stellar com- familiar passes. It compass also uses points of about one- Earth's tenth as magnetic much poles, power, so a spacecraft spacecraft use stars would be and gyros to able to use know their smaller, orientation. lighter solar Thanks to a panels. recently completed Engineers test flight, at Draper future Laboratory, spacecraft the Cam- will be able Compass is built as two separate assemblies, the camera-gyro assembly and the data processor assembly, con- bridge, to do so nected by a wiring harness. The technology uses an active pixel sensor in a wide-field-of-view miniature star Massachu- using only camera and micro-electromechanical system (MEMS) gyros. Together, they provide extremely accurate infor- setts, com- an ultra-low pany that -power camera and three silicon (ISC) is based on this new, radically built the ISC, are already at work wafers as small as your pinky fin- different technology, NASA needed on a next-generation design that gernail. to flight-test it before using it in im- will improve the compass's accu- portant missions. That test flight racy ten-fold, Chmielewski says. So "The wafers are actually very tiny reached completion in December ISC and its successors could soon gyros," explains Artur 2007 after about a year in orbit aboard help costs—and spacecraft—stay Chmielewski, project manager at the Air Force's TacSat-2 satellite. on target. JPL for Space Technology 6 (ST6), a part of NASA's New Millennium "It just performed beautifully," Find out more about the ISC at Program. Chmielewski says. "The data checked nmp.nasa.gov/st6. Kids can do a out really well." The engineers had fun project and get an introduction Traditional gyros use spinning hoped that ISC would measure the to navigating by the stars at space- wheels to detect changes in pitch, spacecraft's rotation with an accuracy place.nasa.gov/en/kids/ yaw, and roll—the three axes of of 0.1 degrees. In the flight tests, ISC st6starfinder/st6starfinder.shtml. rotation. For ST6's Inertial Stellar surpassed this goal, measuring rota- Compass, the three gyros instead tion to within about 0.05 degrees. This article was provided by the consist of silicon wafers that resem- Jet Propulsion Laboratory, Cali- ble microchips. Rotating the wafers That success paves the way for using fornia Institute of Technology, distorts microscopic structures on ISC to reduce the cost of future sci- under a contract with the Na- the surfaces of these wafers in a ence missions. When launching tional Aeronautics and Space way that generates electric signals. probes into space, weight equals Administration.

Event Horizon Page 19 The Event Horizon is a publication of the Hamilton Amateur As- tronomers (HAA) The HAA is an amateur astronomy club, for people of all ages and experience levels, dedicated to the promotion and enjoyment of astronomy . The cost of the subscription is in- Hamilton Amateur Astronomers cluded in the $25 individual or $30 family membership fee for the year. Event Horizon is published a minimum of 10 times a year. PO Box 65578 Dundas, Ontario 2008 HAA Council L9H 6Y6 General Inquiries Chair Mike Spicer [email protected] Membership Secretary Darrell Maude [email protected] Meeting Inquiries Treasurer/Vice-Chair Don Pullen [email protected] Public Events [email protected] Membership Director Jim Wamsley Observing Inquiries [email protected] Observing Director Greg Emery Newsletter [email protected] Event Horizon Editor Tim Philp Webmaster Bob Christmas

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