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Beginning Astronomy?
AnalogBoy asks: "I figure, with the diverse backgrounds offered here on
Slashdot, at least 1(,000) of you would have an astronomy background, in
some way, shape, or form. I've always had a passing interest in all things
space, in particular, i've always been captivated by whats 'out there'. I was
wondering if any of youse guys had suggestions on books, programs
(Windows or Unix), and especially GOOD telescopes (Sub-$500-range).
I've looked through Google, etc -
but I want a community opinion! "
You could pick up a decent telescope, though I'd recommend a reflector with at least basic controls. Before it got stolen, I used a Celestron 3.5 inch reflector (The link is a shot of mine.). I paid about $500 AUS for it while on vacation in Adelaide. Nice and light, good solid wooden tripod, with good starter instructions. Definitely scout around for a local place to stargaze. Light pollution is a real pain in the ass.
- billn
I once had an astronomy background on my desktop. But I got bored and changed it.
Have you read my journal today?
Check out http://www.telescopes-earth.com , they have a fairly good selection of telescopes from
:)
cheap $100 models to several thousand dollar scopes with integrated GPS and Star Finder systems.
I personally have a Celestron C-102 (lists for just over $500 on their site) which isn't the greatest scope in the world but I find it more than adequate.
The site also sells accessories (additional lenses, filters, etc), which are useful for people like me who usually have a camera attached to their telescope
/~mikeg
While i love astronomy as an interest, ive always found telescopes to be somewhat usless in terms of finding out whats out there. I mean, dont get me wrong, its great fun to take a look at planets and such through them, but ive always found reading about it more interesting, since theres only so much i can find out by looking up myself.
All Troll + "offtopic" mods are meta moderated as "Unfair", because you abused the system.
Amateur astronomy is an excellent, and quite rewarding, hobby. I've been an amateur astronomer, albeit a serious one, for about 15 years or so. My recommendations for every new astronomer is the same:
Far too many new astronomers enter into the field by purchasing a poor department store telescope, or conversely, purchasing an expensive instrument far beyond their capabilities and interest. Taking the time to look at the sky with your naked eyes will serve you better if you become serious about astronomy, or if you decide it's just not for you. If you just have to purchase something, check out binocular astronomy. Orion has a wide range of good binoculars for astronomy. Binoculars have a wide, rich field of view, they're extremely portable, and they have uses OTHER than astronomy. The benefits are obvious:
Good binoculars for astronomy aren't big on power, so avoid getting a big 'X' rating. What you're looking for is aperture (remember, aperture is about light-collection capability; more aperture, brighter images) 10x30 is the smallest binocular you'll find that's useful for astronomy, but an 7x30 can also be fun. 10x50 (~US$200)is about the best all-around binocular for astronomy, but 10x70s (~$300) can be found for reasonable prices these days. Orion has several nice binoculars for good prices.
Buying a telescope is another animal. I strongly recommend learning as much as you can about telescopes before purchasing one (you might even decide to build your own). Check out a book called Star Ware for an excellent description of common astronomical instruments, including a full rundown on scopes. Additionally, I would recommend searching out your local astronomical club. Astronomy clubs are generally filled with interesting people with expensive scopes and lots of good advice. You'll learn more with a club than though any other venue, and you'll get a chance to peer through those sexy scopes your wallet burns to purchase...BEFORE you buy one and have to live with it.
If you actually purchase a scope, my own preferences lean toward the Dobsonian Newtonian. (A Newtonian reflector on a Dobson mount) These things are easy on the pocketbook, have enormous apertures, and really let the beginner learn the ropes of astronomy before becoming encumbered with the automatic push-a-button-see-a-star stuff that Meade wants to sell you. You'll find lots of good stuff at Orion in the range of $300 to $500 - their 6" Skyquest Dob is currently $349. Having owned the first version of this scope, the Deep Space Explorer, I recommend this scope wholeheartedly for a first scope. Buy this and spend the rest on eyepieces (a subject I shan't broach) for a really fun scope that will serve you for years. It's portable (sorta bulky, but portable), big, clean, and perfect to get your feet wet.
Feel free to contact me if you have questions. I have LOTS of opinions that I generally dole out for free. :) Have fun!
What'dya mean there's no BLINK tag!?
the field of view is broad enough that you can see the context of what you're looking at, to match with star charts. A good pair will set you back between $100-300. For best results, look for "long eye relief" and try to keep the ratio of the aperture to the power below 7 (e.g., 7x50 binocs have a ratio of 50/7, or just over 7). Binocs don't need to be polar-aligned, which is a pain in the a**, except on the new GPS-equipped scopes that are definitely too pricey for beginners. Also, check out Heavens-Above.
The best way of getting into astronomy is through your local club. There are several in the greater boston area so I imagine there must be a few where you are. Here is a link to one club listing
;-)).
:).
http://www.astromart.com/links.asp?c=1
Most clubs have observing places that you should visit on clear nights. Best way to make like-minded friends and get educated about equipment, etc (and to really find out if 'standing in one place in sub-freezing temperature for several hours in pitch dark' is your idea of fun
Once you get into it, you'll have more suggestions than you'll want and more equipment you'll want to purchase than your wallet can afford
PS: NH Astronomer Ed Ting has a great website reviewing telescopes http://www.scopereviews.com
Slashdot looks deep within my heart and assigns me a number based on the order in which I join
'nufff said!
if you need something to help identify just what the heck you're looking at....
Try xephem
It's a part of debian and (used to be) red hat I know.... it's helped me to figure out what a particular bright object is at times.
Blech. Signatures.
XEphem, is, hands down, the best astronomy program for any OS. You can get it at www.clearskyinstitute.org. The program itself is open source and includes a database of a few thousand stars plus the messier object. For a fair price, you can get three CDROMs that include binaries, an installation program, and a much-expanded database. XEphem is the best collection of astronomy resources I've ever seen for the PC, including everything you could possibly want to know about a given object. It also includes a driver for controlling LX-200 compatible telescopes. I use this program every night and intend to register it.
There was a previous "Ask Slashdot" question (December 2000) similar to this one that generated a lot of helpful comments. I realize the earlier question was aimed at what to do for a youngster, but many of the replies are equally useful for people of all ages interested in astronomy:
Getting Kids Started In Astonomy?
We bought my in-laws a 6" Dobsonian mounted Newtonian reflector and they've really enjoyed it. It is VERY easy to use and is powerful enough to be fun. Also, it didn't cost too much. It is easy to move around so they can take it out on a whim and it isn't so expensive that they are concerned about the grandkids destroying it.
Lasers Controlled Games!
You snuck this pathetic little comment in while I was typing a more complete one and made me look like a lamer.
Personally when I got into star gazing my grandfather gave me a book on grinding and building my own reflector telescope. So for the next few months I did, looking back now it wasn't the greatest telescope, but it meant a lot to me to be seeing Saturns Rings with something I built with my own hands.
It really isn't that diffucult to do, just takes time, and it is pretty cheap too, least compared to shelling out 500 bucks for a 3.5 inch reflector.
Here are some links for books and stuff:
http://www.willbell.com/tm/tm2.htm
http://www.hickorytech.net/~landsg/
Not to be insulting but you ought to think about taking and astronomy/cosmology class at a local school (Uni or community college) or maybe even a privately run planetarium. It might cost you a few bucks to take the class and buy course materials but you'll learn alot and by the end you'll have learned a bit. A good telescope is useless without having an idea of where to point it.
As for software and hardware The Sky for Windows and Mac is a good program which I've used before. You get the basic stuff like star positions and all that jazz but it also has a library of objects so you can look up useful data on different objects in the sky. It also has a night viewing mode where it reddens your monitor (for use on a laptop in the field) so you don't ruin your night vision. I can't really vouch for any other software because I've had The Sky on my powerbook for a while. There's a ton of open source astronomy software all over the place. The key to it all is knowing what sort of information you're seeing which goes back to taking an astronomy course somewhere. For hardware...that is a difficult suggestion. I'd say go for a good pair of binoculars at first with a nice size primary lens before you think about a telescope. Getting a telescope is a big investment for amateur astronomy and might leave you with an overwealming sense of "what the fuck do I do now".There's not a whole ton of stuff you're going to see with a telescope you can't see with a good pair of binoculars.
Another way to get aquainted with stuff is attend star parties. Check your local community college, university, or private planetarium for fliers advertising star parties or amateur astronomy groups. Alot of them will readily help you out getting into amateur astronomy. Once you're introduced to amateur astronomy and decide you like it get more expensive equipment, after you know what you're investing money in and have the ability to use it properly.
I'm a loner Dottie, a Rebel.
First, telescopes are all well and good, but your own eyes can show you the best of what the sky has to offer, (eclipses, meteor showers) and you need to know the night sky fairly well to know where to point a telescope.
A telescope will not show you stuff like the pictures you will see in magazines, that was a camera looking at the same thing for a long time, and then putting all those photons together in one image, something your eye can not do.
Which brings up another important point, in a telescope, magnification is not really improtant. If I get 100000X I get to look inside a crater on the moon, (and get crap resolution) or I can get a reasonable magnification and look at the entire moonscape (which I can say from experience is quite beutiful). What is important is collecting lots of light. More light means better resolution. that means you want a large aperture.
The other thing you need in a telescope is a mount, a stable one.
But in the end I have to agree with the the other long post here, you don't need a telescope to enjoy astronomy. The sights I remember most, are a lunar eclipse when I was about 10, a meteor shower while camping, The comets that past by about 4 years ago, and seeing saturns rings. Only one of those involved a telescope.
but if you really need a telescope, may I suggest Astroscan.
I hope these thoughts aren't too muddled.
I would have to reccomend to you as a starter, to forget about purchasing anything other than a few books and a star chart. Find a nice clear place (low light pollution, few trees, preferably a hill) and bring a very warm sleeping bag and wear lots of layers. Bring your star chart, a compass (to orient yourself) and a flashilight with a red lens (to prevent killing your night vision which can take a few minutes to reset). Armed with these items and circumstances, you can begin to learn the sky. Try to identify the various constellations. This may be tricky at first since making the leap from scale and position on a chart to in the sky can require some experience. This way you can learn to find stuff (like stars and planets) in the sky and just be amazed by the milky way itself. Laying down also prevents the dreaded "neck crick" and allows your vision to be filled mostly with sky.
Once you can find most of the positions of objects in the sky, you are ready to get a scope or binoculars and begin focusing in on particular phenomena and objects. You'll also find out if being in the cold and damp is something you can put up with. This is true especially because the skies are generally clearer in the winter months.
Done all that? Still interested? Well then, find your local astro club and join them because when you're not peering through the lens, it's nice to have someone to share your findings and "discoveries" with.
What scope to buy? Refer to the other replies here, there seem to be plenty of good recommendations. As far as star charts go, I personally prefer the rotating disc type that allows you to dial in the time of day and year to get a picture of what's currently in your sky.
Happy stargazing!
:::Horrendous Experiences Make Amusing Anecdotes:::
The first thing you should get hold of Xephem - a pretty good starmap/night sky program useful for locating things you want to observe. Once you have that, you should get some heavy duty image software, such as IRAF which I used extensively during my PhD. Take time to read the documentation available and absorb the methods used for analysing optical images - plenty of papers reveal in detail the methods used to identify objects and classify them according to morphology, colour profile or similar.
There are other sky plate analysis packages out there. Look for SExtractor (Source extractor) which some people prefer and which may make a better job of analysing nearby galaxies.
Also look out for tools in the links off a lot of these academic pages - there are lots of tricks available to flat-field images properly and get good catalogues built. If you are used to driving things from the command line you'll feel right at home. If you are used to GUIs with everything the learning curve will be steeper... But read papers on analysing optical CCD images - the http://xxx.lanl.gov/ preprint server gives you searchable access to lots of astro-ph preprints.
Cheers,
Toby Haynes
Anything I post is strictly my own thoughts and doesn't necessarily have anything to do with the opinions of IBM.
For the absolute beginner out there, start off with the naked eye. Go out somewhere dark away from streetlighting (>>20 miles if poss.) and admire the heavens. :-)
:-)
When I was in my early teens, for learning the constellations, I found the Collins Guide to Stars and Planets invaluable. It's got star maps, nothern and southern hemisphere for each month of the year, and brief descriptions of the planets and other main features of the solar system.
When you've learned a few of the constellations and about the types of stars out there, get some binoculars and a tripod stand for them. Magnification doesn't matter as much as diameter of the lenses (ie light collecting power is most important).
Look at things like double stars, the Orion nebula, the Andromeda galaxy.
When you get a bit better at finding your way around, get yourself a newtonian reflecting telescope of at leat 6 inches diameter.
Then, you're away!
Add stepper motors, link to a PC. Put on an SLR camera or a CCD.....
As for software, in my day it was skyglobe, but nowadays xephem is what you want
Join an ammateur astronomy club.
Have fun. Stay up all night watching the silent splendour of the night sky that most people never appreciate.
Good luck
I'm out of my tree just now but please feel free to leave a banana.
The usual Google search turns up several references. If you're too lazy to Google, start here.
Celestia is a free OpenGL space simulator for Linux, Windows, and Mac OS X . . . It's different than XEphem in that it's not an observing tool, but a graphical tour of outer space. In Celestia you can travel to the planets of our solar system, their moons, over 100,000 stars from the HIPPARCOS catalog, and all of known extrasolar planets. And best of all, Celestia is open source, so if something is missing, you can add it yourself.
--Chris
A large set of pointers to open-source astronomy software can be found on the Linux for Astronomy site. Go to the links section to get links to most packages homepages. Linux for Astronomy is at http://www.randomfactory.com/
The Meade Autostar telescopes are great for someone who is wanting to look at the cosmos but isn't sure where to look. You set it up, do some alignment, then select from thousands of different objects to look at. It will automatically locate to that object.
I react to only the most volatile substances.
Oh yeah, they start at $299.
I react to only the most volatile substances.
OK, finally, to get it straight, the Meade ETX-90EC telescope can be found at the Discovery store for $495, but most other places have it for $595. I promise not to reply to myself any more.
I react to only the most volatile substances.
I'm in the same boat as you but slightly further along. I'd always been bleating to my wife about wanting to get into Astronomy so she went out and got me a telescope as a gift. It's only a 60mm Refractor but it does have a decent equatorial mount and eyepieces although I can always buy others since it came with the standard size.
:). So I got a planisphere and a start chart and sat out and learned where stuff was generally and how to find it. Stuff like using Orion to find Procyon and Canopus or using other markers as guides. Just sitting out under the stars and seeing how the sky fits together is as fun as seeing Saturn for the first time.
After checking out all the abvious ones like the Moon, Jupiter and Saturn (now *there's* a buzz) and generally impressing my family I started doing a bit more reading. As pointed out earlier it's no good looking at stuff close-up if you don't know a little more about the big picture. Kind of a "forest for the trees" thing but it's a pretty damn big forest
Don't forget you can also look for other things like satellites and Iridium flares which I've just learnt about.
I've having a look at some of the maths as well. Like how to calculate sunrise/sunset times etc. It's fascinating to see how it all fits together and it's damn cool to plug in a few values and calculate sunset time and then 'Hey presto!' the sun sets at that time. Maths on a real and big scale.
There's oodles of software. Some of the more esoteric stuff like Iridium flares uses some wacky software but some of the general software is great. I can't attest to the X software but an excellent Windows (/me ducks) product is Starry Night from http://www.starrynight.com/. The backyard version has some cool features and isn't so light that you'll outgrow is quickly.
Anyway, have a blast and may your skies always be clear.
For me there's only one set of books that, in addition to being better observing references than anything you'll find out there on CD, really capture what it is to love the night sky. Burnham's Celestial Handbook, published as three huge volumes in updated form in 1983 remains a true classic.
I hardly know where to begin in urging you to own these books. First of all don't be put off by their age. They may not be up to date on all the shiniest new astrophysics, but that's utterly unimportant compared to the huge number of treasures contained within them. The Celestial Handbook is an encyclopedic journey through the deep sky objects visible to an amateur telescope, organized alphabetically by constellation as a compilation of descriptions, observing notes, mythology, finder charts, photos, poetry, orbital diagrams, illustrations, light curves and tables.
If you feel like you've moved beyond the "Welcome to The Milky Way Galaxy" level of popular astronomical literature, these books will fill the gap in abundance. Each chapter starts off with a comprehensive list of objects to be seen in each constellation complete with notes about how they appear in amateur telescopes. After this there is page after page of detailed description about the most significant objects ranging from observing methods to mythology and ancient history. It is a tour guide for the observable universe, taking stops to examine a multitude of clusters, variable stars, supernova remnants, nebula, galaxies, and much more.
Insofar as the astronomy is dated, the effect really isn't very bad. Burnham was an astronomer at Lowell for many decades, and knew what he was on about. This issue is entirely outweighed by the masses of practical advice and genuine wonder to be found on just about every page. The observing experience of a lifetime went into these books.
Burnham was an astronomer by trade, and a poet by inclination. The Celestial Handbook makes this clear from beginning to end. I've owned my copy for almost twenty years now, and I'll never part with it.
Learn the sky. Be willing to travel out to dark skies. This takes AT LEAST a year!
Find and join a local astro club. Find these on the net... many astronerds are just that... nerds. There were more astronomers on the net in the early days...
Get active in the club, go out observing with them, astroheads aways want to show off their hardware, so you can get lots of chances to try before you buy;
Be patient: imaging is hard work, takes a pretty good investment and can become "work" pretty quickly;
Don't be blind to building your own scope with collected parts... sort of like putting together a PC. It's fun, it's entertaining, you know it, you can fix it, you love it. Lots of good groups around the web for this;
Read all the old Sky and Telescopes and ASTRONOMY magazines you can find. Check them out of a local library and read, read and read. Read everything, including the ads;
Don't get sucked in to the idea that "more expensive" is better. You can do some serious science or just have great fun with some of the cheap hardware;
I'm in my 21st year of amateur astronomy and still going strong... it's a blast. See:
My homemade scopes;
My drawings of Mars - many made with a small 4-inch telescope.
Good luck!
First of all, as for binoculars (a very good idea, IMO) they are described by a two number 'code' such as 7x50 or 10x70, where the first number represents the magnification and the second the size of the 'input' lenses (in mm). Surprisingly to most newbies, it's the second number that matters the most. The challenge in seeing many astronomical objects is not in making them bigger, but in making them brighter (there are exceptions, of course).
There's a catch, in that if you make the objective lenses too big without increasing the magnification accordingly you end up throwing a wider beam of light at your eye than can actually fit through your iris. The width of this beam of light is called the 'exit pupil' and you can figure it by dividing the objective size (the second number) by the magnification (the first).
So, for many years, astronomers were advised to get binocs that had this measurement as close as possible to 7mm, that being about as large as young, healthy pupils can get. Any larger and you'd be wasting light, any smaller and your magnification would be higher than optimal, spreading all that light your glass worked so hard to gather over a larger area, and thus lowering the brightness of any one part.
Nowdays, however, more experienced binocular observers than I have determined that some magnification is a good thing to have, too. They suggest different binoculars will show roughly the same amount if the product of the two description numbers is the same. Check the link above for details. I'm not sure I'm convinced, but I know one way to satisfy both criteria- I'll buy binoculars with a traditional exit pupil, but the very biggest one's I can handle.
Which brings us to the other numbers that describe a pair of binoculars. The price, about which no more needs to be said (except perhaps the occasional 'yikes!' form the underpaid sysape), and the weight. Larger binoculars are, of course, heavier. Heavier binoculars are really hard to hold steady enough to see things with when looking up. 7x50's seem to be about the limit for hand holding by most people. Maybe 10X70's if you're Conan. Anything much beyond that and you'll be looking for a photographer's tripod, or a beanbag perched atop a wall, or any of the other myriad gadgets astronomers have cooked up to hold their binoculars steady.
Gee, what a saga. I hope it's usefull to someone. Think I'll ramble about scopes such in another post.
Well I'm what you can call "refractor otaku" and I can say that ANY high-end refractor kicks ass big time. Maybe it's just me but I was always too lazy to really care about mirror colimation and stuff. So my advice is, get yourself a Tak and you'll see. My Sky90 is really cool little scope.
...there's always Jack Horkheimer, the "Star Hustler!"
b-)
:::Horrendous Experiences Make Amusing Anecdotes:::
OK, Spent far too long explaining binoculars upthread, so I'll try to be more concise.
The Meade ETX telescopes mentioned above are what's known as go-to scopes. They use a computer, a pair of motors, and some reasonably simple initialization steps to find objects for you at at the push of a button, and to move the scope to keep it in view as the earth turns beneath your feet. This largely obviates the need to learn the sky, which is both good and bad. Good, because it gets you clear over the first hurdle upon which many beginners stumble. Bad because much of the money you've spent goes to pay for the computer and drives, rather than the optics, so the views you'll get will be somewhat poorer than comparably priced 'scopes of similar design.
The other extreme is the 'Dobsonian', elegantly planned scopes with bog-simple structures and mechanics, often mostly of cardboard and plywood, so that every available dime can be spent on the parts that actually harvest photons. Amazing views for the dollar, but you'll have to learn to find things yourself, and to keep nudging the scope along to keep them in view. Still, this is what most experienced amateurs of my acquaintance use and recommend, and I strongly suspect they're right.
What almost nobody seems to recommend anymore is the traditionally mounted small scope. These use a mechanical arrangement to allow the scope to follow objects across the sky, but they don't locate objects for you, and they have to be carefully aligned each time they're used if you want to take full advantage of the tracking. For certain applications, big, smooth, bulletproof (and often permanently installed) versions of these sorts of scope are perfect. But the one's you'll find in the price range in the article are typically flimsy, shaky, and really tough to use.
If you do decide to go whole hog and decide to both buy a telescope and start learning the sky, let me make two recommendations. The first is a 'zero-power finder', an inexpensive gadget like a head's up display for a telescope, or the red dot sight from a bb-gun (in fact, that's exactly what some of them are). It displays a glowing circle or dot that actually appears to be out there among the stars, at exactly the spot where the 'scope is pointed. There are other ways of finding things, but this is one of the easiest,
The other is a book called 'The Year Round Messier Marathon Field Guide' by Harvard Pennington. It shows maps for finding a hundred or so of the most popular observing targets (the Messier objects), such a way that slightly more experienced observers can find them all in one night (the 'Marathon'). The maps are marked up with simple geometrical constructions that make it clear that, for example, to find object a you should put the circle just about two thirds of the way along the line from stars b to c, maybe little skosh off in the direction of d. This was the book that finally got me over the hurdle from knowing how to find a handfull of things to knowing I can find whatever I want to badly enough, just by knowing how to read a star map in a certain way.
And even if the hobby turns out, in the end, not to be for you, let me recommend Sky and Telescope magazine. Observing's not everyone's cup of tea, but there's no better way for _anyone_ to keep up on the amazing discoveries that seem to be occurring almost weekly now than in S&T's clear and complete pages.
Finally, let me second (third, and fourth) the suggestion that you find and join your local astronomy club. There's a reason these thrive when most similar organizations are withering. All the info you can get from Slashdot is great, but it doesn't hold a candle to actually peering through other people's scopes before you choose your own, or asking navigation questions of someone who can stand beside you and point. Besides, nothing improves an amazing view like sharing it, and nothing can salvage a cloudy evening as well as an hour or two of coffee and astro-gab before calling it a night and heading home. Nope, not even Slash (though tonight, Slash is warmer)
HTH,
Chris
Best foto's (imho) can be found, (with prof. comment) on: http://www.star.ucl.ac.uk/~apod/apod/astropix.html
No telesope can beat that.
Specially if you live in an area where in *NEVER* gets dark.