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What Objects To Focus On For School Astronomy?
IceDiver writes "I am a teacher in a small rural school. My Grade 9 students are doing a unit on astronomy this spring. I have access to a 4" telescope, and would like to give my students a chance to use it. We will probably only be able to attempt observations on a couple of nights because of weather and time restrictions. I am as new to telescope use as my students, so I have no idea what objects would look good through a 4" lens. What observations should I attempt to have my students make? In other words, how can I make best use of my limited equipment and time to give my students the best experience possible?"
The moon. You can actually look at it without going blind.
Free Martian Whores!
Jupiter and Saturn too. You can even see some of their moons.
For justice, we must go to Don Corleone
I'd suggest objects that are very easy to find, so the students don't spend the whole time searching for them.
Jupiter, Saturn, Mars, Venus, M31 (Andromeda galaxy), Orion Nebula (M42) are a good start.
A great book for beginners is Turn Left at Orion, by Guy Consolmagno
http://www.amazon.co.uk/Turn-Left-Orion-Hundred-Telescope/dp/0521781906
Planets and clusters are probably the easiest objects to find with a 4" telescope (same size as mine). Planets are really easy to find since you can usually spot them, and you should be able to see some detail- moons around Jupiter, and Saturn's rings.
Clusters (globular, open, etc) may be a bit harder to find and harder to see, but some of them are impressive with even a 4" telescope. The Messier objects shouldn't be too hard to find with a star chart.
Different things are visible at different times, although a four inch telescope is really only going to be able to see the the brightest objects. A little better than binoculars, but surprisingly little better after you account for the perception boost binoculars get by letting you use both eyes.
If you're talking about a nearby observation opportunity, then let me recommend Sky & Telescope - At a Glance and Human Spaceflight Realtime Data as sources of interesting things to look for. You can also nearly always find a satellite or two around dusk, if you know where to look. Nasa has some pages about that as well.
Make sure you have some information to talk about about everything you plan to look at, since most of the class will be standing around the telescope rather than actually looking through it at any given time.
Can you be Even More Awesome?!
You didn't mention the location of your school (probably wisely); however, it would be useful to know at least the vague region in which you live, as it impacts what's visible at different times of the year.
The moon, Venus, and Mars are good places to start. NASA has a "Near-Earth Object" program (http://neo.jpl.nasa.gov/) that may be of interest to you.
Also, while man-made objects aren't necessarily directly related to astronomy, the International Space Station is also quite visible with the naked eye; I'm sure a telescope would make the observation much better. Again, this depends on your location and when the ISS will be visible there.
"You will pay for your lack of vision..." - Emperor Palpatine to Ray Charles
The Moon. Jupiter and its moons. Saturn. Venus. The Orion Nebula. The Andromeda Galaxy.
And get out there and look at the dramatic and easy stuff. Jupiter and its moons is really cool to watch. And you just can't go wrong with the moon. All of the things I listed above should be easy to find with a small telescope. Looking for much more is going to be frustrating and boring for a group of students. Looking at stars is going to be very boring (stars look like points of light, even with the best telescopes). Go grab a copy of http://www.stellarium.org/ to help you find things and you should be good to go.
-Erik -- --This message was written using 73% post-consumer electrons--
Why ask this hear when there are numerous places where you'll get better answers. Try www.cloudynights.com.
Here is a good beginners guide to finding objects and telescope use: http://www.rocketroberts.com/astro/first.htm
With a 4"'er, you're not going to get any detail out of Jupiter or Saturn. No cloud bands on Jupiter -- just the moons as points of light. Saturn will look like this or this if you're lucky.
But the moon looks great at any magnification.
Kneel Before Christ!
http://spaceflight.nasa.gov/realdata/sightings/index.html
You save only 59 seconds over 8 miles by going 75 instead of 65. Do you really have to pass that guy? Do the Math!
Download Stellarium for free and explore with your PC.
Good source of free starmaps: skymaps.com
Here are some fairly easy targets off the top of my head...
Moon: Choose a night when the Moon is not full -- have a look at the terminator (the boundary between the dark and light parts). You might be surprised at how those craters and hills seem to pop out at you.
Mars: Mars is near Opposition and should look pretty good -- you might even be able to see a white spot at one of the poles -- that's the polar ice cap.
Other Planets: Saturn, Jupiter, Venus, and Mercury are usually pretty easy to find. See a current starmap for times and locations. (Saturn will rock your world.)
Albireo: The head of Cygnus the Swan is a double star -- one yellow, one blue. Striking and easy to find.
The Ring Nebula: In Lyra, almost centered between two of the stars (find yourself a star map for a visual). It's faint, so you'll want to be away from city lights, but a small telescope should barely see it. It will look like a dim gray ring. Show the kids that, then show them the HST picture for comparison.
The Milky Way: Billions that faint gray swath turns into billions of stars when viewed through a telescope (even a small one).
The Neighborhood of Scorpius: There are several interesting things to see in Scorpius. Globular clusters, etc. Get a starmap and point the scope(s) South!
Dress warm and have fun out there!
--
Ron Proctor
Production Coordinator
Ott Planetarium - Weber State University
weber.edu/planetarium
The moon, particularly when it's NOT full, as there is more detail to see when it's not full. Someone mentioned Jupiter and it's moons. Observe them over several nights, have your students sketch what they see, discuss why the moons are in different positions each night/hour. Get a copy of "Skyways" from the Royal AStronomical Society of Canada - it's a resource for teachers (http://www.rasc.ca/publications/index.shtml). The Pleiades star cluster is always beautiful. Saturn will be high in the south east and is always nice even in a small telescope. Mars will be high in Cancer next to the Bee-hive cluster. Both are wonderful small-scope objects and will be very close together. The three bright galaxies in Leo, "The Leo Triplet" (http://en.wikipedia.org/wiki/Leo_Triplet) will all fit in a field of view nicely. Good luck!
Hi, I help run an astronomy group (San Diego Astronomy Association) and I think I can help you out - feel free to contact me directly if you have questions.
:)
Right now I would recommend showing off:
The Pleiades (M45) - http://en.wikipedia.org/wiki/Pleiades_(star_cluster)
The Great Orion Nebula (M42) - http://en.wikipedia.org/wiki/Orion_Nebula
The Andromeda Galaxy (M31) - http://en.wikipedia.org/wiki/Andromeda_galaxy
You can also check out the planets - right now Mars is pretty close and bright, but it isn't much to look at through a 4" telescope. You can show off Saturn, but it doesn't rise until kind of late. You should be able to see the rings, but right now they are edge-on.
Depending on where you are located, you may also be able to check out some smaller galaxies and nebula. Also, depending on where you are located, get in contact with an astronomy group and see if you can visit a local amateur observatory. We have a site about an hour from down town San Diego where we have a 22" telescope available for public viewing once a month and we also have public events held almost weekly where we bring telescopes generally around 10" in size (I bring my 16" on clear nights).
Others have joked about using your telescope to point at the Sun - obviously don't do it. Even pointing the scope at the Sun will permanently destroy eyepieces and coatings on optics - and if you happen to look through it, say good bye to your vision. Permanently. However, if you can get yourself a solar filter to put over the telescope, you can safely observe the Sun - which is pretty interesting. You should be able to see sun spots and perhaps prominences with the right kind of filter.
Good luck, and clear skies!
-Bill
Link to general visibility -- http://homepage.ntlworld.com/mjpowell/Astro/Naked-Eye-Planets/Naked-Eye-Planets.htm
Your geographical location doesn't matter too much in spring, as you'll get plenty of viewing along the ecliptic.
I think the linked site is for northern hemisphere. Hope your kids understand ecliptic before you're done.
More links like it? google terms: planets visibility 2010
Although it isn't actually looking at the objects with your own telescope, all of the data that the Hubble Space Telescope creates is free to the public. To use the data you will need a copy of Adobe Photoshop, but once you have that it can be great fun to create the same sort of images you see from the Hubble Heritage site. To use the data (that you get in fits format) in Photoshop, you need to download the "Fits Liberator" from the http://www.spacetelescope.org/ site (check the projects tab). You can then get the data from http://archive.stsci.edu/hst/search.php (you will have to create an account).
No matter where you go, there you are. So Enjoy it.
Venus will become an evening star in the next few months. If your observations are over a few weeks, it would be an excellent evening target as it will go through its phases, much like our own moon does. If the observations are around twilight, you can even have them attempt to see Venus while the sun is still up by looking in the same part of the sky when the sun is up. It gets harder with age(sigh) but I remember easily being able to do it when I was around the age of grade 9.
The Moon focus on the shadow line, or a time when its around 1 week bfore a full moon, as the terminator(shadow) will show excellent surface relief of features.
Jupiter will be probably be only an early morning target during that time, so thats probably out.
Saturn isnt going to be a very good target, other than to show it as a planet, because it is in the part of its orbit where the rings are tilted almost edge on to earth.
Globular Clusters M13 in Hercules would be an excellent target.
Planetary Nebula The 'ring nebula' in the constellation Lyra will be a excellent target for evening viewing, if its late enough, as from most locations in the US it appears almost at the zenith
Double Stars Even through a 4" scope you can see some amazing color contrasts. Albireo in the constellation Cygnus is one of the best, with one red, one blue star. Also, you can go in to some detail about the different types of telescopes, and their functions.
But most importantly, focus on the history of Astronomy itself. There is a rich history over thousands of years of astronomers that have taken us all the way to where we are now, and we wouldnt be here without those giants of the past; Gallileo Gallelie, Nikolas Copernicus, Tycho Brahe, Charles Messier(hes the 'M' in all those objects...M13, M31, etc), Edwin Hubble, Edmund Halley.
I envy you. Have Fun!
In grade 10 the most impressive viewing I had was a daytime viewing of Jupiter. We looked at multiple planets during the day, it was very cool. It was an elective astronomy class though, so everyone there was very interested.
The moon is good, but planets, depending on what is in the sky, would also be very cool. You can really see that Mars is red.
Show them whatever inner planets are visible this time of year and they'll probably never forget it. Venus, Mars and Jupiter are awesome... and show them how you found them in the sky.
Why not let your students choose some/all of the targets, subject to final vetting (or pre-screening) by you? In this way they gain a feeling of ownership over the process and generally become more invested in the subject matter. You could even point them to Stellarium for free home planetarium software to plan their observations.
Whatever you decide to observe, your students will get more out of it if they are actively involved -- i.e., no passive observing. If you have several nights, you could look at Jupiter each night and have them sketch the arrangement of the moons (c.f. Galilei 1610). If you have a solar filter, you could do the same thing with sunspots (if any are visible). Venus, Mars, or Saturn's rings may be attractive targets, depending on what you want to do with the observations.
Finally, there are additional astronomy education resources at the Astronomy Education Review, a free online journal.
My advice is to focus mostly on the sky rather than the telescope. You don't want to have "telescope class".
Invite students to bring binoculars. Find and identify all the constellations you can. They're not just for astrology, they're a great way to orient yourself to the sky.
Plus they're interesting and historical and you can see them with the naked eye. If you have 2 nights, find a planet on the first night and note it's position. On your next night out you can note how it "wandered". "Planet" being greek for "wanderer". Be sure to check out the Big Dipper. One it's stars is an optical binary as well as a telescopic binary. There's a nice little story to be told about ancient people using it to test eyesight. It's a great thing to look at with the naked eye, binoculars, and then the telescope, showing how each tool works relative to the other. Since most of the kids won't have telescopes at home, these are great lessons in how neat astronomy is with just your eyes and/or binoculars. They don't need a telescope to be interested.
If you or somebody in your class has an iphone there are great astronomy apps. StarMap and Distant Suns are both very good and offer free versions that work great in the field.
Also, blankets and tarps are a good thing to bring along. Looking at the sky with the naked eye or binoculars is much more enjoyable lying on one's back. Craning necks is a good way to lose interest fast.
Have Fun!!
Operator, give me the number for 911!
No doubt, the Moon should be target number one. But not the full moon -- the full moon is fairly uninteresting and you see no detail.
The best times, IMO, are around first and third quarters, where the terminator shows off the actual surface shape. Even with a 4" scope you'll be able to get much more understanding and visual interest during these times from the Moon's surface.
I highly suggest taking the scope out prior to this unit to become familiar with the basics and this particular scope's quirks, if you are not already. Nothing is worse for group observational astronomy than waiting around for somebody else to screw with the scope.
Do NOT look directly at the sun through the telescope, of course. Instead, you use the telescope as a projector.
It takes a minute or two to aim: the trick is to use the shadow from the telescope to aim. When the shadow is smallest, you're pointing the right way.)
There are lots of web sites describing how to do it, such as this one. (I've never used the extra collar like they describe, but it probably wouldn't hurt.)
It also has the advantage that it's something a small group of people can enjoy at once.
At night, if it's reasonably dark at all, I'd recommend the moon (always easy to see. Use a moon filter, which probably came with your telescope).
Also, you should be able to see the Orion Nebula as a wide fuzzy patch. I've seen the banding of Jupiter, as well as its moons, in my 3.5" telescope, though I wasn't able to find the Red Spot, and the rings of Saturn.
Definitely get a software star chart (there are free ones available online) and a red filter for your flashlight so you don't lose night vision. It makes a surprisingly large difference.
If the masses can keep you down, you're not the Ubermensch.
You may laugh, but as a youth, I ignored the warnings and watched a solar eclipse without protection. To this day I have a small area in my visual field that is permanently damaged. That was about 32 years ago.
Little girls, like butterflies, need no excuse. -- L. Long
Another vote for Jupiter here, plus take viewings over a couple of nights and the students will be able to track the changing positions of the 4 largest moons and Jupiters position against the background stars.
These comments are my personal opinions and do not necessarily reflect the opinions of the other voices in my head.
Unrelated to the real topic, but regarding your signature, you realize that isn't helping your case? If I save a minute every 8 miles traveled I'm saving almost an hour off my 400 mile trip, seems like a good idea to me.
I know its not a one night job, but maybe some visual observations of variables for extra credit thru the entire year?
Yeah it is a bit late to start now:
You'll be spending alot of time at the AAVSO website, may as well start here:
http://www.aavso.org/publications/manual/
Basically, you learn two skills, star hopping from beta cep to tau cep, and then you compare the brightness of tau cep with its neighbors which have fixed, known magnitudes to estimate tau cep magnitude today.
http://www.aavso.org/images/starhopping.gif
It has the virtue of being free, if nothing else.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
I had looked at the moon forever with the naked eye, and a few times through a couple of lenses, including a backyard telescope. Then, because there was going to be an occultation, I had a chance to look at Jupiter through a pair of binocs. I was blown away that something that close had that much structure -- you could see just scads of moons!
To instil a sense of Science, give the kids tools that they can use well beyond your classes. To this day, when I see Orion in the night sky, he seems like an old friend. When I see Mars waxing and waning, it helps me keep track of time through its two year cycle. Have them look at impressive things, but make sure you give them the tools to find the same objects with their naked eyes. Unless these kids become astronomers, they'll spend at most a few hours behind glass, but will have the rest of their lives to look up at the night sky with their eyes.
One of the coolest things I've learned as a closet amateur astronomer is that the dark side of the moon is illuminated by backwash from the earth, or earthshine. OK, that makes sense if you think about it. But this fact was known almost 100 years ago, and we have a nearly complete record of the brightness of the dark side of the moon since then. That record is important because earthshine is directly related to the amount of terrestrial cloud cover, and that is related to climate. I wish I had known that as a kid, because I'd often wondered why you could see the dark side of the moon better (brighter) on some nights than on others.
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
NASA has a website for educators:
http://www.nasa.gov/audience/foreducators/index.html
Most missions have a public outreach person who will send materials to teachers for use in their classroom.
And for those joking about looking at the sun, see :
http://sohowww.nascom.nasa.gov/classroom/for_students.html
http://stereo.gsfc.nasa.gov/classroom/classroom.shtml
Build it, and they will come^Hplain.
I remember looking at the moon around that time and noticing the bright spot next to it. I don't know much about the night sky but even I noticed that that was unusual. I downloaded Stellarium to find out what that bright "star" was. The planets are interesting because they move across the sky. The stars are interesting because they show Earth's own motion. The moon is interesting because it's close enough to see details on another celestial body.
I doubt that photo is unedited. It's probably a HDR reconstruction. Even mostly behind the clouds, the moon should be so bright as to be overexposed if the Galilean moons are also clear and visible in frame.
Kneel Before Christ!
Err, you guys know they make solar filters for telescopes? I used to watch sunspots and solar eclipses all the time. My eye sight is still perfect (except for presbyopia now that I'm getting old - hard to focus on up close items).
This is incorrect. Saturn's rings are clearly visible in my 2.5" telescope. Banding is visible on Jupiter if the moon is down and seeing is good. Also, the brightest moons will be clearly visible for both planets.
Many people think that the best time to look at the moon is when it is full. This is the worst time to use a telescope other than when it is cloudy. It is washed out and flat. Try with no more than 1/2 moon then you can see the rough surface due to the shadows. It is worth looking at when full but far better otherwise
The next most important thing is to practice where you will be setting up. You need to be familiar with the sky. Find the planets beforehand so you can point out the ones that are up and some of the major constellations. Remember planets move around a bit as well. If you are some where that is humid, it can be helpful to have a bright spotlight. You can point out locations in the sky. Show them where the Zodiac is (the constellations that the sun rises in and the planets move through). Jupiter and Saturn are also good. If clear and dark enough you can show them the milky way.
Lastly I would hope you have a plan of what to say. I talk about Galileo and the arguments that were being made about the sky before the telescope was pointed at the sky. The moon was thought to be basically featureless and round. Point out the moon and ask them to look at it for a minute. No one had seen a much better view than you are seeing now.
Someone (probably Galileo) first pointed a telescope at the moon and then saw this Prepare for a gasp when they look.
Everything went around the earth, then Jupiter, “see the little dots they move around” and you can see this from night to night in a pattern
One more thing. if your scope does not have a motor mount you will need to frequently move it to make up for the turning of the earth. Also people will bump it and the next person will see nothing but black. This is tricky as they will not tell you if they do not see anything.
Jupiter and its moons are important because of Galileo, and Galileo used Jupiter and moons as an analogy for the Copernican helio-centric model. Venus can also serve that purpose if it is showing a crescent -- the phases of Venus were further support for Copernicus according to Galileao.
Next, point out objects such as the Big Dipper. It actually is a star cluster, only we are too close to it to notice. Work your way out to the Pleiades and the Bee Hive. You can point out that the Pleiades appear on the hood ornament of a popular Japanese car as "Subaru" is the name for the Pleiades in Japan.
Depending on season, try the Orion Nebula as an active formation region of a star cluster, some of the more distance "galactic" star clusters in the Milky Way. Revert to the naked eye and point out the Milky Way (if able depending on light pollution and weather) and the "dark rifts" in the Milky Way (those are not the absence of stars, rather they are the presence of dust -- the heavy elements out of which you and I are made out of and where are heavy elements came from).
Next, try for a globular cluster such as M-13. Tell the story of Harlow Shapley and the discovery that the center of the Milky Way is in Sagittarius instead of us being in the center.
Finally, wrap up with a view of M-31, and explain how Edwin Hubble discovered Cephiad variables in it and discovered it to be remote. Point out Polaris (the North Star) and explain that it is a Cephiad -- that it is a reasonably distant star, but we see it because of its high luminosity. Tell the story of Hubble's discovery of the "spirals" as being "island universes" like our Milky Way, red shift, and what I call the "Copernican Revolution of the 20th Century", where M-31 was the stepping stone to finding out how freakin' large the Universe is and how we are such a small speck in it.
Also, moderate expectations of what they are going to see. Explain that large telescopes taking long photographic or CCD time exposures can show much more dramatic views of the same objects, but they are looking at what they see in those famous pictures with their own eyeball, first hand, through your telescope. Also give them a primer on averted vision on how to see faint objects. Finally, explain that through the telescope what they are seeing of M-31 is mainly the central core, and that M-31 is a much vaster and fainter object that extends well beyond the telescope field.
I used my binoculars to go spotting at Jupiter a while back after this image... Outstanding picture. ...a sense of being inside a solar system than any of those things.
About ten years ago, I had a 4" Newtonian telescope, and being a fairly constant reader of Sky & Telescope Magazine, I knew that the Moon was to occult Uranus at a specific date and time. So I pointed my telescope in the right direction and, sure enough, this perfect little green sphere rose from the mountains of the Moon, definitely one of those "wow!" moments.
At other times, I did also manage to "snag" a couple of the LINEAR comets.
So my best advice for the budding amateur astronomer is to buy Sky & Telescope Magazine or visit http://www.skyandtelescope.com/ to get monthly tips of celestial event watching.
A friend of mine owns several more serious telescopes, in the 10" - 18" inch range, and what's kept him up at night during the past year is the challenge of "capturing" binary star systems, here's the drill:
1. Find your target binary in a star atlas. There's tons of them. Some of them are even triple or quadruple star systems.
2. Point the telescope in the general direction, find your bearings and lock on target. This might take a while.
3. Increase magnification by changing lenses, until the lesser magnitude companion star pops out. Mission accomplished.
4. Go for a more difficult (lesser magnitude) system next time around, thereby honing your skills.
Happy hunting!
Lil' Thindime, lilting a lacrimose lament, krashes the kwaint konfines of Kokonino Kounty
That is not true. In a 4" telescope with decent magnification 100-150x you should clearly see all four of the Galilean moons as well as two bands across Jupiter. Now the problem with Jupiter is that it's in Superior Conjunction with the Sun (i.e. you can't see it). However you can see Saturn and Mars in the evening sky. Mars you won't see much, but Saturn will be the thing the kids remember more than anything else. Visit www.skymaps.org for a good, free star chart to use with the kids. Depending on when you observe there are many great, bright objects in the sky. Here are a couple you can google: M42, M45, M31, Double Cluster, M13, Castor. This list is very easy to find even in fairly light polluted skies with little difficulty. Hint: Try to find these on a night by yourself before you show the kids. It will be less stressful and make your life easier. For more help visit cloudynights.com. It's a great amateur astronomy forum to learn about the night sky and ask questions. Good luck and have fun.
With my 70mm (2.75") telescope, I can see Saturn's rings more clearly than either of those photos, and 2 cloud bands on Jupiter. What'll influence how well you can see them more than the diameter of your lens is the focal lengths of your telescope and eyepiece and the quality of the lenses. My scope has a 600mm focal length, so with my 9mm eyepiece, I get about 67x magnification (600/9). I have a 2x barlow, which makes the image bigger, but it's not very good quality, so it blurs it so much that it's not worth using.
I'd recommend Jupiter, Saturn, the Orion Nebula and the Pleiades. They're all super easy to locate once you know where to look (you can see them all with the naked eye...just not very well!). Also, definitely get a good look at the moon. It's more interesting when it's not full, since that gives you more relief. Unless you have a filter, with a 4" main lens, the moon is going to be pretty bright.
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Fully agree: Jupiter, Saturn, the Moon.
Suggest starting with Jupiter, with focus on its moons and (if you are lucky with your choice of nights) changes in their positions relative to Jupiter. Tie this in with Galileo as the prototypical scientific mind questioning the authorities of his day. (Remember that Galileo came to recognize the Sun's central position in the Solar System after watching the dance of Jupiter's moons).
Also Saturn. With luck the rings will be evident.
Save the Moon for last. Nights that best for Jupiter and Saturn are going to be moon-less nights, but OTOH you can do more with the Moon with 10x binoculars than with a 4 inch telescope: you need the wider field of view to figure out what you are looking at.
You can probably find an amateur astronomer in your town who would be interested in helping with a project like this. In fact this kind of thing could easily become the focus for a series of star parties.
Will