Our second and final meeting at the Boy Scout Merit Badge College is coming up this Saturday. We’ve had some great nights for stargazing (and a few not so good nights) so I hope you’ve been practicing.
This week you should check all of the work you’ve completed. Make sure your name is on every page, all requirements are numbered and try to put them in order. I’ll try to get through everyone’s materials and get them back to you as soon as I can.
When we meet, I’ll take everyone into the dome one more time and go over all of the stars and constellations. After that we’ll go back out to the table where you can finish up any requirements you need a little more information for. I’ll have my collection of Astronomy and space books, if there’s something you just haven’t been able to find. While people are getting things together,
I’ll be taking two Scouts at a time back into the dome for the star and constellation test. One Scout will get the pointer and identify 10 constellations (four from the Zodiac) and 8 stars. The other will stay in the entry tube to get dark adapted. After the first Scout has identified his stars and constellations ( or given up ), he’ll leave the dome and another Scout will come into the entry tube to get dark adapted while the Scout who was in the tube takes his test.
My wife will be there to help anyone who needs a little assistance. She’s a Girl Scout Astronomy Trainer so she can answer most of the questions you might come up with.
If you don’t finish all of the requirements now, you’ll be able to send them along to me as you complete them. This is a fairly difficult badge to earn and our time together is fairly short, but most of the requirements are things you can do on your own. Don’t give up. I’m always just an email away when you have a question.
If you don’t pass the constellation and star test, things get a little complicated. We won’t have a space to set up my dome when the college is not in session, so you’ll have to take the test under the real sky or wait until next year and finish the test at the 2018 college. If you want to take the test under the real sky, remember the stars change every season, so the constellations and stars you see in May won’t be the same ones we worked on in March.
Deciding if a planet is visible or not in the evening (5b) seems to be a problem sometimes. There are a couple of ways to do this. One is to go to the library or pick up your own copy of the Old Farmers Almanac. Another is to use Stellarium and advance time a month at a time. A third ways is to use the Sky & Telescope Almanac.
Let’s think about what you need to know to decide. If you’re using the Sky & Telescope almanac (you need to register for the website to use this) to determine which planets are visible, they provide the information, but you need to do some thinking. The first thing that’s important is what time does the Sun set. The Sun sets at different times all year long and the last column on the first row of the almanac shows when the Sun sets. If a planet sets before or just after the Sun sets, you won’t be able to see it.
Look in the sixth column and you’ll see Mercury sets at around 8:00 pm so you’ll see it in the evening. Venus sets around 5:30 pm. You won’t see it in the evening right now. What about in the morning?
That method will work for most planets, but you’ll need to think a little harder for some of the others. Let’s look at Mars. It sets at around 9:00 pm. That one is easy, 9:00 pm is definitely in the evening, Mars is visible. Jupiter rises now at around 6:45 pm and doesn’t set until after 6:00 am, it’s visible all night. Saturn doesn’t rise until after 12:00 am and it sets in the middle of the morning. Now 12:00 am is the late for me, so that puts Saturn in the sky only in the morning.
I’ve just done the month of March for you. Now you need to start the Almanac (remember to check Daylight Savings Time), advance the +1Week button a couple of times to see what’s up in April. Advance again for each month and fill in your table (you are making a table aren’t you?) and you’ll know when you can see the planets all year long.
One of the hardest parts of the Astronomy Merit Badge is identifying at least ten constellations (requirement 4), four of them in the zodiac, and eight conspicuous stars. Here is a list of most prominent constellations and stars, which are visible in the night sky now. This is the list you should try to learn to identify for the test.
- Ursa Major
- Ursa Minor
- Canus Major
- Canus Minor
You don’t have to learn all of them (see the book), but if you know all of them it will make it easier to take the test. One way to learn them is by using a computer planetarium program. One of my favorite free programs is Stellarium. It’s available in Windows, Mac and Linux versions so download it (with your parents permission of course) and play around with it for a while, to get a hang of how it works.
If you’re using another program adjust what you do to the program you’re using.
First thing is to set your location. If you’re using Stellarium there will be a little tool bar on the lower left side of your screen and one of the tools is a little wrench. Click on it to open the set up box. Click on the location tab and you will find several options, but the ones we’re interested in are latitude and longitude.
Do you know yours? If you don’t you can go here to find it: http://www.zipinfo.com/search/zipcode.htm . To check latitude and longitude just enter your zip code. This will be your local post office as your observation point which is close enough for us. Enter your coordinates by using the little up and down arrows next to lat. and long. in Stellarium and click save, so you always start out looking at the sky the way it will in your back yard.
Now click on the Date & Time tab and check to make sure the current date and time are set. If they are incorrect, your computer may have the wrong date set so check your computer’s clock. If you want to play with the landscapes, go for it, but Guerens (the skyline you get when you first start the program) seems to be the best choice for keeping the screen fairly clean and still give us a reference for where the horizon is. Close the set up screen and now we can take a look at the sky.
If it is already night time you’re all set, if it’s day time you need to speed time up a little. Click the fast forward (>>) on the lower right of the screen two or three times. Don’t get carried away or time will really fly. When the sky gets dark hit the play (>) and time will slow down to real time. Now you should see a nice clear night sky and a few stars. If you have a scrolling mouse, try scrolling your view in and out. If you don’t have a scrolling mouse use the page up and page down keys. Too much ground, too few stars? Left click anywhere on the screen and drag your view up or down. You can also drag left and right to look to the East, West, North or South. Play around with this for a while until you get used to it.
If you can find Mars ( it will be low in the West at around 8:00 pm ), click on it and hit your space bar. What happens? Now try scrolling or using the page up and down keys. You can do this with any objects that could be seen with a telescope, I’ll give you some things to look for on another day.
Now to start learning the constellations and star names. Try playing with the three controls on the left end of the control bar. By turning these on and off and learning the star patterns behind the graphics, you should be able to start learning the constellations.
If you are using another desktop planetarium and having trouble, you can email me with your questions as I have several other programs and I should be able to help out. When it’s clear at night go out right after sunset and see if you can apply what you’ve learned.
If you have any problems or questions, send them along.