Re: Astronomy C
Posted: May 13th, 2013, 7:06 pm
Thanks AlphaTauri!
@JCicc that was a really good test - learned some really weird things.
@JCicc that was a really good test - learned some really weird things.
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Re: Astronomy C
Posted: May 22nd, 2013, 7:41 pm
What are likely topics for next year?
Re: Astronomy C
Posted: May 22nd, 2013, 7:49 pm
I believe it is Variable Stars (all kinds).
The nationals test, again, was very nice. I felt that the test stressed a lot of wavelength identification, which, combined with the fact that they altered the coloring scheme on many of the images (from DS9?), really annoyed me. There was also a sound-speed calculation question, which I foolishly spent a long time on. I blanked out during the test
. My partner kinda carried, but since the test was so long, he only got through about half, so we got 9th. Rather disappointing since we were going for top 3 but we'll be back next year 
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The nationals test, again, was very nice. I felt that the test stressed a lot of wavelength identification, which, combined with the fact that they altered the coloring scheme on many of the images (from DS9?), really annoyed me. There was also a sound-speed calculation question, which I foolishly spent a long time on. I blanked out during the test
. My partner kinda carried, but since the test was so long, he only got through about half, so we got 9th. Rather disappointing since we were going for top 3 but we'll be back next year .Re: Astronomy C
Posted: May 23rd, 2013, 12:47 pm
Nationals exam is up: http://www.aavso.org/science-olympiad-2013
Re: Astronomy C
Posted: June 2nd, 2013, 2:13 pm
Look at the SoCal 2012 Astro Test. Derivatives appear on the first page...but from what I gather, you don't need to know what derivatives are, but you use the table of values given to calculate it.AlphaTauri wrote:syo_astro wrote:But for what we do, the Astronomy C event, you will almost, if never (but I like to say nothing is impossible even if it's very very unlikely) need calculus. Ever. Physics helps for...a few problems? Maybe? But you certainly don't NEED it. I did the event last year, and I managed to do basically all the math between my partner and me, despite my partner being in physics.
So yeah, really if you just put in the time and work you can definitely do fine without it. I am pretty sure others on here can confirm they did the event without being in physics or knowing calculus.
SO events tend to avoid calc in general, and while there is a LOT of calc in actual astrophysics, there's really none required for the event. The physics that you encounter in astro is for the most part, completely different from what you see in physics class (with the exception of the occasional question involving things like escape velocity or Newton's Law of Universal Gravitation, but those can be easily researched online), so honestly, a physics class wouldn't help that much anyway.Luo wrote:I've never seen a Science Olympiad Astronomy question that requires knowledge of calculus. As for physics, you definitely need to know certain astrophysics concepts, such as Kepler's Laws and the physics behind star formation/evolution. It's not necessary to take a physics class, though, to do the event.
I did astro for two years without having taken calc or anything beyond a very rudimentary sixth-grade physics class and I did perfectly fine, so I'm sure you'll be fine without it as well. :]
But how on earth do you calculate the Chandrasekhar limit? (that was one of the questions)
http://www.aavso.org/sites/default/file ... 202012.pdf
Re: Astronomy C
Posted: June 2nd, 2013, 2:25 pm
The equation for the maximum mass (in solar masses) of a star from this model is given in the question. All information is given, except for the ionization fraction, which is asked about in the previous question (#3). I would assume that is a value that is expected to just be known for this event? I have no knowledge of the ionization fraction of a White Dwarf though.Crazy Puny Man wrote:Look at the SoCal 2012 Astro Test. Derivatives appear on the first page...but from what I gather, you don't need to know what derivatives are, but you use the table of values given to calculate it.
But how on earth do you calculate the Chandrasekhar limit? (that was one of the questions)
http://www.aavso.org/sites/default/file ... 202012.pdf
Re: Astronomy C
Posted: June 2nd, 2013, 2:57 pm
Right...I didn't exactly realize that was the equation I had to use... 
Re: Astronomy C
Posted: June 2nd, 2013, 3:09 pm
I don't know anything about ionization fractions either, but since the options for ionization fraction of a white dwarf are given as 0 or 1, you could figure out the correct answer for question #3 by trying both possibilities in question #4 and seeing which one produces a reasonable answer. Using an ionization fraction of 1 produces a Chandrasekhar limit of 5.828 solar masses (which is not in the ballpark of the accepted value), while using an ionization fraction of 0 produces a Chandrasekhar limit of 1.457 solar masses (which is in the ballpark of the accepted value), which would lead one to surmise that the correct answer for question #3 is 0.pjgscioisamazing wrote:All information is given, except for the ionization fraction, which is asked about in the previous question (#3). I would assume that is a value that is expected to just be known for this event? I have no knowledge of the ionization fraction of a White Dwarf though.
Re: Astronomy C
Posted: June 2nd, 2013, 3:12 pm
Edit: Luo got it covered 
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.Re: Astronomy C
Posted: June 2nd, 2013, 3:15 pm
Nevermind then. Dumb question.