Page 12 of 14

Re: Astronomy

Posted: March 19th, 2009, 4:57 am
by jtolley
[quote="EASTstroudsburg13"]
I couldn't find the specific fourmula for apparent/absolute magnitude.[quote]

Are you stating that you don't want merely ratio formulas which compare such things like two star's luminosity's to their distances...?

Well, there are several different formulas that you can use to find apparent magnitude and absolute magnitude without having to rely on information about another star.

Of course, there is the one we should ALL know:

m - M = 5log(d/10), where d is in parsecs. So if you know distance and a type of magnitude, you can find the other magnitude.

Now, SPECIFIC formulas for magnitude are a little weirder. First, there is this one relating absolute magnitude to period (in days):

M = -2.81log(P) - 1.43 (just for Cepheids). This comes from the period-luminosity relationship and some guy saying that this the relationship between them.

There is also this formula relating luminosity and abs magnitude:

L = 3.362 x 10^((140-2M)/5).

Are these the sort of things you are looking for??

Re: Astronomy

Posted: March 20th, 2009, 1:07 pm
by EastStroudsburg13
OK, that sounds like it would have helped. I don't remember the exact questions though, and our region doesn't make the tests public (I don't think).

Help!

Posted: March 23rd, 2009, 3:36 pm
by meg312
Hi guys,
It's obvious y'all know what you're talking about. I, however, do not know a thing about astronomy except for how to find the Big Dipper and Orion. Somehow, I was signed up for Astronomy. Now, with two weeks before the competition, I am realizing I need some major help! Any tips?

Re: Astronomy

Posted: March 23rd, 2009, 4:53 pm
by herewegoagain365
It's probably a good idea to check out the scioly.org Astronomy wiki (look under "Board Index"). It's also a good idea to look up and take notes on each of the topics on the rules sheet (since you're allowed to take either a binder or laptop, put your notes on there). Good luck!

Re: Astronomy

Posted: March 23rd, 2009, 4:54 pm
by herewegoagain365
Here's the link for the wiki:
http://scioly.org/wiki/Astronomy

Re: Astronomy

Posted: March 25th, 2009, 12:22 pm
by kyeras
I have the event this Saturday and my teacher never gave me the sheet for Astronomy but I'm supposed to get the stars and all their information, can any of you help me out and post what those stars are going to be? Thanks, Ky :D

Re: Astronomy

Posted: March 25th, 2009, 5:48 pm
by Sheogorath
Epsilon Aurigae and Betelgeuse are two

Re: Astronomy

Posted: March 26th, 2009, 5:56 am
by Flavorflav
What did you think of the NYS Astronomy event? Was it what you expected?

Re: Astronomy

Posted: March 26th, 2009, 5:17 pm
by herewegoagain365
kyeras wrote:I have the event this Saturday and my teacher never gave me the sheet for Astronomy but I'm supposed to get the stars and all their information, can any of you help me out and post what those stars are going to be? Thanks, Ky :D
DSOs: Circinus X-1, RU Virginis, Epsilon Aurigae, RX Andromedae, Z Andromedae, SN 1006, RX J0322-4300, G292.0+1.8, NGC 2440, Betelgeuse, RS Ophiuchi, Mira, T Tauri, RS Puppis, Hinds Variable Nebula.

Hope that's what you're looking for! Good luck.

Re: Astronomy

Posted: March 26th, 2009, 6:20 pm
by Sheogorath
Flavorflav wrote:What did you think of the NYS Astronomy event? Was it what you expected?
It was, it hasn't changed much in the past three years, I've done it since then, I just didn't get all the points for the times in the beginning section due to time constraints.