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Epicfail21 wrote:

pjgscioisamazing wrote:

Epicfail21 wrote:Does anyone know have any scores for the R.C. Murphy/P. J. Gelinas Scrimmage?
I'm just little curious to see how everyone else did on that test.

All I can remember is that the top two scores were tied with 95. I don't remember the rest.

Thank you very much!

Schrodingerscat wrote:

ilovecatsyl wrote:Alright thanks!

Back to that right ascension and declination thing:
So is the right ascension the amount of time from which the star/constellation rises and sets? If so how does tie in with longitude and a star chart?
Declination makes a little more sense. I'm pretty sure it's the latitude in which the star/constellation appears in?

The actual calculations of an objects position based upon these coordinates involves a fair amount of trigonometry which you would likely not be expected to know for this event. However, the the right ascension is the local sidereal time when the star reaches its peak altitude. This is a clock that runs a few minutes shorter than 24 hours to have a 364 day year accounting for the suns relative motion through the celestial sphere, which the normal clock is designed to keep at the same time. This time is also unique the observers longitude to perfectly account for it, as opposed to the rougher system of time zones. Declination can be used a little more easily with the observer's latitude. It tells you that the North Celestial Pole (or south if in the southern hemisphere) is at an angle to the horizon equal to your latitude. The celestial equator will be be at that angle to the zenith, and the complement of that angle to the horizon. The complement of your latitude will also tell you whether a star is circumpolar. (Eg at 40 degrees N, and star between 50 and 90 degrees declination will be circumpolar.) Finally, the negative complement of your latitude will tell you how far or south (oppose of your hemisphere) you can see in the celestial sphere. (So at 40 degrees I can see stars from -50 to 90 declination). This could also be used to see a star, as if I wanted to see a star at -80 declination, I know I would need to travel below 10 degrees North to be able to see it at all. Also for why it would be useful with a star chart: general purpose sky maps will often use this system for a grid, so you might be able to use the coordinates to find it quicker. (Or maybe a chart they give your in competition would have some coordinates that would help you identify).

ilovecatsyl wrote:

Schrodingerscat wrote:

ilovecatsyl wrote:Alright thanks!

Back to that right ascension and declination thing:
So is the right ascension the amount of time from which the star/constellation rises and sets? If so how does tie in with longitude and a star chart?
Declination makes a little more sense. I'm pretty sure it's the latitude in which the star/constellation appears in?

The actual calculations of an objects position based upon these coordinates involves a fair amount of trigonometry which you would likely not be expected to know for this event. However, the the right ascension is the local sidereal time when the star reaches its peak altitude. This is a clock that runs a few minutes shorter than 24 hours to have a 364 day year accounting for the suns relative motion through the celestial sphere, which the normal clock is designed to keep at the same time. This time is also unique the observers longitude to perfectly account for it, as opposed to the rougher system of time zones. Declination can be used a little more easily with the observer's latitude. It tells you that the North Celestial Pole (or south if in the southern hemisphere) is at an angle to the horizon equal to your latitude. The celestial equator will be be at that angle to the zenith, and the complement of that angle to the horizon. The complement of your latitude will also tell you whether a star is circumpolar. (Eg at 40 degrees N, and star between 50 and 90 degrees declination will be circumpolar.) Finally, the negative complement of your latitude will tell you how far or south (oppose of your hemisphere) you can see in the celestial sphere. (So at 40 degrees I can see stars from -50 to 90 declination). This could also be used to see a star, as if I wanted to see a star at -80 declination, I know I would need to travel below 10 degrees North to be able to see it at all. Also for why it would be useful with a star chart: general purpose sky maps will often use this system for a grid, so you might be able to use the coordinates to find it quicker. (Or maybe a chart they give your in competition would have some coordinates that would help you identify).

I'm sorry...you're confusing me even more. This is my first time with science olympiad and going deep within astronomy.

At first you explained that "the right ascension is the local sidereal time when the star reaches it's peak altitude" which I infer is the time it takes for the star to go from horizon to peak altitude...then you mentioned a clock and related it to ours which made me think that right ascension is time that the star takes to orbit our horizon (according to our eyes).

Then the only thing I picked up from declination what that it helped you find the perfect spot to see a star...

foreverphysics wrote:So how likely are the chances going to be that they're going to have a planetarium at Nats? Because my partner and I have had about zero experience with actual looking-and-finding. The only constellation I can ever find is Orion, and sometimes Ursa Minor.

foreverphysics wrote:So how likely are the chances going to be that they're going to have a planetarium at Nats? Because my partner and I have had about zero experience with actual looking-and-finding. The only constellation I can ever find is Orion, and sometimes Ursa Minor.

triplej wrote:hey guys...just wondering what's a good way to learn how to identify stars with a star chart because I got put on this event in regionals and messed up badly not knowing a lot of it was constellations and not single star identification. And I've looked at the practice tests and can do most all the other stuff but I have no idea how to learn or do this.