Astronomy C

[pihi]

Hmmm I have a question.

Say you know a galaxy has a hydrogen line at 656 nm. The redshifted line is now at 1115 nm. What would be the redshift value and how fast would the galaxy be going. Also, how far is the galaxy away from us? (H= 70)

Check my work please

So you can find redshift by using (observed - emitted)/emitted = (1115-656)/656 = 459/656 = .7 This is the redshift value.
Now you can use v= zc = .7 * 300000 km/s = 210000 km/s. This is how fast the galaxy is moving away from us.
Then you can use Hubble's Law for distance. D = V/H = (210000 km/s)/(70 km/s/Mpc) = about 3000 Mpc.

Did I do it right? Any response would be helpful

[CurryGuy123]

I feel like this may have been asked before, but do you guys use laptops or binders? And whichever you use, do you have your partner have the same stuff in each or do you each keep different stuff and split the test?

Thanks!

[Infinity Flat]

I feel like this may have been asked before, but do you guys use laptops or binders? And whichever you use, do you have your partner have the same stuff in each or do you each keep different stuff and split the test?

Thanks!

We do two laptops, with the same info on each. Typically we'll split the test, and then go over it together at the end.

[EastStroudsburg13]

We only had one binder at regionals, but we'll get either another binder or a laptop for states.

[syo_astro]

From invitationals to states we used one binder and one laptop. The binder we put in really quick info on DSOs, formulas, diagrams. The laptop we had a lot of extra information. It worked out pretty well for us, but it really just depends what is easiest to sort through (for me it was the binder, my partner wanted the laptop).

[Gillen]

Hmmm I have a question.

Say you know a galaxy has a hydrogen line at 656 nm. The redshifted line is now at 1115 nm. What would be the redshift value and how fast would the galaxy be going. Also, how far is the galaxy away from us? (H= 70)

Check my work please

So you can find redshift by using (observed - emitted)/emitted = (1115-656)/656 = 459/656 = .7 This is the redshift value.
Now you can use v= zc = .7 * 300000 km/s = 210000 km/s. This is how fast the galaxy is moving away from us.
Then you can use Hubble's Law for distance. D = V/H = (210000 km/s)/(70 km/s/Mpc) = about 3000 Mpc.

Did I do it right? Any response would be helpful

Yeah, that looks good to me.

[pihi]

Hmmm I have a question.

Say you know a galaxy has a hydrogen line at 656 nm. The redshifted line is now at 1115 nm. What would be the redshift value and how fast would the galaxy be going. Also, how far is the galaxy away from us? (H= 70)

Check my work please

So you can find redshift by using (observed - emitted)/emitted = (1115-656)/656 = 459/656 = .7 This is the redshift value.
Now you can use v= zc = .7 * 300000 km/s = 210000 km/s. This is how fast the galaxy is moving away from us.
Then you can use Hubble's Law for distance. D = V/H = (210000 km/s)/(70 km/s/Mpc) = about 3000 Mpc.

Did I do it right? Any response would be helpful

Yeah, that looks good to me.

Ok Thank you!

[TheWrightBrother]

i did reach for the stars this year and am thinking about astronomy next year in high school. any tips?

[Cheesy Pie]

Apply what you already know from RFTS to Astronomy, and do some extra research.

[EastStroudsburg13]

Hahahaha, you wish it was that simple.

RFTS and Astro are similar in some ways, but VERY different in others. Astro basically has three main sections: DSO's, calculations, and conceptual stuff.

The DSO's are kind of like in Reach, but you don't need to identify them, and they're normally sort of obscure. You need to know the defining characteristics of them, and how they relate to the overall topic of that year. The [wiki]Astronomy/DSOs[/wiki] has a table with past DSO's.

The conceptual stuff varies from year to year. It is usually a broad astronomical topic, and the test questions can go very in depth. Basically, you have to know it inside and out.

The calculations are completely new from B to C. Some of them have to deal with distance, others luminosity, temperature, redshift, etc. You have to be able to use them in a given problem. There's a formula sheet on the Astronomy Wiki.

That's the gist of it. True, you have the background of RFTS, but this is like that on steroids. The good thing is, EACH partner is allowed a binder or laptop (without Internet access). It's pretty fun when you start studying it, and it's my favorite event by far, which is saying something considering how much I like Remote Sensing.