Astronomy C

Test your knowledge of various Science Olympiad events.
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jonboyage
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Re: Astronomy C

Post by jonboyage »

An easier question so hopefully some others join in:

Two stars are in transiting orbit around each other. One star has twice the radius and half the temperature of the other. When both stars are completely visible, call that time A. When the smaller star is completely in front of the larger star, call that time B. When the smaller star is completely behind the larger star, call that time C. Rank the observed brightness of the system at times A, B and C.
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Re: Astronomy C

Post by PM2017 »

jonboyage wrote:An easier question so hopefully some others join in:

Two stars are in transiting orbit around each other. One star has twice the radius and half the temperature of the other. When both stars are completely visible, call that time A. When the smaller star is completely in front of the larger star, call that time B. When the smaller star is completely behind the larger star, call that time C. Rank the observed brightness of the system at times A, B and C.
Increasing or decreasing? (I know the answer, but I won't say, so others can join, like you said.)
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Re: Astronomy C

Post by jonboyage »

PM2017 wrote:
jonboyage wrote:An easier question so hopefully some others join in:

Two stars are in transiting orbit around each other. One star has twice the radius and half the temperature of the other. When both stars are completely visible, call that time A. When the smaller star is completely in front of the larger star, call that time B. When the smaller star is completely behind the larger star, call that time C. Rank the observed brightness of the system at times A, B and C.
Increasing or decreasing? (I know the answer, but I won't say, so others can join, like you said.)
I’m sorry I didn’t see this until now, I guess you replied so quickly I might still have been on the page so I didn’t get a notification.

Let’s go for increasing: dimmest, middle, brightest
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Re: Astronomy C

Post by sciolyPA »

jonboyage wrote:
PM2017 wrote:
jonboyage wrote:An easier question so hopefully some others join in:

Two stars are in transiting orbit around each other. One star has twice the radius and half the temperature of the other. When both stars are completely visible, call that time A. When the smaller star is completely in front of the larger star, call that time B. When the smaller star is completely behind the larger star, call that time C. Rank the observed brightness of the system at times A, B and C.
Increasing or decreasing? (I know the answer, but I won't say, so others can join, like you said.)
I’m sorry I didn’t see this until now, I guess you replied so quickly I might still have been on the page so I didn’t get a notification.

Let’s go for increasing: dimmest, middle, brightest
First post ever on a forum, so sorry if I formatted it wrong.
Answer: C, B, A
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Re: Astronomy C

Post by jonboyage »

sciolyPA wrote:
jonboyage wrote:
PM2017 wrote: Increasing or decreasing? (I know the answer, but I won't say, so others can join, like you said.)
I’m sorry I didn’t see this until now, I guess you replied so quickly I might still have been on the page so I didn’t get a notification.

Let’s go for increasing: dimmest, middle, brightest
First post ever on a forum, so sorry if I formatted it wrong.
Answer: C, B, A
Correct!
Your turn.
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Re: Astronomy C

Post by sciolyPA »

A star has three times the mass of the sun, what would its schwarzschild radius be? (Also how do you hide your answer behind an answer box and how do you upload math equations to show work?)
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Re: Astronomy C

Post by Unome »

Code: Select all

[hide]visible text|hidden text[/hide]

Code: Select all

[math]LaTeX code[/math]
Schwarzschild radius = [math]\frac{2GM}{c^2}[/math]
The Sun's mass is approximately [math]1.9*10^30 kg[/math], [math]G = 6.67*10^{-11}[/math] in SI units, and [math]c = 3*10^8 m/s[/math].
Therefore [math]R = 8.45 km[/math]
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Re: Astronomy C

Post by sciolyPA »

Unome wrote:

Code: Select all

[hide]visible text|hidden text[/hide]

Code: Select all

[math]LaTeX code[/math]
Schwarzschild radius = [math]\frac{2GM}{c^2}[/math]
The Sun's mass is approximately [math]1.9*10^30 kg[/math], [math]G = 6.67*10^{-11}[/math] in SI units, and [math]c = 3*10^8 m/s[/math].
Therefore [math]R = 8.45 km[/math]

Looks good and thanks for the help!
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Re: Astronomy C

Post by Unome »

Image
1. What DSO was this data gathered from?
2. Is this image a spectrum, light curve, or radial velocity graph? (meta question to anyone who can answer - what would be a good way to phrase this without listing options?)
3. What orbital phenomenon does this image show?
4. How many times brighter is the star at peak brightness than at minimum?
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Re: Astronomy C

Post by PM2017 »

Unome wrote:Image
1. What DSO was this data gathered from?
2. Is this image a spectrum, light curve, or radial velocity graph? (meta question to anyone who can answer - what would be a good way to phrase this without listing options?)
3. What orbital phenomenon does this image show?
4. How many times brighter is the star at peak brightness than at minimum?
an answer to your meta question: You could ask, "What type of chart is shown in this image?"

(also, the sad feel when you can answer all the questions except for the first, and probably easiest one... I'm actually clueless as to which DSO this is...)
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