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Re: Astronomy C

Posted: October 2nd, 2016, 1:50 pm
by Magikarpmaster629
Alright
a) Ultraviolet, Galaxy Evolution Explorer
b) Omicron Ceti A
c) Mass loss
d) Not entirely sure, but I'd guess that this phenomenon is rather faint and can only be viewed in UV. The combination of these two things would require high tech observatories that have only been available in recent years

Re: Astronomy C

Posted: October 5th, 2016, 6:44 am
by Adi1008
Magikarpmaster629 wrote:Alright
a) Ultraviolet, Galaxy Evolution Explorer
b) Omicron Ceti A
c) Mass loss
d) Not entirely sure, but I'd guess that this phenomenon is rather faint and can only be viewed in UV. The combination of these two things would require high tech observatories that have only been available in recent years
Correct; your turn!

Re: Astronomy C

Posted: October 5th, 2016, 7:26 pm
by Magikarpmaster629
It is often said that type Ia supernovae are reliable standard candles for intergalactic distance calculations. What is meant by the term 'standard candle' and why is the previous statement not entirely true of type Ia supernovae?

After answering that, part two of the question: There is a linear relationship between the absolute magnitude and an observable quantity of type Ia supernovae. What is the name of the relationship, and what quantity does the relationship use?

Re: Astronomy C

Posted: October 5th, 2016, 8:18 pm
by bhavjain
Magikarpmaster629 wrote:It is often said that type Ia supernovae are reliable standard candles for intergalactic distance calculations. What is meant by the term 'standard candle' and why is the previous statement not entirely true of type Ia supernovae?

After answering that, part two of the question: There is a linear relationship between the absolute magnitude and an observable quantity of type Ia supernovae. What is the name of the relationship, and what quantity does the relationship use?
1. 'Standard candle' refers to a group of objects that has a known luminosity. Can calculate distance by comparing absolute magnitude with apparent magnitude, if you have a standard candle, via the distance modulus. In double degeneraye progenitors, the combined mass may exceed the Chandrasekhar limit, and so the absolute magnitude commonly referred to as -19.3 may not be true for all type 1a supernova. Also some type Ia supernovas are intrinsically more luminous than others, and each one has a different mass, spin, combustion, ignition, etc. Thus they are truly 'standardizable' candles.

2. Phillips Relationship; the quantity is decline-rate, or the rate at which brightness declines.

Re: Astronomy C

Posted: October 5th, 2016, 8:43 pm
by Magikarpmaster629
bhavjain wrote:
Magikarpmaster629 wrote:It is often said that type Ia supernovae are reliable standard candles for intergalactic distance calculations. What is meant by the term 'standard candle' and why is the previous statement not entirely true of type Ia supernovae?

After answering that, part two of the question: There is a linear relationship between the absolute magnitude and an observable quantity of type Ia supernovae. What is the name of the relationship, and what quantity does the relationship use?
1. 'Standard candle' refers to a group of objects that has a known luminosity. Can calculate distance by comparing absolute magnitude with apparent magnitude, if you have a standard candle, via the distance modulus. In double degeneraye progenitors, the combined mass may exceed the Chandrasekhar limit, and so the absolute magnitude commonly referred to as -19.3 may not be true for all type 1a supernova. Also some type Ia supernovas are intrinsically more luminous than others, and each one has a different mass, spin, combustion, ignition, etc. Thus they are truly 'standardizable' candles.

2. Phillips Relationship; the quantity is decline-rate, or the rate at which brightness declines.
Yeah, that works.

Re: Astronomy C

Posted: October 5th, 2016, 8:59 pm
by bhavjain
What is the hottest white dwarf discovered thus far? Which galaxy is it in? What is its record-setting temperature?

Re: Astronomy C

Posted: October 5th, 2016, 9:12 pm
by Adi1008
bhavjain wrote:What is the hottest white dwarf discovered thus far? Which galaxy is it in? What is its record-setting temperature?
1. RX J0439.8-6809
2. Milky Way
3. about 250,000K

Re: Astronomy C

Posted: October 5th, 2016, 10:24 pm
by bhavjain
Adi1008 wrote:
bhavjain wrote:What is the hottest white dwarf discovered thus far? Which galaxy is it in? What is its record-setting temperature?
1. RX J0439.8-6809
2. Milky Way
3. about 250,000K
Yep. (Did you have it memorized :P) Your turn.

Re: Astronomy C

Posted: October 6th, 2016, 6:31 pm
by Adi1008
bhavjain wrote:
Adi1008 wrote:
bhavjain wrote:What is the hottest white dwarf discovered thus far? Which galaxy is it in? What is its record-setting temperature?
1. RX J0439.8-6809
2. Milky Way
3. about 250,000K
Yep. (Did you have it memorized :P) Your turn.
LOL I wish my memory was that good; I just found it on my notes xD

Here's my question:

Image

(a) What do the colored lines represent?
(b) Rank A, B, C, and D in terms of mass
(c) What is the x-coordinate of the point labeled 2015, in Kelvin?

Re: Astronomy C

Posted: October 9th, 2016, 11:01 am
by Magikarpmaster629
Ehh, here goes
A. Different evolutionary tracks?
B. A, D, C, B
C. ~50,118 K