Author Topic: Alice's MSc Astrophysics reports  (Read 37328 times)

Alice

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Re: Alice's MSc Astrophysics reports
« Reply #180 on: January 09, 2013, 10:37:25 am »
Will you actually go outside at night and look up?

My degree is in plant biochemistry, which is of no use when someone asks "What is wrong with my African violet?"

Sadly not. Seems that apart from the dissertation if we're lucky, we won't be working with any real data at all, either. Which, as you can imagine, bothers me a great deal - I think I ranted about this earlier so won't repeat it.

Ioanna, the girl on the course with a camera, sends this picture - she apologises for it being bad quality, bless her. It wasn't her fault; it's not the brightest of rooms. The speech bubble says "I can serve you, but not your friend - he's a BARRED SPIRAL!"

Alice

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Re: Alice's MSc Astrophysics reports
« Reply #181 on: January 10, 2013, 04:18:48 pm »
Eeeeep - galactic maths coming up soon! :o

Todd Howard

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Re: Alice's MSc Astrophysics reports
« Reply #182 on: February 06, 2013, 08:29:55 am »
Eeeeep - galactic maths coming up soon! :o
Eeeeep indeed.. :o Gets really scary by page 18.. Hope it goes ok for ya

Alice

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Re: Alice's MSc Astrophysics reports
« Reply #183 on: February 06, 2013, 07:16:36 pm »
Last week it was five dimensional hypersurfaces of ring doughnuts (that is what I understood of it). This week it was the Jeans Equations and how to derive them. I am in a perpetual state of bewilderment :D

Next topic is the Interstellar Medium, though, and the first thing we look at will be the 21cm line, so I am very excited about that! ;D

Alice

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Re: Alice's MSc Astrophysics reports
« Reply #184 on: February 13, 2013, 09:28:00 am »
We've started on the interstellar medium . . . And have been going through notations (such as OIII instead of O2+) and how spectra form and everything that I learned here in the zoo, especially whilst writing up the Peas project. 8)

I also finally found out exactly what forbidden lines are*. They are spectral lines made from transitions of electrons that do not happen on Earth. They don't happen here because we can't get a good enough vaccuum to prevent frequent collisions between atoms. Now, when a forbidden line is produced, it's a transition that is rather unlikely to happen and not at an energy level the atom particularly "likes", and this state will be immediately destroyed by a collision - if a collision happens. In space, there's plenty of time for the line to be produced. In professional notation, square brackets around the name indicate a forbidden line, [OII] for example. ;D ;D

* Yes, I could have looked it up and it's probably on this forum, but it was one of the 100,000,000,000 things I simply didn't. ::)

StephanieC

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Re: Alice's MSc Astrophysics reports
« Reply #185 on: February 16, 2013, 03:40:05 pm »
It actually was in this forum that I learned [OIII] was "forbidden". My immediate reaction was, "Seriously guys? The stuff's all over the place!" It took me a while to find something to tell me why (and by extension, where) it was considered "forbidden".

Edd

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Re: Alice's MSc Astrophysics reports
« Reply #186 on: February 18, 2013, 01:48:52 pm »
Today, in Stellar Structure and Evolution, we finished with the completely incomprehensible maths to do with equilibrium etc (I still don't understand what "polytropes" actually ARE) and got onto nuclear synthesis - in other words, how stars make chemical elements.
I should read this thread more often. Anyway, I remember polytropes being poorly explained when I first encountered them. I think it pretty much boils down to just being the case where pressure is proportional to density^[(n+1)/n] for some n.

It's one of those things that every textbook seems to assume you know, and noone knows why it assumes you know.

Dex is the other one I remember from around the same time - noone explained what this unit was. It's actually just a logarithmic measure, so 1 dex is a factor of 10, 2 dex is 100 etc. But noone told me that and expected me to just know what 0.3 dex meant and it wasn't in any of the textbooks...
When I look up at the night sky and think about the billions of stars out there, I think to myself: I'm amazing. - Peter Serafinowicz

Alice

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Re: Alice's MSc Astrophysics reports
« Reply #187 on: February 20, 2013, 03:14:00 pm »
I've never come across dex, fortunately . . .

So, I gather there are distinct polytropes of stars? Do they tend to be around the same, according to mass or whatever? Or is it different for each star? And how on earth can you tell, anyway, observationally? The trouble with that unit was that not a single observational result came into it. It was all theory, without a shred of indication whether any of it had ever been observed or proven!

Alice

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Re: Alice's MSc Astrophysics reports
« Reply #188 on: March 04, 2013, 02:58:24 am »
I actually got round to writing an OOTD based on one of my lectures :D I had to interrupt it towards the end to butt in about SDSS and quasars, obviously . . . Fortunately Jim the professor didn't mind ;D

JohnF

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Re: Alice's MSc Astrophysics reports
« Reply #189 on: March 14, 2013, 08:17:38 pm »
Alice, I think you said something about Enceladus somewhere?

Video link to a lecture - http://royalsociety.org/events/2013/dynamic-atmosphere-enceladus/
John C. Fairweather - http://www.jcfwebsite.co.uk

JohnF

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Re: Alice's MSc Astrophysics reports
« Reply #190 on: June 11, 2013, 12:19:19 pm »
Any end of year report?
John C. Fairweather - http://www.jcfwebsite.co.uk

Budgieye

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Re: Alice's MSc Astrophysics reports
« Reply #191 on: June 14, 2013, 08:34:30 pm »
Let us hear your summary!