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Re: Astronomy C

Posted: November 23rd, 2017, 11:02 am
by syo_astro
PM2017 wrote:...So should I be looking through all the jargon found in academic papers?...
...All...torturous...*looks at to do list of re-reading the ~50-60 citations used for my publication*...Look on the bright side?

More seriously, you shouldn't need or want everything from papers. It took me some years to get better at paper reading, it's a good skill imo (science reading). For a "general" (interested) audience, the important things are in the abstract, figures, introduction, and discussion / conclusions (an order like that or a similar one as papers can be sectioned differently). I remember reading ~1-3 abstracts per DSO and copying the figures. The analysis is typically just too hard to perform in 50 minutes...job security for me!

All that said, unless you think you have a tougher competition coming, it's probably better to focus on the *basics*, which people think they know but usually haven't mastered ;) (though, some papers / figures can be pretty fun to read regardless).

Happy thanksgiving!

Re: Astronomy C

Posted: November 25th, 2017, 10:59 am
by Supreme
Hey guys,

What programs do you guys recommend for the various calculations on the test? It would be of great help.

Thanks,
Supreme

Re: Astronomy C

Posted: November 25th, 2017, 11:01 am
by PM2017
Supreme wrote:Hey guys,

What programs do you guys recommend for the various calculations on the test? It would be of great help.

Thanks,
Supreme
What do you mean by programs?

Re: Astronomy C

Posted: November 25th, 2017, 11:19 am
by Adi1008
PM2017 wrote:
Supreme wrote:Hey guys,

What programs do you guys recommend for the various calculations on the test? It would be of great help.

Thanks,
Supreme
What do you mean by programs?
All you need to solve the math problems in Astronomy is a calculator

Re: Astronomy C

Posted: December 9th, 2017, 1:21 pm
by Ten086
Hi, I'm brand new to this event this year and am already very confused.

A few questions about DSOs:
Are questions about the discoveries of DSOs common? I'm struggling to find information about that for most of them, and was wondering if it's particularly important to know.
Also, would there be questions about the sources of images, like "from what telescope did this image data come from" or "how big of an area does this image cover" or is it pretty much just "what DSO is this image of?"
This is probably really really dumb, but do SN W49B and SN 1987A refer to the remnants of the supernovas (supernovae?) or the supernovas themselves? I assumed it had to be the remnants because they're objects, but the wikipedia page for SN 1987A refers to the actual supernova so I got confused. If it is the remnants, why do they use SN instead of SNR?

And a few questions about stellar evolution:
What is the relationship between HII regions and emission nebulae? I've found sites that have said a lot of different things including: the parts of HII regions that glow are called emission nebulae, they're the same thing, an HII region is a type of emission nebula, and HII regions exist in emission nebula areas... which, if any, is right? D:
Same thing with giant molecular clouds, stellar nurseries, and nebulae...are they the same things? Are they types of each other?? Are they related in any way??? I'm just really lost ;__;

Also, is there an accepted Hubble Constant or are scientists still yelling at each other over it? If there's a question that requires using it, would you just use something around 70?

Sorry for being so dumb :'(

Re: Astronomy C

Posted: December 9th, 2017, 4:10 pm
by Unome
Ten086 wrote:Also, is there an accepted Hubble Constant or are scientists still yelling at each other over it? If there's a question that requires using it, would you just use something around 70?
The second one, and yes. I'll get to the rest later (or more likely, someone else will).

Re: Astronomy C

Posted: December 9th, 2017, 5:44 pm
by Adi1008
Unome wrote:
Ten086 wrote:Also, is there an accepted Hubble Constant or are scientists still yelling at each other over it? If there's a question that requires using it, would you just use something around 70?
The second one, and yes. I'll get to the rest later (or more likely, someone else will).
The short answer is that there's still a ton of debate over what the Hubble Constant is. Some surveys say about 67, other say about 72, depending on the method. Usually on a Science Olympiad test, they'll tell you what value to assume or they'll accept a wide range of answers knowing how much accepted values for Hubble's Constant can vary. Generally speaking, using 70 km/s/Mpc is safe.

A commentary by Wendy L. Freedman discusses this in more detail and includes this figure:
Image
Article on this wrote:Until about 2010, it looked like the CMB and galaxy estimates of H0 were both going to converge to the same answer. But as both types of experiment became more precise, their uncertainty bands overlapped less and less.

Re: Astronomy C

Posted: December 12th, 2017, 9:12 am
by Unome
Ten086 wrote:Are questions about the discoveries of DSOs common? I'm struggling to find information about that for most of them, and was wondering if it's particularly important to know.
The appear, but I wouldn't really consider them common. Most aren't that hard to find though, between Wikipedia and news articles you can usually get a date or year and a specific observatory or such.
Ten086 wrote:Also, would there be questions about the sources of images, like "from what telescope did this image data come from" or "how big of an area does this image cover" or is it pretty much just "what DSO is this image of?"
Those are definitely viable questions, in addition to question about the spectral bands and general portions of the electromagnetic spectrum used in an image.
Ten086 wrote:This is probably really really dumb, but do SN W49B and SN 1987A refer to the remnants of the supernovas (supernovae?) or the supernovas themselves? I assumed it had to be the remnants because they're objects, but the wikipedia page for SN 1987A refers to the actual supernova so I got confused. If it is the remnants, why do they use SN instead of SNR?
SN 1987A is the supernova, while SN W49B is the remnant. nomenclature is not necessarily helpful in Astronomy.
Ten086 wrote:And a few questions about stellar evolution:
What is the relationship between HII regions and emission nebulae? I've found sites that have said a lot of different things including: the parts of HII regions that glow are called emission nebulae, they're the same thing, an HII region is a type of emission nebula, and HII regions exist in emission nebula areas... which, if any, is right? D:
Same thing with giant molecular clouds, stellar nurseries, and nebulae...are they the same things? Are they types of each other?? Are they related in any way???
A molecular cloud is a cloud of gas consisting almost exclusively of molecular hydrogen. When a section collapses and forms a star, the star formation (specifically, the ignition of fusion) creates a shock wave that propagates some distance through the cloud, ionizing it and turning it into an H II region (atomic H+).

An emission nebula is any ionized cloud of gas - this includes the H II regions formed from star birth (the most common type of emission nebula) as well as those deriving energy from other sources. For example, a planetary nebula is ionized by the collapse of the star, but it is not an H II region because it doesn't involve stellar birth (according to the traditional narrow definition).

A stellar nursery is an ill-defined term for an area with many stars being formed. A nebula is just a general purpose term for a cloud of dust.

Re: Astronomy C

Posted: December 12th, 2017, 10:11 am
by Magikarpmaster629
Unome wrote:
Ten086 wrote:Also, would there be questions about the sources of images, like "from what telescope did this image data come from" or "how big of an area does this image cover" or is it pretty much just "what DSO is this image of?"
Those are definitely viable questions, in addition to question about the spectral bands and general portions of the electromagnetic spectrum used in an image.
I'd disagree that questions asking which specific telescope and angular size of images show up frequently (actually, angular size could show up if it can be inferred from the image), but yeah, questions asking for EM range appear all the time. I'd also agree with everything else in your post.

Re: Astronomy C

Posted: December 12th, 2017, 11:10 am
by Unome
Magikarpmaster629 wrote:
Unome wrote:
Ten086 wrote:Also, would there be questions about the sources of images, like "from what telescope did this image data come from" or "how big of an area does this image cover" or is it pretty much just "what DSO is this image of?"
Those are definitely viable questions, in addition to question about the spectral bands and general portions of the electromagnetic spectrum used in an image.
I'd disagree that questions asking which specific telescope and angular size of images show up frequently (actually, angular size could show up if it can be inferred from the image), but yeah, questions asking for EM range appear all the time. I'd also agree with everything else in your post.
Didn't notice angular size (agreed that that's uncommon except where it can be inferred from the image) but I've seen plenty of questions asking about the telescope that took the image.