Ideas for university astronomy course.

[ed9428]

Hi all.

Thought I would tap into the vast source of ice in space member knowledge if I could.

I am a first year physics student at Newcastle University (NSW). I am currently doing an intro to astronomy course and have been given an assignment. I am in no way looking for answers, data or anything like that, just some ideas of where to start. The assignment is written below in bold.

Pick an interesting object in space and write a short essay (4 pages ~1200 words) outlining what is currently known about it. Where possible describe how observations of the object help explain or test the fundamental laws of physics. Also give a description of how you would go about making observations of this object using the Physics Department equipment. The feasibility of making these observations should be paramount. If necessary the observations could be part of a longer time scale such as a year. ALL references should be properly cited.

(Extra merit will be given for observations in which actual measurements can be made and Physical Laws tested.)


The equipment we have available is –
Meade™ LX200R (200 mm) telescope with GOTO control and tracking
Coronado™ Solarmax40 (40 mm) H-alpha Solar Telescope
8mm, 26mm and 32mm Plössl eyepieces
Various coloured filters.
Astronomix™ O-III and H-beta deep-sky filter
JMB™ neutral density filter (200mm) for looking at the Sun
A Meade™ Lunar Planetary Imager (CCD camera and image stacking software)
A Meade™ Deep Sky Imager (high light sensitivity CCD camera)

Canon™ EOS600D digital SLR camera (and hardware to attach to telescope)

Again, I am not after data just ideas. I am looking forward to doing the research myself.
Any help would be greatly appreciated.

Cheers, Kris.

[tlgerdes]

Hi Kris,

First, I would start with looking at some of the images in the deep space section. These can give some interesting persectives on our universe and what is out there. Then you can think of, how do some of these things come into existing and what/how do we explain them?

IE What is a planterary nebula and how do they form? What is a Herbig Harrow object? What is Bok Globule? What is the "dust" that appears in so many images? What is happening in Eta Carinae?

[AstralTraveller]

I think the next step is to look at what sort of data you can collect with this equipment. For example you can image and do photometry but not spectroscopy. For photometry you are limited to 'bright' (relatively) objects, 'long' exposures (I'm thinking several seconds or longer) and I suspect that very fine resolution (eg <0.01mag) is not possible. I'm assuming the equipment is fixed, which also removes some possibilities.

Some possibilities off the top of my head (alas none of which test physical laws):

- Variable star photometry. There are lots of interesting, poorly understood classes of variable. You need one where the period is not too long (you only have a year) not too short (the data should be able to be obtained by nightly to weekly observing) and not well understood (I don't think there is much point in observing cepheids).

- Asteroid photometry. To assess spin rates (and/or albedo variations).

- Asteroid occultations. To determine the size of asteroids. You would need some relatively cheap extra equipment. You would also need to be mobile.

- Supernova search. Probably not appropriate in that you don't actually produce data, others do that once the supernova is discovered. Also, Stu Parker will doubtless beat you to any new supernova (BTW he's having a lean spell now, it's been over a week since the last discovery).

BTW, that isn't a particularly impressive set of equipment. There must be hundreds of people on this forum with better.

[Dave2042]

Sounds like a fun assignment. As a physics graduate, I feel obliged to make some suggestions:


You could look at planets for gravitation and theories of planetary formation. Mercury is particularly interesting, as its orbit doesn't quite agree with Newtonian gravity and provides empirical support for general relativity (google "advance of perihelion").
Galaxies have all kinds of physics going on - gravity holding them together, dark matter explaining rotation curves, redshifts giving us the Hubble law, black holes in the center of some;
Nebulae could involve a discussion of emission and absorption spectra, including classical electrodynamics in dispersive media;
The sun - plasma physics, gravity, electromagnetism, nuclear physics.

[kustard]

As David (AstralTraveller) mentioned, variable stars are a great avenue for study. Picking a variable star with a relatively short period (say a week or so) is one way to introduce you to star magnification determinations and they can be studied both via imaging or visible observation. Lots of physics involved in regards to orbital rates and inclinations.

Peter Williams of the Sutherland Astronomical Society is a wealth of information about observing variables if you decide to go this route.

Cheers,
Simon

[Terry B]

I agree with the others that measuring a variable star would be a good start. Because you don't have photometry filters this makes it difficult to measure actual magnitudes. A good choice would be an eclipsing variable as relative magnitudes are fine. There are plenty of bright enough ones that multiple time series of a few hours worth of 10sec exposures with the SLR would give a satisfactory light curve. From this data using Keplers 3rd law lots of parameters of the target stars can be measured.

Cheers
Terry

[ed9428]

I knew you could all help me.
I spoke with my lecturer today and he mentioned the department might be getting a spectrograph which opens up the options a bit more.
Although i think i already have some good ideas now.
Will have to look into these ideas.
Thanks heaps.
Always open to more ideas too.
Will post when i have made a decision.

[OICURMT]

If you are looking to collect data at a reasonably fast rate and test it against the basic laws of physics, then I'd suggest that you study the libration of the moon.

With the equipment you have, you can easily collect photos of the moon throughout its phase cycle and compared the relative nodding of the moon back and forth. Using basic software, you can then measure the relative spatial displacement of a fixed point relative to the viewable face, analyzing the data and then formulate en equation to predict the amount of libration at any given time.

Designing and executing this experiment would satisfy all the requirements listed... and I believe that you could collect data over three months and have a reasonably amount to create a predictive model.

OIC!