School Science Experiment! :D

Mr. Subatomic · #1 13-05-2007, 04:08 PM

Hey guys,

I'm in year 10 at High School this year and I have been assigned what the Science department calls an 'Open Ended Investigation'. It's basically where I undertake an experimental investigation that answers a specific question, document it down to every single minute detail and hand it in for assessment.

I bought a 10" Dobsonian telescope at the beginning of this year, so I figured "Hey, why don't I just do somethingwith that!", and that's where you guys come in!

So if you have any ideas on astronomy related experiments that I can use my telescope with to undertake, that would be great. Maybe you could suggest an astronomy myth I could expel through experimentation. Feel free to put forward a challenging idea, because I want an experiment that will be an exciting, challenging experiment that will provide strong, relevant data, and it's fine if there's mathematical equations involved.

Thanks a lot!

Chrissyo (Chris) · #2 13-05-2007, 05:25 PM

Howdy!

I was your age when I got my 10" dob. It's a pretty neat instrument

I'm not really sure of what you could do. The asteroid Vesta is currently brightening and will reach its opposition at around the end of the month. Perhaps you could go out every night (or as often as the weather allows) and compare its brightness to that of a nearby star of constant magnitude such as Antares. Then you could record an estimated value for each night then at the end of the month compare it to the actual values of Vesta's magnitude. That wouldn't be answering a question per say, but its investigative I suppose.

Kal (Andrew) · #3 13-05-2007, 05:45 PM

How about you do an experiment to see how the Jetstream affects viewing? You could use the Jetstream maps (found here) to see how strong the Jetstream is above your location on any given night, and then use your telescope to rate the seeing conditions - for example by using the pickering scale. After you have collected the data you can analyse it and see how the Jetstream directly affects observing conditions.

xelasnave · #4 13-05-2007, 05:50 PM

Using known stars magnitude (this is reliable addmissible data) you could make observations in various locations to plot sky polution.

You see them here but not there

.. Hypotisis..light polution.. some one else can explain steps better but your teacher would have guided you on the expectation.

That is not as easy as it sounds, if reasonable sample were to be taken.

Good luck

.

What a wonderful opportunity for you...
alex

freespace · #5 13-05-2007, 05:52 PM

I was going to suggest you can observe Jupiter's satellites and calculate their orbitals, but then I realised you have a dob, and they aren't too crash hot for fine measurements.

Though, if you can take pictures, then you can do it that way, and knowing the size of Jupiter's planetary disc, you can work out how much the moons are moving each night, which would give you some idea of how fast it is moving - just like the forefather's of astronomy!

Even if you fail to work it out accurately, it is /still/ a good project, in that you can document what you did wrong, etc. Science is more than about getting the right results, its also about learning what no to do.

As they say, you are an expert when you have made all possible mistakes at least once

Also, remember you have far superior optics and time keeping than the first people who calculated the periods of Jupiter's moons, not to mention a wealth of information and a great deal more computing power.

mickoking · #6 13-05-2007, 06:24 PM

I can't resist...

Blow something up...for science

xelasnave · #7 14-05-2007, 09:36 AM

Mick your idea seems to be the one..

No one can offer anything better it seems.

I suspect Myth Busters have had an influence upon you.

alex

mickoking · #8 14-05-2007, 07:09 PM

Quote:

Originally Posted by xelasnave

Mick your idea seems to be the one..

No one can offer anything better it seems.

I suspect Myth Busters have had an influence upon you.

alex

True

Mr. Subatomic · #9 14-05-2007, 07:12 PM

Thanks guys these are great ideas, you've really helped!

And yes, I've been bitten by the Mythbusters bug as well, I mean, blowing stuff up is science, well thats at least thats what Jamie and Adam say!

freespace · #10 14-05-2007, 11:13 PM

Quote:

Originally Posted by Mr. Subatomic

Thanks guys these are great ideas, you've really helped!

And yes, I've been bitten by the Mythbusters bug as well, I mean, blowing stuff up is science, well thats at least thats what Jamie and Adam say!

Try to avoid the mythbuster bug of bad science though.

If in doubt, I would be happy to review your experimental procedure.

*is a physics student, loves experimental work, stickler for accuracy*

higginsdj · #11 15-05-2007, 12:52 PM

Well you could pick a bright visible southern variable star then calculate it's period and amplitude!

Cheers

freespace · #12 15-05-2007, 01:53 PM

Quote:

Originally Posted by higginsdj

Well you could pick a bright visible southern variable star then calculate it's period and amplitude!

Cheers

I was going to suggest that, but figured it might be too advanced for a y10 student.

FWIW, I am currently doing a research project on post-AGB plantary-nebula precursors - finding which ones are variable, and how their variability is modulated.

Some of the data is here: http://www.shuningbian.net/astro/ASA...B%20stars.html

The analysis: http://www.shuningbian.net/astro/analysis.html

Though if Mr. Subatomic would like to do it, I would be happy to help.

Cheers,
Steve

Mr. Subatomic · #13 15-05-2007, 05:16 PM

Thanks Steve. I think I'm leaning toward your idea of calculating the orbital velocities of Jupiter's four brightest, major moons: Io, Ganymede, Callisto and Europa.

Here's how I think I will do it, anyone feel free to correct me if Im wrong, or even improve on what I think:

I would take observations or photographs of Jupiter at the same time each night for a number of nights. When I observe that one of the satellites appears back in the position that I first observed, I'll know it has completed approximately one revolution. From the known orbital distances, I can then calculate the velocities of the moons

Around now is probably the best time to do an expreiment like this, because Jupiter is near opposition. Hopefully the weather will behave, light pollution won't hinder views (I live in the Balmain area of Sydney near the CBD, a lot of light pollution!) and hopefully the moon won't do so either, because the two bodies will be close on some night's. I think I'll go out a couple of nights before the experiment and see if Jupiter is affected or not.

If worse comes to worse on some nights, I always have the visual diagrams of Jupiter's satellites in AS&T, but does anyone know a site where I can get a simulated image of, for example, the positioning of Jupiter's moons at a certain date/time?

Thanks for all of your help.

Cheers.

bojan · #14 15-05-2007, 09:35 PM

For a program showing Jupiter moons have a look here:
http://www.astrosurf.com/rondi/programmes/index.htm
(Jupiter_2)

ballaratdragons (Ken) · #15 15-05-2007, 09:35 PM

You could always try something different. There was a few scientists experimenting with Mylar and water to make a telescope!

What they did was dug a hole in the ground (you could make a frame instead) covered it with Mylar, then placed a diagonal and focuser about 1 metre above it. Then they added water drop by drop until the mirror had the right curve in it to pull focus in the EP!!!!!

They didn't expect it to work very well but it did

Must be able to google something about it

ballaratdragons (Ken) · #16 15-05-2007, 09:51 PM

and here's another project using Mylar as a telescope for measuring infra-red.

http://home.freeuk.com/m.gavin/flux.htm

freespace · #17 15-05-2007, 10:34 PM

Once you know how long each moon takes to orbit Jupiter, you can work out a few things:

First, you can measure the orbits, since you know how big Jupiter's is, and how far away it is, etc. You can work out the semimajor axis of the orbits as a fraction of Jupiter's real size, then you just multiply by Jupiter's real size to find roughly the semimajor axis of the orbits.

Now using the generalised form is here: http://en.wikipedia.org/wiki/Kepler%...tion#Third_law, just use Jupiter's mass for M, and the semimajor axis of the orbits as a, and you should be able to work out what m is, as a fraction of M. So you would just really need to set M = 1, then m would be some very small number.

Then, you can look up what mass of Jupiter /really/ is, and work out from that how close you are :-)

The really cool part, is where you compare your results against "real" results, and explain *why* yours were different.

ballaratdragons (Ken) · #18 15-05-2007, 10:42 PM

Quote:

Originally Posted by freespace

The really cool part, is where you compare your results against "real" results, and explain *why* yours were different.

Coz 'the real results' are wrong

bojan · #19 16-05-2007, 08:40 AM

Quote:

Originally Posted by ballaratdragons

and here's another project using Mylar as a telescope for measuring infra-red.

http://home.freeuk.com/m.gavin/flux.htm

Gee.... I wanted to patent something like this back in '60... and was thinking "naaah, not worth the effort.."
I also did not have access to such a huge piece of mylar.... life is cruel :-)

This may also be a good heat collector for alternative power source...

bojan · #20 16-05-2007, 08:44 AM

Apart from Jupiter moons orbits, you could try to calculate the orbital elements of one of asteroids (Vesta, for example) from couple of observations (measurement of positions).
If you are interested, I can send you a BASIC program that does that (it is developed by Erich Karkoschka in '70ies, to be used during Astronomy Summer school held in Europe in those days, for exactly that sort of things. It is also useful for newly discovered comets etc). You could try to convert it into C++ :-)