Friday, 30 November 2007

S194: Astronomy practicals

Put me firmly in the class of fair weather astronomers...

I have borrowed a fairly basic reflecting telescope to do some observing. Last Friday was an excellent night to try it out. Although I live in a rather light polluted area, the night sky was crisp and clear. Bright pin pricks of light could clearly be seen through the upstairs window. I went downstairs and stepped outside for a better look, and after a sharp intake of breath, I dashed back in - COLD COLD COLD!!
Observation was terminated before it had really begun.

However, last night, there were only a couple of minor squibs of cloud about, but on the whole things looked pretty good, and the temperature outside was much better. This was much more the way to do it, OK so it would require a coat, but not necessarily Arctic survival gear.

So I went back inside, and lugged out the telescope, set up the tripod, picked the least powerful of the lenses and found Mars with the spotter scope. After a while, I managed to get it well fairly centred, but realised that the cross-hairs which seem like such a good idea, when viewed at night, are black on a black background, with little light, are not in the slightest bit visible in the dark! Even with the least powerful eyepiece, the image has to be pretty much in the centre of the spotter scope to find it.

I went back in to get a more powerful eyepiece, there is only so much you can juggle in one trip...
I installed the eyepiece, and after a bit more hunting managed to re-find Mars, and it agreeably became a small disc, jumping around all over the place as I tried not to touch the telescope and induce any more wild oscillations. Have you ever seen Lissajous Figures on an oscilloscope (do they still use those?) - well that's pretty much what Mars looked like most of the time.

Comet 17P/Holmes - nto that I'd recognise it...
OK - time to try something a bit more tricky, how about that comet 17P/Holmes. I could be like a real astronomer, and casually drop into the conversation my cutting edge observations on the night sky. "Have you seen 17P/Homes perchance? No - oh what a shame..."

I'd already loaded the data into Stellarium and so fired up the laptop on the kitchen table. OK - so its approximately overhead at the moment. If I starts a Mars, and a line up, past Cassiopeia and a bit to the right, yeah that should work.

Went back outside with a couple of the constellations roughly memorised... and WHAT THE...??????

The night sky was now completely overcast, not a single celestial object visible! In the 3-4 minutes I'd been inside a cloud layer had just appeared, as if from nowhere, covering from horizon to horizon. I swear, it was like being on a prank TV program! How did that happen? I went inside and out again to see if I'd been mistaken, but no - complete overcast.

I left the telescope out, and checked occasionally, and about an hour later I could see Mars again in a clear patch of sky. Maybe the overcast was a transient feature. I refocused and re-centred, and then ran inside to get the highest mag. eyepiece. A quick squint to see if it was still centred, and as I watched it there, it slowly and majestically faded completely from view! The overcast was back! This time for good - I wondered if there was anything on TV...

Tuesday, 20 November 2007

S194: Astronomy

Wow this is a nice gentle course after S204 and A251!
The box came, and in it was:
  • A study guide
  • Introducing astronomy text book
  • A Planisphere - a device to help you find stars (and not planets)
  • CD-ROM
  • Handbook
  • How to get help book
  • Applications CD
The planisphere is fun to play with, but for me there is a copy of stellarium on the CD-ROM which is much better. I don't bother loading it as its slightly out of date and installed the most current version instead. The CD-ROM also has a collection of images of various stars and planets and some data sheets giving info about all sorts of things in the form of data.

I read through the course book which was a fairly light read compared to more recent texts. Its just over a 100 pages long, and for someone who has done other science courses there is a fair degree of familiar material in it. Stuff like scientific notation, errors, SI units and that sort of thing. This being an entry level course, it has to be covered of course.
The course covers:
The sun, the planets, stars, galaxies, extraterrestrial life, and the universe including the big bang. It doesn't really go into much depth in any of them. The rocky planets are covered in a few paragraphs, as are the gas giants. There is not that much on the different types of stars and only a bit more on the types of galaxies.

After I had finished the book - which took just under two weeks, and looked at a few of the images I was ready to tackle the ECA. I had thought this course was particularly easy. Far less reading than the planets course for instance.

However, the ECA was like a bolt from the blue. It started to ask questions I had no idea how to answer at first glance. Questions about the temperature of the inner and outer parts of the Suns transition zone - the what? I couldn't remember reading much about this if anything, and looking back at the book there is virtually nothing in the book about it. I wondered if there was a second book I should have read, or something was missing. However when looking at the annotated images there is a fuller description of many things there. What's more some of the data files also have answers in them. So its not so much being able to find the answers in the book, but scavenging through all the material you are given to find the answers. It quickly turns into somewhat of a scavenger hunt!

My respect for the course goes up rather after having to turn the course materials inside out to find all the answers! It took me two nights to complete the ECA, one of them lasting until past midnight. However it must be in the running for my fastest ever course. It officially started on the 17th Nov, and I had he ECA completed by the 21st! Obviously the materials arriving early gave me longer than that, but it makes a nice story.

It also gives me plenty of breathing space for the A251 ECA which I want to get clear before my next course starts - at the scary sounding 3rd level.

Thursday, 15 November 2007

A251: TMA-3

Another TMA coming down the road.

This time there is only a single question, but with a degree of latitude. Compare and old world empire with a new world empire. The course has been focusing on empires and has been through most of the ancient empires by now. This has meant a lot of reading, lots and lots.

The first generally recognised empire was the Akkadian empire of which there aren't too many remains of, but lots of echoes. We then go through more empires in the middle east, China, Egypt, middle and south America. Then back to the more commonly known ones like Greek and Roman. It is all quite interesting, but the amount of reading makes it quite a lot of work, and it seems from the forums that I'm not the only one who is skipping lightly through some of the sections that they don't intend to write about in the TMA.

Anyway, on to the TMA. Quite a lot of people seem to be picking the Romans as the old world empire - which is fair enough. There is a lot of material on that empire and plenty of reference material too. I decide to pick the Persians though, partly because I wanted to learn a bit more about them, and als partly just to be a bit different.

Of the new world empires there is much less choice. Aztecs or Incas is really the main choices, with a possible argument over whether the Olmec was an empire or not. The consensus is that the Mayan civilisation wasn't an empire.

Anyway, whichever you pick 1500 words of comparative text is required, together with references.

Tuesday, 6 November 2007

A frenzy of course decisions

Its getting nearer to the next start date for courses, and with only the A251 on the go at the moment I'm looking for what to do next.

First, there are the 3rd level biology residential courses. If I want a biology degree, I have to take two of these, and the places fill up fast. So I booked at 7:30am on the opening day via the internet to ensure my place. So that's one down, SXR376 Molecular basis of human disease, but it is not until next July. To go with that I settle on a particular 3rd level main course, S320 - infectious diseases, which I think should be interesting and possible.

In the meantime, I'm missing my science, so I signed up for the short course on astronomy, S194.

This way leads madness as I find there is a certificate in astronomy which involves using radio telescopes at Jodrell Bank, and another certificate that includes a couple of courses I was interested in. Oh dear, I could be here for many years at this rate!