Astronomy

[Xenophon PCDGS]

My eldest son has a Russian-built telescope that he bought to further his interest in astronomy. It is a Ylena 150mm F/14.2 Maksutova-Cassegrain...,I think this is what he said, when I rang him, when I saw this thread. I was always interested in the subject of astronomy and we have the world-famous radio telescope at Jodrell Bank not so far from us in our part of Cheshire, which my sons always wished to visit when they were young, which had a Planetarium. I still have a very basic telescope that I bought very many years ago from a photographic shop in Wilmslow, that sufficed for the boys whilst they were at St.Ambrose College in Hale Barns. I have a computer programme called Red Shift 4, that has much general astronomical information upon it. Unfortunately, my eyes are now not as good as they used to be, but I would always recommend any young person to take up astronomy both as a subject and as a hobby.

 

[Class172]

I would recommend Stellarium as an excellent planetarium software; it's free as well.

 

[Class172]

Orion is now visible on the evening, however the streetlamp at the front of my house obscures its view until half nine currently.

Jupiter and the moon have been very good to look at recently, with Tycho crater visible in excellent contrast (if a bit bright at gibbous phase). I have also seen Albireo (β Cyg) which was very clear; you could easily make out the two orange and blue stars.

 

[Peter Mugridge]

Minor meteor shower coming up: The Ursids on the night of 22nd / 23rd December, only 10 an hour but no moonlight interfering.

And a major one: The Quadrantids on the night of 3rd / 4th Jan, maximum is at 06.00 on the 4th; Moon sets at 03.30 so is a very favourable shower which is known to produce coloured meteors ( yellow and blue ). At maximum the usual rate is 80 an hour, but it's a narrow maximum rather than spread out all night.

 

[LE Greys]

I've been tracking Jupiter for months now, just about the only thing you can see under Aberdeen's city lights (discounting the Moon) although I have caught the odd glimpse of Sirius recently. Haven't had much of a chance to have a peep at the moons, which I can just make out with my big binoculars, because it's not been dark enough. I do have a telescope, a crummy 3in refractor with a prism, which gives rubbish definition and makes everything look faded. Still managed to see the Martian ice caps with it once, though.

BTW, a question. Would a bright flash in the northern sky in a Scottish city at 16:30 in the evening be the aurora borealis? Might have been lightning, but there was no thunder and no storm in the area. A big explosion would have made the news. Can't think of any other explanation, so have I seen an aurora?

 

[Class172]

Hmmm… intriguing, I wonder what it was. Unless it was glowing (generally green) and could see swirling patterns in the sky, then I doubt it was the aurora bolearis; could be wrong though.

Just thinking, could it have been ball lightning, a strange phenomena which does produce a bright flash?

 

[LE Greys]

Hmmm… intriguing, I wonder what it was. Unless it was glowing (generally green) and could see swirling patterns in the sky, then I doubt it was the aurora bolearis; could be wrong though.

Just thinking, could it have been ball lightning, a strange phenomena which does produce a bright flash?

Big and blue. There was a bit of cloud, but not sign of lightning.
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Well, ROSAT is due to come down shortly so it's ding ding round 2 for possible observation of a re-entry!

That's a bit worrying, those have nuclear power plants. They are supposed to eject them into a higher orbit, but they sometimes don't, and one scattered radioactive material over Manitoba back in the nineties.

 

[Peter Mugridge]

That's a bit worrying, those have nuclear power plants. They are supposed to eject them into a higher orbit, but they sometimes don't, and one scattered radioactive material over Manitoba back in the nineties.

Don't worry, that came down weeks ago now.
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BTW, a question. Would a bright flash in the northern sky in a Scottish city at 16:30 in the evening be the aurora borealis? Might have been lightning, but there was no thunder and no storm in the area. A big explosion would have made the news. Can't think of any other explanation, so have I seen an aurora?

Not an aurora, if it was a sudden bright flash like a distant explosion it was probably a bright meteor ( called a fireball ).

If it was a sort of slower metallic flash, it was very likely an Iridium flare. These can be predicted; look in here: http://www.heavens-above.com/ ( set your location from the drop down menus before saving to favourites ).

 

[LE Greys]

Not an aurora, if it was a sudden bright flash like a distant explosion it was probably a bright meteor ( called a fireball ).

If it was a sort of slower metallic flash, it was very likely an Iridium flare. These can be predicted; look in here: http://www.heavens-above.com/ ( set your location from the drop down menus before saving to favourites ).

That's interesting, it might well be, looked just about the right colour for an Iridium flare. I remember it being very big, lighting up a significant portion of the horizon. That's why I thought it was lightning initially, sheet lightning, but there was absolutely no other evidence of a storm, just low clouds.

 

[Peter Mugridge]

No, that wouldn't be an Iridium flare if it lit up that much - it was almost certainly a fireball.

An Iridium flare is just like a satellite crawling across the sky, but is only visible for a short time ( typically 30 - 40 seconds of which 5 - 10 seconds will be the actual flare ) except for being much brighter than a normal satellite - the brightest ones are magnitude -8, which is roughly similar to watching an airliner with the landing lights on.

 

[12CSVT]

Want to hear some 'facts' about astronomy ?

Have a listen to this - The Galaxy Song (Monty Python's Meaning of Life)

http://www.youtube.com/watch?v=TvD4N70V5mE

 

[Eagle]

I do actually have a telescope gathering dust (it's tiny—50 mm refractor). Should dig it out some time; it was really good for looking at planets.

I do most of my stargazing on my computer, on a freeware program called Stellarium which I'd recommend to anyone.

 

[Class172]

I stellarium!

 

[Xenophon PCDGS]

Can someone give any currently known definate information concerning two asteroids :-

QQ47 and Apophis

 

[Class172]

99942 Apophis
2003 QQ47

It is unlikely that any of these objects will hit earth, though I hope that Apophis doesn't pass through the 'gravitational keyhole' as that will cause an impact on the next approach, but that is unlikely.

 

[Class172]

Anyone else watching Astronomy LIVE??

 

[Greenback]

Anyone else watching Astronomy LIVE??

Yes, I haven't seen all of it, but the bits I have seen have been very good. I learnt more about gravity in ten minutes last night than I ever did in school!

 

[Class172]

It has been a very good series so far; I am looking forward to the exoplanets discussion tonight. We were discussing about it in astonomy at school today - my homework was to do with exoplanets also.

Soon be going down to turn the TV on...

 

[Greenback]

It has been a very good series so far; I am looking forward to the exoplanets discussion tonight. We were discussing about it in astonomy at school today - my homework was to do with exoplanets also.

Soon be going down to turn the TV on...

I saw a fair bit more tonight, very interesting it was too, although I remain a bit confused as to whether there are 9 planets in the solar system or only 8! When I was a lad it was definitely 9!

 

[Eagle]

I make it 13.

 

[Class172]

Does this include:
Mercury
Venus
Earth
Mars
Ceres
Vesta
Jupiter
Saturn
Uranus
Neptune
Pluto
Eris
Haumea
Sedna
…by any chance.

 

[Ivo]

I like how one of you has said 13 and the other has listed 14

I used to love astronomy, but my school didn't offer it as a GCSE until I had already left - and there was literally one week's content in the combined science syllabus, and then it was right at the end of the course

 

[Greenback]

I still don't know the answer then...!

 

[Peter Mugridge]

It's 8 planets* officially. The others are known by various other classifications such as dwarf planets, Kuiper belt objects, etc etc.


*Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

 

[Eagle]

Plus the dwarf planets Ceres, Pluto, Makemake, Haumea and Eris

(Vesta and Sedna don't count because they're not spherical.)

 

[Class172]

Plus the dwarf planets Ceres, Pluto, Makemake, Haumea and Eris

(Vesta and Sedna don't count because they're not spherical.)

I was just listing what you may have been thinking of. I know that many are classified as Dwarf Planets — you say Sedna and Vesta aren't spherical, neither is Haumea (or is it makemake) that is extremely oblate.

 

[Greenback]

This is what I was wondering, are dwarf planets also planets, or a seperate category? I'm sure they mentioned 8 planets in the solar system on the show, so does that indicate that dwarf planets are not counted officially?

 

[Peter Mugridge]

Well... yes and no; the 8 planets are classified as planets, the others are classified as dwarf planets. That's a completely different thing.

To say the dwarf planets are planets is a bit like saying the class 08s are class 47s...

They're still locomotives. The dwarf planets are still big rocks going round the Sun...

 

[Class172]

Well I suppose it would cause a load of confusion and textbooks would have to be majorly edited if we suddenly said the Solar System had about 14 planets (including dwarf planets). I think for a dwarf planet to be designated planet it needs to have cleared it's neighbouring region of space, on top of the dwarf planet guidelines, something which Pluto failed to do, being surrounded by hundreds of other Kuiper Belt objects.

 

[Xenophon PCDGS]

BBC News website reported that the 11 metre diameter asteroid called BX34 actually passed within 60,000km of the earth yesterday at 1600 GMT, which is quite close.