Last night was one of the better nights of the year so far. Well actually it was the first night this year I've managed to get my 6SE out and see some objects. And the first chance I've had since the infamous night of the 11th of December when it was crystal clear but I got home too late. My wife also joined me for some of the early observations and she was as impressed as I was with what we saw.
Although it was relatively clear, and surprisingly warm, there were clouds moving across so we had to wait a little while but managed to get a reasonable alignment on Betelgeuse and Rigel - the two stars I could easily identify. One object I've wanted to see for some time is the Orion Nebula (M42), so that was the first thing we looked at. Wow! That whole region is full of stars and once you know where to look for it, the nebula is even visible through the 8x20 monocular I have. A decent pair of 10x50 binoculars would be more than enough to see it well.
Mars was pretty high by this time, about 9pm, so I could see it well as a bright sand-coloured dot. For some reason, and I have no idea why, I didn't swap to my 15mm eyepiece to get more magnification and stayed with the 25mm I use for alignment. Very odd.
The onto the Pleiades, small but impressive. And then it all went horribly wrong when I kicked the tripod. I managed to get the Pleiades back into alignment and then realigned on Rigel and Betelgeuse but from that point onwards my GOTOs were a bit off so apart from looking for a few DSOs I used the rest of the time I was out to identify stars for later observing sessions - Castor and Pollux, Procyon and Aldebaran - which worked wll enough. And then it started to get cold so I packed up.
A couple of things occurred to me. First I need to get some form of dictaphone so that I can record observations. I know I looked at M34, M35 and M36 but I can't really recall what I saw so need to take notes. Second I can only really look at objects in the eastern sky as the glow from central London is pretty disruptive. Which is OK because there's lots of interesting stuff there at the moment but it would be nice to have the option. Anyone for switching the lights off in Canary Wharf?
Sunday, January 6, 2008
Tuesday, December 11, 2007
Clearest night of the year
I've not seen a night this clear for the last six months. And I've just got home from going out to dinner and it's too late to get my scope out. Gutted!
Thursday, September 27, 2007
Why do I have a telescope?
Back in April I went on an Open University summer school to Mallorca to do some astronomy. It was an excellent course, by far the best the OU do and even more fun because I ended up passing with a distinction. The course description is here and although you need to organise travel, accommodation is all included in the price.
What was interesting though was that you don't spend a lot of time looking through a telescope, well only twice over the whole week. That's because while it's a course that works with visible light, all of it is done using some very expensive CCD cameras or a spectrograph attached to laptops. So there we were, using equipment that probably cost a total of something like £15,000 in purpose built domes under clear dark skies. And it was nice and warm as well. We even saw a meteor shower. And while it was hard work - you start at 6PM and work through to closing the dome down at 4AM the following morning - it was also huge fun.
And that's the problem, Astronomy's fun and addictive. Once you do it, you want to do it again.
What was interesting though was that you don't spend a lot of time looking through a telescope, well only twice over the whole week. That's because while it's a course that works with visible light, all of it is done using some very expensive CCD cameras or a spectrograph attached to laptops. So there we were, using equipment that probably cost a total of something like £15,000 in purpose built domes under clear dark skies. And it was nice and warm as well. We even saw a meteor shower. And while it was hard work - you start at 6PM and work through to closing the dome down at 4AM the following morning - it was also huge fun.
And that's the problem, Astronomy's fun and addictive. Once you do it, you want to do it again.
Monday, September 24, 2007
Alignment oddities...
My 6SE had something of a fit over the weekend. I have no idea what I did wrong or what I did to resolve it but for the first part of the evening, it was behaving very oddly.
I normally use Polaris and Altair to perform an alignment. These combinations are pretty for me to identify with one to the north, I'll leave you to guess which, and one pretty much to the south and both at different altitudes. At the start of the evening, my CN16 GPS add-on was behaving erratically and seemed unable to link properly. So I overrode it, set the time manually and got started. Polaris went OK but when I went to Altair in the list of named stars, it wasn't there. So I retried on Dubhe and got aligned, though as these two stars are pretty close together it wasn't too good an alignment.
Then I noticed that some other objects weren't listed - the Ring Nebula and the Moon for two - so something odd seemed to be going on. So I powered off the scope, reset it to level pointing north, put the GPS on the top and started again. This time it got the GPS link first time, the alignment stars included Altair and when aligned, the Ring Nebula was there in the list of named objects and the moon in the Solar System objects.
A very peculiar event.
The rest of the evening went very well. I saw all my old favourites and even Uranus made a short appearance as a very small disk, slightly offset in the FOV but still definitely visible. A quick look at the moon showed a nice focused image with very visible craters - I just couldn't fit it all in the FOV. Then I had my next odd event, the moon lost focus. So I switched to Albireo and checked, focus was fine. The looked at the front of the scope and the Schmidt plate, which was covered in a fine coating of water. Sometime while I was looking at the moon we hit the right temperature for dew to form and with no heating on my Schmidt plate, that was it for the evening.
So a couple of interesting views, some problems - one with a clear cause and the other hard to explain - and more progress in observation. Now all I need to do is get hold of a small 12v hair dryer to keep my objective dry :)
I normally use Polaris and Altair to perform an alignment. These combinations are pretty for me to identify with one to the north, I'll leave you to guess which, and one pretty much to the south and both at different altitudes. At the start of the evening, my CN16 GPS add-on was behaving erratically and seemed unable to link properly. So I overrode it, set the time manually and got started. Polaris went OK but when I went to Altair in the list of named stars, it wasn't there. So I retried on Dubhe and got aligned, though as these two stars are pretty close together it wasn't too good an alignment.
Then I noticed that some other objects weren't listed - the Ring Nebula and the Moon for two - so something odd seemed to be going on. So I powered off the scope, reset it to level pointing north, put the GPS on the top and started again. This time it got the GPS link first time, the alignment stars included Altair and when aligned, the Ring Nebula was there in the list of named objects and the moon in the Solar System objects.
A very peculiar event.
The rest of the evening went very well. I saw all my old favourites and even Uranus made a short appearance as a very small disk, slightly offset in the FOV but still definitely visible. A quick look at the moon showed a nice focused image with very visible craters - I just couldn't fit it all in the FOV. Then I had my next odd event, the moon lost focus. So I switched to Albireo and checked, focus was fine. The looked at the front of the scope and the Schmidt plate, which was covered in a fine coating of water. Sometime while I was looking at the moon we hit the right temperature for dew to form and with no heating on my Schmidt plate, that was it for the evening.
So a couple of interesting views, some problems - one with a clear cause and the other hard to explain - and more progress in observation. Now all I need to do is get hold of a small 12v hair dryer to keep my objective dry :)
Friday, September 14, 2007
Doubles and clusters
Over the last week or so I've had time to look at a number of different objects, mainly double stars such as Albireo, the Double Cluster and a number of different nebulae. And to be honest, I still say you can't beat a good double with two different coloured stars, like the orange and blue of Albireo.
I suppose a lot of it's the visual impact. A good double is clear and obvious where with my current setup, even the Ring Nebula is still small and inconspicuous. Perhaps a smaller eyepiece is called for, and the greater magnification that will bring.
But still, seeing the Double Cluster in all its glory is a seriously impressive sight and one that I'm more than happy to go back to again and again.
I suppose a lot of it's the visual impact. A good double is clear and obvious where with my current setup, even the Ring Nebula is still small and inconspicuous. Perhaps a smaller eyepiece is called for, and the greater magnification that will bring.
But still, seeing the Double Cluster in all its glory is a seriously impressive sight and one that I'm more than happy to go back to again and again.
Tuesday, September 11, 2007
Progression and successes
One of the problems with the Celestron system is backlash in the gears. That's where there's a certain amount of slack in the gear train which appears to the user as a delay between the button being pushed and the scope starting to slew. Having said that, backlash isn't a problem, if you do the alignment right.
With the default settings, you need to make the same movements to complete the alignment as the scope does when it moves to a target. This means the final alignment movements must be up and to the right. If you overshoot, go back the other way past the centre point and then re-centre the star. Originally I had been aligning down and to the right which meant that gotos ended up with the target at the bottom of the field of view on the supplied 25mm Plossl. Aligning up and right placed the target in the centre of the FOV. Much better. So much so that I was able to switch to the 15mm eyepiece I bought with the scope and find all of the objects in the centre of the smaller FOV.
An hour later, running around the sky looking at a range of objects in different parts of the sky, GOTOs were still amost centred, drifting perhaps a bit low and to the left but not even close to the edge of the FOV. A most satisfying evenings viewing.
With the default settings, you need to make the same movements to complete the alignment as the scope does when it moves to a target. This means the final alignment movements must be up and to the right. If you overshoot, go back the other way past the centre point and then re-centre the star. Originally I had been aligning down and to the right which meant that gotos ended up with the target at the bottom of the field of view on the supplied 25mm Plossl. Aligning up and right placed the target in the centre of the FOV. Much better. So much so that I was able to switch to the 15mm eyepiece I bought with the scope and find all of the objects in the centre of the smaller FOV.
An hour later, running around the sky looking at a range of objects in different parts of the sky, GOTOs were still amost centred, drifting perhaps a bit low and to the left but not even close to the edge of the FOV. A most satisfying evenings viewing.
Wednesday, September 5, 2007
First light, well sort of
After a brief flirtation with an ETX80 (I know, it was a moment of madness followed by a very quick return to the vendor) I "saw the light" and bought a NexStar 6SE from Sussex Astronomy on the 15th of June. What with the combination the very, very, poor weather we've had in the UK this year, the vagaries of AA battery power and a steepish learning curve (finding out what to look at), tonight was effectively the first light for my NexStar. So I thought I'd share my experiences with this rather nice piece of engineering :)
I suppose I should start with what I bought. A Celestron NexStar 6SE and an additional 15mm Meade 4000 series eyepiece. The kind chap at Sussex Astronomy wanted to sell me a Power Tank but had none in stock. Oh how I wish he'd had some in stock.
A period of few-and-far-between attempts to use my scope followed. Lots of AA batteries died in this cause, and not a few spare electrons in the cause of finding out what timezone I'm in and how to set my proper location on the handset. £200 spent on a CN-16 GPS unit solved the latter while a birthday present Power Tank, courtesy of the birthday fairy who also bought a copy of Turn Left at Orion, solved the former.
So tonight I finally had all the pieces I need to use the scope I bought nearly three months ago properly - the scope, a proper power supply, knowledge of where I am and what time it is and most importantly a better idea of what I'm looking at.
So out I go. I can see Altair but Arcturus is hidden by a chimney pot. One of mine. It will have to go. (Who said this was a cheap hobby? Adding building work to GPS units does not qualify as cheap). OK, I can see Dubhe. So align on Dubhe then Altair. Then off to Dubhe for a check. Spot on azimuth but right at the bottom of my 25mm eyepiece. Move Dubhe up to the middle, swap to the 15mm Meade eyepiece and replace the first alignment with this one. Nice.
Then off to the double Albireo. Same position as Dubhe was but still in view. A bit of a move up and I can see the different colours of the stars. Orange/red low-left and blue high-right. Oh yes indeed that's nice.
Now the Ring Nebula. Back with the 25mm and it's in the finder. A quick move to the middle, switch to the 15mm and there it is. Nice, just don't look right at it or it disappears in your blind spot. The same for the Cat's Eye which is a bit smaller than the Ring and again in my blind spot unless I'm careful. Or so it seems.
Having done well so far I try a few other objects which don't work too well - they're right over the orange glow of central London and a bit dim. But then go for the Double Cluster, through the trees and just below Cassiopeia. to my North. Oh. My. God.
That's very nice. Very, very nice. Slightly low and to the right at first and the 25mm eyepiece is better than the 15mm because it's so big. Maybe a 30mm or 40mm will be better? But I'e come to the conclusion that I'm an open cluster and doubles man.
At this point I call out my wife (my sponsor and the provider of the power tank and copy of Turn Left at Orion) and daughter out into the back garden and go through a quick show. Albireo goes down well. The Ring Nebula gets an OK reaction. The Double Cluster's a real winner though, loads of oohs and aaahs.
So there you go. First light with my nearly three month old 6SE.
I suppose I should start with what I bought. A Celestron NexStar 6SE and an additional 15mm Meade 4000 series eyepiece. The kind chap at Sussex Astronomy wanted to sell me a Power Tank but had none in stock. Oh how I wish he'd had some in stock.
A period of few-and-far-between attempts to use my scope followed. Lots of AA batteries died in this cause, and not a few spare electrons in the cause of finding out what timezone I'm in and how to set my proper location on the handset. £200 spent on a CN-16 GPS unit solved the latter while a birthday present Power Tank, courtesy of the birthday fairy who also bought a copy of Turn Left at Orion, solved the former.
So tonight I finally had all the pieces I need to use the scope I bought nearly three months ago properly - the scope, a proper power supply, knowledge of where I am and what time it is and most importantly a better idea of what I'm looking at.
So out I go. I can see Altair but Arcturus is hidden by a chimney pot. One of mine. It will have to go. (Who said this was a cheap hobby? Adding building work to GPS units does not qualify as cheap). OK, I can see Dubhe. So align on Dubhe then Altair. Then off to Dubhe for a check. Spot on azimuth but right at the bottom of my 25mm eyepiece. Move Dubhe up to the middle, swap to the 15mm Meade eyepiece and replace the first alignment with this one. Nice.
Then off to the double Albireo. Same position as Dubhe was but still in view. A bit of a move up and I can see the different colours of the stars. Orange/red low-left and blue high-right. Oh yes indeed that's nice.
Now the Ring Nebula. Back with the 25mm and it's in the finder. A quick move to the middle, switch to the 15mm and there it is. Nice, just don't look right at it or it disappears in your blind spot. The same for the Cat's Eye which is a bit smaller than the Ring and again in my blind spot unless I'm careful. Or so it seems.
Having done well so far I try a few other objects which don't work too well - they're right over the orange glow of central London and a bit dim. But then go for the Double Cluster, through the trees and just below Cassiopeia. to my North. Oh. My. God.
That's very nice. Very, very nice. Slightly low and to the right at first and the 25mm eyepiece is better than the 15mm because it's so big. Maybe a 30mm or 40mm will be better? But I'e come to the conclusion that I'm an open cluster and doubles man.
At this point I call out my wife (my sponsor and the provider of the power tank and copy of Turn Left at Orion) and daughter out into the back garden and go through a quick show. Albireo goes down well. The Ring Nebula gets an OK reaction. The Double Cluster's a real winner though, loads of oohs and aaahs.
So there you go. First light with my nearly three month old 6SE.
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