Sunday, 30 May 2010
Friday, 28 May 2010
Time of day and a nasty stain
It really makes a difference. Photograph something at midday and compare it to a picture taken at sunset or sunrise.
These are both pictures of Keck 2 with the Haleakala volcano on Maui in the background. The former was taken during a little time off I had while watching our telescope being taken apart in the middle of the day, the latter while I was up observing earlier in the month and took a few minutes from work to take in the sunset.
What I really want to know, though, is what's that brown stain on the Keck 2 dome in the first picture. Maybe it's not visible in sunset shots and has been there forever, but I haven't seen it before - daytime or at sunset.
These are both pictures of Keck 2 with the Haleakala volcano on Maui in the background. The former was taken during a little time off I had while watching our telescope being taken apart in the middle of the day, the latter while I was up observing earlier in the month and took a few minutes from work to take in the sunset.
What I really want to know, though, is what's that brown stain on the Keck 2 dome in the first picture. Maybe it's not visible in sunset shots and has been there forever, but I haven't seen it before - daytime or at sunset.
Wednesday, 26 May 2010
Moving day
Yesterday I mentioned that the telescope was being taken apart and the primary mirror being moved to the CFHT to be realuminised. Today was the big moving day and I have a few snapshots of the move.
Above, the primary mirror is lifted, very carefully, off its mount revealing the complicated mechanisms we don't often get a chance to see. At the top right is the centre of the mirror with its ventilation system for mirror cooling. We blow cold air over the primary mirror during the day to keep it cold and matched to the anticipated air temperature at night. This has had a huge and positive effect on our image quality, especially at the start of the night. The stuff around it are simply reflections of the telescope structure above.
The primary is slowly moved away from the mount revealing even more of the structure it normally rests on. The rings of small devices are the actuators we use to bend the mirror by tiny amounts to correct for the effects of gravity as we slew the telescope around the sky.
It's a painstakingly slow process but this is not cheap optics like my camera. Several tonnes of glass are gently being moved to the truck which will take it over to the CFHT for its new coating. There is no replacement for the primary mirror, we can't afford to make any mistakes.
Looks a bit like a flying saucer, doesn't it?
It's on the truck and now a protective cover is placed on top for the few hundred yards journey to the CFHT. The whole process shown in the pictures took a couple of hours, but it's already three days into the project just to get this far. This isn't something you can do quickly.
With the primary mirror on its way I took the opportunity to take a few pictures of the mount and the actuators. Getting these to perform correctly with WFCAM has been a large part of my job over the years and it was a good chance to get a close look at them before they were all tested later in the day. As you can probably tell from the valves, they are operated pneumatically under some very precise control via software - a system I've come to understand rather well!
A closer look at one of the actuators and pneumatic line. The primary rests on top of these and they move up and down as the telescope moves in order to reshape the primary mirror and keep image quality consistent no matter where we're looking in the sky.
I don't know what that material is on top of the actuators but it looks like cork! I'll have to ask.
Finally, the top-end or the mechanism that supports the secondary mirror which is usually at the top of the telescope but now sits in the lab. This is another part of the telescope that I've been responsible for over the last few years as we use it to move the secondary mirror to compensate for gravitational-induced flexure in the WFCAM instrument as well as compensating for atmospheric turbulence (often moving and adjusting its position 100 times a second). It's been giving us the odd problem recently so we'll be having a close look at it over the next couple of weeks.
There's been a lot of effort by our engineering crew to make this project work and there's more to come, but it was great to see yet again what a professional and hard-working bunch of people they are. And a lot of fun to work with!
Above, the primary mirror is lifted, very carefully, off its mount revealing the complicated mechanisms we don't often get a chance to see. At the top right is the centre of the mirror with its ventilation system for mirror cooling. We blow cold air over the primary mirror during the day to keep it cold and matched to the anticipated air temperature at night. This has had a huge and positive effect on our image quality, especially at the start of the night. The stuff around it are simply reflections of the telescope structure above.
The primary is slowly moved away from the mount revealing even more of the structure it normally rests on. The rings of small devices are the actuators we use to bend the mirror by tiny amounts to correct for the effects of gravity as we slew the telescope around the sky.
It's a painstakingly slow process but this is not cheap optics like my camera. Several tonnes of glass are gently being moved to the truck which will take it over to the CFHT for its new coating. There is no replacement for the primary mirror, we can't afford to make any mistakes.
Looks a bit like a flying saucer, doesn't it?
It's on the truck and now a protective cover is placed on top for the few hundred yards journey to the CFHT. The whole process shown in the pictures took a couple of hours, but it's already three days into the project just to get this far. This isn't something you can do quickly.
With the primary mirror on its way I took the opportunity to take a few pictures of the mount and the actuators. Getting these to perform correctly with WFCAM has been a large part of my job over the years and it was a good chance to get a close look at them before they were all tested later in the day. As you can probably tell from the valves, they are operated pneumatically under some very precise control via software - a system I've come to understand rather well!
A closer look at one of the actuators and pneumatic line. The primary rests on top of these and they move up and down as the telescope moves in order to reshape the primary mirror and keep image quality consistent no matter where we're looking in the sky.
I don't know what that material is on top of the actuators but it looks like cork! I'll have to ask.
Finally, the top-end or the mechanism that supports the secondary mirror which is usually at the top of the telescope but now sits in the lab. This is another part of the telescope that I've been responsible for over the last few years as we use it to move the secondary mirror to compensate for gravitational-induced flexure in the WFCAM instrument as well as compensating for atmospheric turbulence (often moving and adjusting its position 100 times a second). It's been giving us the odd problem recently so we'll be having a close look at it over the next couple of weeks.
There's been a lot of effort by our engineering crew to make this project work and there's more to come, but it was great to see yet again what a professional and hard-working bunch of people they are. And a lot of fun to work with!
Tuesday, 25 May 2010
Spring cleaning
The title isn't entirely accurate, it's more of a spring refurbishment. UKIRT is currently closed because the primary mirror is about to be realuminised.
Telescope mirrors need to reflect light as efficiently and accurately as possible. In most cases the accuracy comes from the initial production of the mirror but the reflectivity can change over time and that's due to a number of factors. Telescopes like UKIRT use a thin coating of aluminium (or aluminum if you're from the USA) which is highly reflective in the infrared but the local weather and environment erodes this surface and it needs to be renewed every few years. Unfortunately UKIRT doesn't have the facilities to do this itself so over the last couple of decades we've sent the primary mirror to the CFHT for coating as they have a coating tank suitable for the tonnes (tons!) of glass we send their way.
Not that long ago we were considering coating the primary with silver. It would have been more expensive than using aluminium but bear in mind we're only talking about a thickness of a few hundred microns and in general the process is the same. In the end we backed out of this because although silver is better in the infrared, it really only benefits wavelengths longer than around 2.5 microns and our current survey only goes to about 2.3 microns, so the benefits would have been limited. It would also have meant using a new facility for the process and at the time silver coating were still experimental with some ambiguous results, so we stuck with the old but tried and tested method.
Tomorrow I'm back at the summit again, but during the day. The telescope will have been taken to pieces and it'll be interesting to see what remains. Our current instrument, WFCAM, will have been removed from above the primary to allow us to remove the mirror and it'll allow a look at the guts of one of the most productive and successful telescopes in modern astronomy.
I took a shot of WFCAM from inside the dome a couple of weeks ago and you can see it above. I'll try and take a couple of shots tomorrow so you can see the difference. I'm back up to recommission the telescope in early June so hopefully it'll look as though nothing ever happend - except the primary will look beautifully pristine!
Telescope mirrors need to reflect light as efficiently and accurately as possible. In most cases the accuracy comes from the initial production of the mirror but the reflectivity can change over time and that's due to a number of factors. Telescopes like UKIRT use a thin coating of aluminium (or aluminum if you're from the USA) which is highly reflective in the infrared but the local weather and environment erodes this surface and it needs to be renewed every few years. Unfortunately UKIRT doesn't have the facilities to do this itself so over the last couple of decades we've sent the primary mirror to the CFHT for coating as they have a coating tank suitable for the tonnes (tons!) of glass we send their way.
Not that long ago we were considering coating the primary with silver. It would have been more expensive than using aluminium but bear in mind we're only talking about a thickness of a few hundred microns and in general the process is the same. In the end we backed out of this because although silver is better in the infrared, it really only benefits wavelengths longer than around 2.5 microns and our current survey only goes to about 2.3 microns, so the benefits would have been limited. It would also have meant using a new facility for the process and at the time silver coating were still experimental with some ambiguous results, so we stuck with the old but tried and tested method.
Tomorrow I'm back at the summit again, but during the day. The telescope will have been taken to pieces and it'll be interesting to see what remains. Our current instrument, WFCAM, will have been removed from above the primary to allow us to remove the mirror and it'll allow a look at the guts of one of the most productive and successful telescopes in modern astronomy.
I took a shot of WFCAM from inside the dome a couple of weeks ago and you can see it above. I'll try and take a couple of shots tomorrow so you can see the difference. I'm back up to recommission the telescope in early June so hopefully it'll look as though nothing ever happend - except the primary will look beautifully pristine!
Friday, 21 May 2010
Almost in tears
What a week. Seven days ago we said good bye to Andy Adamson who has been in charge of UKIRT for the last twelve years. This is UKIRT's loss but Gemini's gain as he's now their Associate Director of Science Operations and everyone who knows Andy will agree that he will do a wonderful job there. Gemini couldn't have chosen a better person for the role.
Last Monday I officially took over Andy's previous role at UKIRT albeit under a different title, Interim Head of Operations. The title reflects the changing situation at UKIRT and its somewhat uncertain future although things are certainly looking up after the terrible news we received on December 16 2009. That's a day I will never forget as within a period of two hours I was told UKIRT would close and Pam had cancer.
It's been a week of trying to get my head around all of the stuff Andy did, the senior management role I now have to take on and then figuring out how to change everything because during the next few months UKIRT will almost certainly be undergoing the most significant operational change in its history.
This morning our director gave a talk which outlined the changes that were coming and the consequences they would have. It was in the same room he gave that infamous talk on 16th December and I hadn't been back in the room since then. It brought back bad memories and I started to tear-up, but he gave an excellent overview of what's about to happen. I can't give details but there is some pain. This is something we will have to deal with over the next few months but the outcome is UKIRT should stay operational until early 2012 and hopefully long after then.
So, after a difficult morning, Andy emails me from Gemini to say my annual review is completed (he still has stuff to finish off here!). I look at the review and find the most kind, moving and wonderful words I have seen in a long time (other than "I love you" from Pam of course!) in his review of the appraisal interview. So the tears try to start again...
The picture at the top is one I took of UKIRT a few months ago. I was astonished to find out that Andy wanted a framed version as a going away gift. Well, he got one plus a couple of others I hope he likes including one of Gemini, his new observatory (but I couldn't afford expensive frames, sorry!).
The times they are a-changing...
Last Monday I officially took over Andy's previous role at UKIRT albeit under a different title, Interim Head of Operations. The title reflects the changing situation at UKIRT and its somewhat uncertain future although things are certainly looking up after the terrible news we received on December 16 2009. That's a day I will never forget as within a period of two hours I was told UKIRT would close and Pam had cancer.
It's been a week of trying to get my head around all of the stuff Andy did, the senior management role I now have to take on and then figuring out how to change everything because during the next few months UKIRT will almost certainly be undergoing the most significant operational change in its history.
This morning our director gave a talk which outlined the changes that were coming and the consequences they would have. It was in the same room he gave that infamous talk on 16th December and I hadn't been back in the room since then. It brought back bad memories and I started to tear-up, but he gave an excellent overview of what's about to happen. I can't give details but there is some pain. This is something we will have to deal with over the next few months but the outcome is UKIRT should stay operational until early 2012 and hopefully long after then.
So, after a difficult morning, Andy emails me from Gemini to say my annual review is completed (he still has stuff to finish off here!). I look at the review and find the most kind, moving and wonderful words I have seen in a long time (other than "I love you" from Pam of course!) in his review of the appraisal interview. So the tears try to start again...
The picture at the top is one I took of UKIRT a few months ago. I was astonished to find out that Andy wanted a framed version as a going away gift. Well, he got one plus a couple of others I hope he likes including one of Gemini, his new observatory (but I couldn't afford expensive frames, sorry!).
The times they are a-changing...
Wednesday, 19 May 2010
Californian earthshine
For those that don't know, sunlight is reflected off our planet onto the moon. Under the right conditions that light illuminates the part of the moon in shadow and it's called earthshine.
From my last day or so in California last month:
From my last day or so in California last month:
Saturday, 15 May 2010
Odd one out
Thursday, 13 May 2010
The new boss
Tomorrow is going to be a very sad day. My boss, colleague and great friend for over 20 years spends his last day in charge of UKIRT. Andy Adamson is moving to Gemini.
Andy and I have a long history together. He was my PhD supervisor back in the old days in Preston (I was his first PhD student) and he also taught some of my classes when I was an undergraduate. Not only was he a great supervisor and teacher, but towards the end of my PhD I went through a very bad time when my sister had to give up her battle with cancer and he helped me through the worst time of my life. Just recently he helped me when Pam was diagnosed with cancer and I was feeling as low and depressed as one can get - you have to remember that I got this news at the same time we were told UKIRT would be closing and I'd be out of a job. What a day that was, but Andy (and Pam) got me through it.
So Andy's off to other pastures and leaves a massive hole which I'm supposed to fill. From this weekend I'm Head of Operations for UKIRT, at least for a while until UKIRT's future is determined. I can't say I'm looking forward to it, in fact I'm scared and dreading it while also being excited about the opportunity. It's a strange mixture of emotions.
All I know is there's no way I can do the amazing job Andy did for UKIRT, but I'll do the best I can.
Andy and I have a long history together. He was my PhD supervisor back in the old days in Preston (I was his first PhD student) and he also taught some of my classes when I was an undergraduate. Not only was he a great supervisor and teacher, but towards the end of my PhD I went through a very bad time when my sister had to give up her battle with cancer and he helped me through the worst time of my life. Just recently he helped me when Pam was diagnosed with cancer and I was feeling as low and depressed as one can get - you have to remember that I got this news at the same time we were told UKIRT would be closing and I'd be out of a job. What a day that was, but Andy (and Pam) got me through it.
So Andy's off to other pastures and leaves a massive hole which I'm supposed to fill. From this weekend I'm Head of Operations for UKIRT, at least for a while until UKIRT's future is determined. I can't say I'm looking forward to it, in fact I'm scared and dreading it while also being excited about the opportunity. It's a strange mixture of emotions.
All I know is there's no way I can do the amazing job Andy did for UKIRT, but I'll do the best I can.
Wednesday, 12 May 2010
Exploring the Solar System
The NASA IRTF is often at work by the time we get to the Mauna Kea's summit. Much of its work is spent exploring the Solar System planets in conjunction with probes in orbit around various planets. Since it's an infrared telescope, similar to the one I work at, observations can be made while the sky is still bright. A bright sunlit sky usually means astronomers are still in bed but the story is different in the infrared. The main thing you need to worry about is pointing the telescope too close to the sun and accidentally focusing its light elsewhere, like the inside of the dome.
I'm sure many of you played with a magnifying glass as a kid, concentrating the sun's light into a small spot that started a fire. Multiply that power by a few thousand and you can imagine we try to avoid pointing at the sun at all costs! Despite the risks, apparently one or two observatories still have their "solar observations" singed on the inside of their domes. I won't mention any names though...
I'm sure many of you played with a magnifying glass as a kid, concentrating the sun's light into a small spot that started a fire. Multiply that power by a few thousand and you can imagine we try to avoid pointing at the sun at all costs! Despite the risks, apparently one or two observatories still have their "solar observations" singed on the inside of their domes. I won't mention any names though...
Tuesday, 11 May 2010
Another Big Island of Hawai`i photographer
Kahuku has finally made it to the Big Island of Hawai`i. She is one of my favourite photographers and I'm honored to have her comment on my own blog from time to time. I love her pictures, especially those that remind me of my younger years in the UK when punk was a big thing. There's also a sense of comedy in some of her pictures, so hope you take a bit of time to see her portfolio and her blog.
Surf
UKIRT and CFHT
Monday, 10 May 2010
Distant thunderheads?
Or atmospheric refraction? Click on the picture to take a closer look. In fact it's the latter, refraction. The photo was taken from Mauna Kea's summit a few minutes after the sun had set and shows some distant clouds still back-illuminated by the sun. Layers of air with different temperatures cause the light to refract differently which can give rise to all sorts of curious effects and shapes, especially around sunset as the earth's surface starts to cool off.
The refraction effect that caused these odd cloud shapes is the same one Pam and I saw from Moonstone Beach in Cambria, California, shown in the picture below.
The refraction effect that caused these odd cloud shapes is the same one Pam and I saw from Moonstone Beach in Cambria, California, shown in the picture below.
Sunday, 9 May 2010
Back above the clouds
It's been a little while since I spent significant time at the summit and although I've been up several times in the last month, they weren't for long runs, but I'm on one now. It's good to get back into observing again.
Things are about to change very significantly at the observatory and this includes a change of role for me which is both exciting and daunting, and I suspect I'm going to be swamped for the next few months as I figure things out. So perhaps I might cut back on my blog posts, which, you may have noticed, has already started! I'll still try and post pictures regularly but you might find me writing less.
Things are about to change very significantly at the observatory and this includes a change of role for me which is both exciting and daunting, and I suspect I'm going to be swamped for the next few months as I figure things out. So perhaps I might cut back on my blog posts, which, you may have noticed, has already started! I'll still try and post pictures regularly but you might find me writing less.
Thursday, 6 May 2010
Tuesday, 4 May 2010
Sunday, 2 May 2010
A model Santa Barbara
Well, the power's gone off again. It seems to be the local electric company's attempt to make the island feel authentically third world. My place loses power at least once a month and you get used to it over the years, but it is quite a pathetic performance by Hawaiian Electric. During the winter the power losses can often be once a week with less problems during the summer. If there's a storm or the weather is a little breezy you can can guarantee the candles will be needed. Tonight the wind is calm, there's no rain or lightning so it's more likely someone's driven into a utility pole.
At least I have my emergency backup laptop at home since my PC died, and it has a battery! Please excuse typos though. I'm a terrible typist at the best of times and this post is being written by candlelight!
Anyway, I've been meaning to try Tilt Shift Maker for a while but had no appropriate pictures before now . I was originally pointed to it by Alice at 10,000 Monkeys and a Camera and it's fun to visit. It makes your pictures look very odd and toy-like. Essentially, it keeps only a very small part of your picture in focus while defocusing the rest with the result that your image looks as if you took a photo of a model. It's quite effective and don't forget you can click on the pictures for a larger view.
At least I have my emergency backup laptop at home since my PC died, and it has a battery! Please excuse typos though. I'm a terrible typist at the best of times and this post is being written by candlelight!
Anyway, I've been meaning to try Tilt Shift Maker for a while but had no appropriate pictures before now . I was originally pointed to it by Alice at 10,000 Monkeys and a Camera and it's fun to visit. It makes your pictures look very odd and toy-like. Essentially, it keeps only a very small part of your picture in focus while defocusing the rest with the result that your image looks as if you took a photo of a model. It's quite effective and don't forget you can click on the pictures for a larger view.
Saturday, 1 May 2010
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