Thursday, 3 June 2010

A bit late for Memorial Day

I apologise for not posting this on Memorial Day earlier this week, but then again, this goes on all year round. I challenge anyone not to shed a tear while watching it.



Thank you to everyone who serves in our armed forces and to those that have fought for our freedom in the past. It also doesn't have to be a public holiday for us to remember those who died for our way of life. Please think of them at least once a day.

Lava lake from a webcam

Below are a couple of images from this evening. They were taken from the webcam placed on the edge of the crater of Pu`u O`o. From Mauna Kea's summit today the plume from Kilauea's summit was very obvious (above) yet I couldn't see any plume from Pu`u O`o which is an active crater a few miles east-south-east of Kilauea's summit. It might explain why the webcam images are so clear right now because usually all you see is the thick plume.




Live Panorama of Puʻu ʻŌʻō Cone, Kīlauea Volcano

The Kilauea summit (Halema`uma`u) has a lava lake as well, again from a webcam on the crater's edge:

Live Panorama of Halemaʻumaʻu Overlook Vent, Kīlauea Volcano

To think I live roughly twenty miles away from this activity...

Sunday, 30 May 2010

Special time

Amongst the fellow sunset watchers a few weeks ago.

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.

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!

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!

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...

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:

Moon, earthshine and Venus (and the hotel roof!).

Moon, Venus, hotel roof and trees. Again from the hotel.

From the hotel - Moon, earthshine and the Pleiades.

Saturday, 15 May 2010

Odd one out

One point for spotting the odd one out.

Two points for naming the array.

Ten points for explaining why the dishes were unusually close to each other on 10th May 2010 HST.

100 points for explaining the reason for doing this.

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.