Archive for April 2008
What we’ve actually been doing
As our last night on the mountain draws to an end, we’re fighting strong winds and occasional technical glitches in the camera control system (solution : turn off, turn back on again) to get images of some of the most useful galaxies we’ve seen yet. One is a more distant version of Bill’s personal touchstone, NGC 3314. I hope you’ve enjoyed the blogs we’ve posted over the last five nights - there will be more to come as the work on all of this fabulous data continues However, you’d be forgiven if you failed to work out from the posts what it is that has been keeping us, or rather Anna in particular, so busy. Read more
2 comments
Dust gets everywhere
The whole point of the observing run is to try and understand dust in external galaxies, but we’ve already encountered dust in the Milky Way, and producing spectacular sunsets and tonight I observed another manifestation of dust - the zodiacal light, subject of Brian May’s thesis.
You can see it in this picture from the all sky camera, as the glow over on the right.
The glow is from light reflected off dust in the plane of the solar system, the left overs from the process that produced the planets. This was a particularly good display, reaching almost up to the zenith. It’s the best display I’ve ever seen, having dashed out into the wind. The wind is the major feature of tonight’s observing so far, being strong enough to force us to point the telescope away from it, and loud enough to cause the dome to creak and moan. All a little disturbing, but apart from that conditions seem good.
No commentsSecond paper now available online
The second Galaxy Zoo paper, which introduces the survey and provides details of our initial data analysis, is now available online via astro-ph.
I look forward to hearing your comments….
9 commentsCaption competition results
I’m proud to announce the winners of the first Galaxy Zoo Caption competition. Bill, Anna and I decided the winner by printing out all the entries and then standing around pointing at them. All the entries were appreciated in getting us through the wee small hours of the mornings, but there can only be, in this case, two winners: pluk (”Bill: “No Chris, it’s not your turn yet, Anna had a match”) and Curtis (”After the witnesses identified the suspects from the photo lineup, they were quickly arrested.”).If both would contact me via the forum or email (chrislintott AT cantab.net) then we’ll get your prizes to you.
No commentsShades of opinion
Colour in astronomy is a difficult and often controversial topic. Rather than just lump all the photons together, we like to use separate filters which allow a standard set of wavelengths through; that means that when I talk about a ‘blue’ image, then I will certainly be talking about the same ‘blue’ as anyone else. Each colour encodes information; blue represents young stars, red old stars or emission from dust. This is all very well, but the problems start when we try to produce colour images. Which filters do we use? No camera has the same response as the human eye, so this can be a controversial question. The Galaxy Zoo images are based on three of the Sloan filters - blue is blue, but red is green and infrared is red. That’s why the Voorwerp appeared as a blue blob even though it’s really green.
6 comments