Overlapping galaxies in color and in detail
We’re making progress in working on the Kitt Peak images of overlapping galaxies (encouraged by recently learning that we have 3 more nights this November, so keep those candidates coming in!). Now that various meetings and proposal deadlines are over, there’s some time to show off color composite images and point out some of the things we’re looking at. For most of these galaxies, we took images in two filters – the B band (blue), which lies between the SDSS u and g filters, and the I filter, which used to stand for infrared but nowadays (with the proliferation of genuine infrared imagers at much longer wavelengths) we think of as a red just a bit too deep for our eyes to see. Making a color image takes three filters, not just two. Fortunately, the colors of most galaxies are so well-behaved that we can synthesize the middle filter (green) from the two we have; this is something done pretty often with Hubble images as well. I then pasted the three colors together using a brightness mapping that is logarithmic starting slightly below the sky-brightness level and consistent across the various galaxies – this ends up much like the familiar SDSS color display. But enough of the details – let’s get to the galaxies.
Classifying Ring Galaxies
My name is Ciaran O’Hare, I’m a sixth form student at The Cherwell School in Oxford and I came to the Oxford University Astrophysics department as part of my work experience for Year 12. I was set a task to complete of the course of the week, to sort through hundreds of e-mails from from the users of Galaxy Zoo about the unusual ring galaxies.
Galaxy Zoo Meet-up on Tuesday
Just a reminder (in the absence of the forum) that there’s a Galaxy Zoo meet-up in London this Tuesday. It’ll follow a lecture I’m giving as part of the Royal Astronomical Society’s Lunchtime Lecture Series at their apartments in Burlington House, Picadilly (look for the Royal Academy of Arts). The lecture begins at 1, although you might want to turn up a bit earlier to make sure you get a seat, and we’ll gather in the courtyard outside the RAS at 2 and then go and find somewhere for a late lunch. Hope to see you all tomorrow. Chris
10 JUNE: RAS LUNCHTIME LECTURE: HUBBLE, BUBBLE, TOIL AND TROUBLE: A BRIEF HISTORY OF THE MOST FAMOUS TELESCOPE EVER MADE: BURLINGTON HOUSE, LONDON
Dr Chris Lintott, postdoctoral researcher at the University of Oxford, STFC Science and Society Fellow and co-presenter of the BBC ‘Sky at Night’ will tell the story of the NASA / ESA Hubble Space Telescope (HST), in orbit since 1990. This autumn, astronauts aboard the space shuttle Atlantis will carry out one of the most difficult repairs in history, with the aim of restoring the HST to full working order. Dr Lintott’s lecture will tell the HST story, and look forward to the discoveries still to be made.
The lunchtime lectures are open to everyone and take place in the newly-refurbished Burlington House, the headquarters of the RAS off Piccadilly in central London. The lectures take place at 1pm on the first Tuesday of each month from September to June and the audience can take their seats from 12.45.
The biggest astronomical collaboration in history… just how big?
Chris and I are at the AAS meeting in St. Louis. Chris has been keeping up with the meeting on his blog, and we’ve both given talks about Galaxy Zoo. Everyone here is really excited about what we’ve been able to do with Galaxy Zoo – great job, everyone!
Galaxy Zoo Forum downtime
If you’re a regular user of the forum at http://www.galaxyzooforum.org/ you’ll notice that it’s currently offline. There’s been a sizeable server outage which has affected it (along with many other websites), and we hope it will be back up soon – but this outage is out of our control. We were actually already planning to transfer it to a new server anyway, and we were hoping to do this on Tuesday, although this downtime may unfortunately get in the way of our plans. If the forum does come back up in time, we may take it down for Tuesday in order to make this transfer, but it should be back up shortly after that. Please bear with us until we can get everything back up and running properly, we’re running around in our t-shirts and underpants to get this going!
Update: Forum is still down unfortunately, but the support staff at the hosting site are working hard to bring it back up. It looks like the transfer will be delayed – and hopefully we’ll be able to give some warning of any resulting downtime from that.
Update 2: (Wednesday morning) Unfortunately there’s been hardware issues as the support technicians tried to bring the server back up. They’re still working on bringing it back up – no estimate for when this will take place I’m afraid.
Update 3: (Thursday morning) We’re in the process of trying to reinstall the forum framework and content back on the original server. A temporary forum is in place. It is not organised in the same way and has a different theme to emphasise this fact, and no posts there will be retained (except maybe in rare cases).
Update 4: (Wednesday morning – 11th June) The disk holding the forum is with a data recovery team, but unfortunately they won’t be able to get anything off for approximately another week at the earliest.
What's an Astronomer's favourite Birthday Gift?
As you can see, we woke up this morning, to find that the Space Telescope Science Institute — the organisation running the world’s most famous telescope, Hubble — have sent out their approval and denial letters for the next cycle of observations with the Telescope. Our proposal for observing the Voorwerp (led by Principal Investigator Bill Keel) was approved for 7 orbits. Getting time on HST is hard at the best of times, and this time round was particularly difficult. Hubble is currently waiting for a visit from astronauts to carry out a desperately needed set of repairs and upgrades, and every astronomer in the world wanted to be first in the queue once it’s back on top form. To give you an idea, more than 20,000 orbits were requested when there were only 3,500 of them to go round – and 7 of them now belong to Galaxy Zoo.
So when will you see a gorgeous Hubble image of the Voorwerp? Not for a while yet. First, the Space Shuttle has to successfully complete its final service mission to repair the Hubble and install new instruments. This is currently scheduled for October 8, 2008. After all the repairs are done and the spacecraft has been checked out thoroughly, we then have to wait for the Voorwerp to actually be visible on the sky for Hubble. All this will take at least several months more. And of course once the data is taken, we then have to reduce it first to produce a picture. Still, it will be a wonderful opportunity for us to learn more about what the Voorwerp is.
By coincidence, today’s the birthday of the Voorwerp’s discover. Happy birthday, Hanny – and enjoy your present from the Space Telescope Science Institute.
A Big Thanks to all our Collaborators!
Late last year we hinted at a surprise present for you. We also asked you for your name if you didn’t mind it being published…
Well, here you are:
No journal would allow us to have an author list with more than 100.000 names on it. However, you are our collaborators and we wanted to acknowledge your contributions that made Galaxy Zoo possible. If you look at the first page of Kate’s accepted paper, you will see that we link to this page:
All papers that the Team are working on will have this link on them to acknowledge you. In the future, when we make the Galaxy Zoo data available publicly for other astronomers to use, we’ll also ask them to do the same when they publish their results.
So once again, a Big Thanks from the Team. You can download a full-resolution JPEG or PDF version of the poster at http://www.galaxyzoo.org/Volunteers.aspx.
First paper accepted
We have just found out that the first Galaxy Zoo paper we submitted has been accepted for publication in the Monthly Notices of the Royal Astronomical Society. This is really exciting, and what is even better is that we were not required to make any revisions or corrections first! This is almost unheard of – so unheard of that it’s not listed as a possibility in Kevin’s outline of the peer review process in a previous post. We expected the anonymous referee to produce a report that commented, criticised, and quibbled about parts of the paper that they were not satisfied with. But we in fact received no report and it went straight to being accepted. Which means that the referee must have been very happy with what we had done. Hoorah!
It will hopefully be appearing in the online version of MNRAS in a month, then a little longer for printed versions. But there is no need to have a subscription to MNRAS to view the paper as the paper is also available publicly here (and we will be sure to keep the versions the same).
We will now be writing a less technical version of the paper for those interested – the idea is to make the results accessible to all the Galaxy Users. So this paper will have the same figures, data, etc. but with more clarification where necessary, less astro-jargon, and some extra reflection on the results. Watch this space!
Third Galaxy Zoo paper submitted
Update : Paper now available.
It has taken over six months and a lot of work, but we have finally decided the third Galaxy Zoo paper is ready for submission to a scientific journal, and to be made public. The paper was already in reasonably good shape a month or so ago, but given the number of interesting results it contains, we wanted to be sure the presentation is as clear as we can make it. We therefore had yet another round of internal review by the coauthors, and elicited comments from a couple of other colleagues with links to the project. The response was very helpful and encouraging, so I decided to take a bit more time to improve the analysis further and perform some extra tests. We’ve now got a paper we are all really pleased with. We hope that all of you, and the journal referee, agree with us!
The paper is long, 30 pages in total. Even so, we’ve tried to make the paper as readable as possible by shifting some of the material to appendices (additional sections at the end of the paper). Much of the length of the paper is due to the large number of figures. Again though, we’ve tried to make these easier to absorb by combined multiple plots into single figures and maintaining a consistent style.
The paper has been submitted to the Monthly Notices of the Royal Astronomical Society (MNRAS), one of the world’s principal astronomy journals, and the same publication that the two previous Galaxy Zoo papers (by Kate and Chris) have been submitted to. The paper will now go for peer review. Hopefully we will have the referee’s comments back in a month or so, then there will probably be a few changes to make before it is accepted by the journal and published. As this process takes so long, and this work is so timely, we have decided to make the paper public before it is accepted by MNRAS, so other researchers can see our work as soon as possible. The paper has therefore been added to the astro-ph archive. It will be available for anyone to read from Tuesday 3rd June.
I’m taking a break for a fortnight, but then I’ll write a few blog posts, following on from this one, explaining all the results of the paper in less technical terms.
Update : Paper now available.
Merger hunting one month on
I (Waveney) joined Galaxy Zoo a few months ago and was a relatively quiet soul, who didn’t do very much…
A month ago I was sitting at a computer, and in theory looking at job ads, when I saw Chris’s request – Merger Hunters Needed. I read what was wanted and thought it would be fun to do, but the method requested was awful. One of my part time businesses is running a small scale internet services company and I like writing code to do fancy things. So I offered to provide a web page to do the merger hunting. I was busy during the day, but in about 4 hours in the evening I got the first program working, put it on one of my websites on my server and let the world know via the forum and the blog. I became famous overnight. The next day, Chris wanted to raise awareness and offered to add it to the Zoo front page and send out the newsletter, I requested that the front page be changed, but that the newsletter should wait a couple of days (just in case).
The following day, I was getting a lot of favorable comments and Chris mentioned it in the Blog, and Alice put it on OOTD. A couple of people commented about performance – this initially perplexed me as the program had almost no impact on the server. Then I found a limitation in the SDSS server about repeated requests from the same address, and I realised that this was the cause of the problem. I re-wrote fetches of the data and wrote my first ever SQL to pre-fetch the necessary info from the server. No sign of the front page change.
Usage grew, comments came and I started adding features, those useful features that I wanted like Zoom, Back and direct searches of the forum, requests for Invert, and then grid lines, and and and. I also leant a lot more SQL. Chris requested I have a “Basic” display and an “Advanced” display – done within the hour – still no sign of the front page or newsletter.
Prompted by the speed that one Merger Checker was working, and following discussions with Chris, the system was extended with a lot more data for images with lower merger ratings from the original Zoo. This required a complete re-write of the underlying data management – it took a few hours. Usage grew – still no sign of the front page or newsletter.
I was seen at the Winchester gathering, had it been a month before I would have largely been an unknown – now I was infamous. Usage grew – still no sign of the front page or newsletter.
Usage was steady, but at current rate it was going to take several months to get useful answers, I wrote to Alice requesting it be on OOTD again as it would be months before Chris had the front page changed – what happened – the front page changed almost as I finished sending the message. Users grew, but the rate of image classifications, didn’t change much. Oh well we will have to wait and see. Still no sign of the newsletter.
On Wednesday just after 7pm I noticed a sudden jump in users – 1 or 2 was not usual, but 5 in an hour was unheard of, clicked the status again and it had gone up 5 more! I asked on the forum and somebody said the newsletter was out! The next couple of hours where frenetic as the Merger hunters climbed from 200 to 700, and 20,000 images were seen. I kept an eye on the server – it has handled that sort of load before, and it did this time the only casualty was a logging program that runs in the middle of the night, when the system is usually quiet…
As I write this what started as a quick 4 hours a month ago has become the leading use of my talents for the last few weeks. 1200 users have seen 200,000 images and all sorts of useful results are beginning to be found. Oh and I am still looking for work – anybody want an experienced system/network designer and/or real time programmer?
Galaxy Zoo 
