"The strongest affection and utmost zeal should, I think, promote the studies concerned with the most beautiful objects. This is the discipline that deals with the universe's divine revolutions, the stars' motions, sizes, distances, risings and settings . . . for what is more beautiful than heaven?" - Nicolas Copernicus
The relaunch of Galaxy Zoo doesn't only include the fantastic new images from the CANDELS survey on Hubble Space Telescope, but also includes over 200,000 new local galaxies from the Sloan Digital Sky Survey. We've had a lot of questions about where these galaxies came from and why they weren't put into earlier versions of Galaxy Zoo, so I thought I'd write a bit about these new images.
The Sloan Digital Sky Survey Project (SDSS) is currently in its 3rd phase (SDSS-III). You can read all about the history of SDSS here, and here, but briefly SDSS-I (2000-2005) and SDSS-II (2005-2008) took images of about a quarter of the sky (which we often refer to as the SDSS Legacy Imaging), and then measured redshifts for almost 1 million galaxies (the "Main Galaxy Sample", which was the basis of the original Galaxy Zoo and Galaxy Zoo 2 samples; plus the "Luminous Red Galaxy" sample) as well as 120,000 much more distant quasars (very distant galaxies visible only as point source thanks to their actively accreting black holes).
Following the success of this project, the Sloan Digital Sky Survey decided they wanted to do more surveys, and put together a proposal which had four components (BOSS, SEGUE2, MARVELS and APOGEE - see here). To meet the science goals of these projects they realised they would need more sky area to be imaged. This proposal was funded as SDSS-III and started in 2008 (planned to run until 2014).
The first thing this new phase of SDSS did was to take the new imaging. This was done using exactly the same telescope and camera (and methods) as the original SDSS imaging. They imaged an area of sky called the "Southern Galactic cap". This is part of the sky which is visible from the Northern Hemisphere, but which is out the Southern side of our Galaxy's disc. It totals about 40% of the size of the original SDSS area, brining the total imaging area up to about 1/3rd of the whole sky. The images in it were publicly released in January 2011 as part of the SDSS Data Release 8 (DR8 - so we sometimes call it the DR8 imaging area).
This illustration shows the wealth of information on scales both small and large available in the SDSS-III's new image. The picture in the top left shows the SDSS-III view of a small part of the sky, centered on the galaxy Messier 33 (M33). The middle and right top pictures are further zoom-ins on M33.The figure at the bottom is a map of the whole sky derived from the SDSS-III image. Visible in the map are the clusters and walls of galaxies that are the largest structures in the entire universe. Figure credit: M. Blanton and the SDSS-III collaboration
We have selected galaxies from this area which meet the criteria for being included in the original Galaxy Zoo 2 sample (for the experts - the brightest quarter of those which met Main Galaxy Sample criteria). Unfortunately in this part of the sky there is not systematic redshift survey of the local galaxies, so we will have to rely on other redshift surveys (the most complete being the 2MASS Redshift Survey) to get redshifts for as many of these galaxies as we can. We still think we'll get a lot more galaxies and, be able to make large samples of really rare types of objects (like the red spiral or blue ellipticals). Another of our main science justifications for asking you to provide us with these morphologies was the potential for serendipitous discovery. Who knows what you might find in this part of the sky. The Violin Clef Galaxy is in the DR8 imaging area and featured heavily in our science team discussions of if this was a good idea or not.
And interesting things are already being found in just a week of clicks. The new Talk interface is a great additional place for us to discuss the interesting things that can be found in the sky.
For example this great system with tidal tails and a Voorwerpjie:
There are also rather more artifacts and odd stuff going on in these new images than I think we saw in the SDSS Legacy sample (from GZ1 and GZ2). Remember these are completely new images you are looking at. It really is true that no-one has looked at these in this level of detail (or perhaps ever) before. The original sample had a sanity check at some level, since when GZ1 ran the majority of the sample had already been targeted by SDSS for redshifts (so someone had to plug a fibre into a plate for each galaxy). In this new imaging all that has happened is that a computer algorithm was run to detect likely galaxies and set the scale of the image you see. Sometimes that mistakes stars, satellite trails, or parts of galaxies for galaxies. Always classify the central object in the image, and help us clean up this sample by using the star/artifact button.
And you can enjoy these odd images too. I like this collection of "GZ Pure Art" based on just odd things/artifacts classifier "echo-lily-mai" thought were pretty. :) If you get confused by anything please join us on Talk, or the Forum where someone will help you identify what it is you're seeing.
Here are some of the photos I took of stuff (related to astronomy!) at the IAU in China.
Here's the giant IAU 2012 sign outside the convention centre. Plus some SKA balloons (and someone's children!). ;) It was a busy meeting with the children accompanying us (my husband is also an astronomer) and attending an UNAWE run workshop during the first week (article about the workshop is online here) and also in the 8th Edition of the IAU Daily Newspaper.
Since my daughter was "quoted" here's the article.
I enjoyed the Daily Newspaper, I admit partly because my talk (and me) were featured on the front page of the first one:
But also because I had been given the task to collect a newspaper for every day to share with someone special who has a collection of all such newspapers from every IAU GA since the meetings began. The 2012 addition to the collection I admit is still sitting on my desk, but will get sent off very soon.
This was the Newspaper stand where you could collect the print editions:
So I gave this big talk on the evening of the first day. Here's me by the sign which advertised the talk (which didn't come out).
The (almost) empty hall before people started coming in. This is apparently the location of the 2008 Olympic Badminton Events. It seats 3000 - but a long stretch the largest room I've ever spoken in (as people seemed to want to point out to me often in the run up to my talk!).
Here's my lovely title slide (with credit to Zooniverse designed David Miller) displayed on the big screen.
Bryan Gaensler (@SciBry) snapped (and tweeted) this shot of me talking to Brian Schmidt (@cosmicpinot) before the talk. Brian gave one of the other Invited Discourses.
Finally, with credit to my husband Wynn Ho (for taking the video - and he apologise for the poor camera work which was related to him also watching the children at the same time), here's a short video of the introduction to the talk (given my my former thesis advisor Prof. Martha Haynes) and my
Chinese welcome words.
The day after my talk, the hall was rather more full for the Opening Ceremony of the IAU meeting, at which Chinese Vice President Xi Jinping (a potential sucessor to Hu Jintao) addressed us. The full text of his speech can be read in the 3rd Daily Edition of the IAU Newspaper.
Following this speech, the award of the 2012 Gruber Prize and Fellowship, and a lovely public lecutre by Jocelyn Bell, was a display of Chinese culture (various dances, acrobatics, music etc). At the end of this the staff and students of the Chinese National Astronomy Observatory treated us to a dance display with an astronmical theme.
Here are some pictures I took of this, which was a bit cutesy, but I enjoyed!
I particularly enjoyed the silver umbrellas making a variety of radio telescope shapes.
And the finale.
The exhibition area at an IAU meeting is always fun, and I particularly enjoyed several of the models on display. Oddly given my interest in the project I didn't take a picture of the lovely LOFAR LBA models, but I was happy to finally see them in person.
The ALMA booth had some great lego models. This one of the transporter which moves the dishes.
And this model of an ALMA dish.
This was a nice model of the Giant Magellan Telescope I think.
The Korean Astronomy booth had the best takeaway models. You (well I) can build the below from a flat packed kit. My kids made during the day camp the moveable models of Magellan (which we also had fun destroying to pack to bring back to the UK). These were really impressive.
I also liked this model (and the setting of it) of a Cerenkov Array Telescope. These are designed to detect light flashes from Cerenkov radiation when gamma rays enter our upper atmosphere.
In one corner of the main lobby was a collection of what looked like bad astronomy art. On closer inspection though you could discover, that these were actually silk embroidered versions of astronomical images - a craft typical of the Suzhou area (near Shanghai) which I had visited on a previous trip to China.
Here some of the artists are at work embroidering the Earth, and a map of the cosmic web. These were really impressive.
I enjoyed the displays (and a lunchtime lecture) on Chinese Ancient Astronomy. The below panel is a list of predictions of solar eclipses. The Chinese in around the 10th century made astronomical observations and records comparable to those westeners used in the 16th/17th century to develop our models of gravity. The lunchtime lecture included an interesting discussion on the lack of a Chinese version of Kepler.
There was also the below, full working replica (on a slightly smaller scale than the original) of an ancient Chinese water clock. This was the first clock in the world able to keep accurate time. And it was also beautifully carved.
Finally, the whole event had reminders of the previous use of the building. As is typical for most large conferences (AAS excepted) the poster sessions were in an out of the way corner of the event. I managed a visit while trying to walk my son to sleep one afternoon, and snapped the below shot of the floor of the room.
I was interviewed for "Amateur Astronomer" (a Chinese astronomy magazine). Here's the first page of the article they sent me.
And a photo they took of me right after giving my talk when they gave me the previous edition of the magazine.
I also talked with someone from Southern Weekly (a Chinese newspaper with a readership of 8 million), who published this article (in Chinese).
And I talked with people from China Radio International, who said they planned to run the story, but I'm not sure what came of that yet. They recorded me saying "Xin Xi Zong Dong Yuan" (our Chinese translation of "Galaxy Zoo"), and explaining (in English) what Galaxy Zoo is.
