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Galaxy Zoo
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Title: Galaxy Zoo: A correlation between coherence of galaxy spin chirality and star formation efficiency
Authors: Raul Jimenez, Anze Slosar, Licia Verde, Steven Bamford, Chris Lintott, Kevin Schawinski, Robert Nichol, Dan Andreescu, Kate Land, Phil Murray, M. Jordan Raddick, Alex Szalay, Daniel Thomas, Jan Vandenberg

We report on the finding of a correlation between galaxies' past star formation activity and the degree to which neighbouring galaxies rotation axes are aligned. This is obtained by cross-correlating star formation histories, derived with MOPED, and spin direction (chirality), as determined by the Galaxy Zoo project, for a sample of SDSS galaxies. Our findings suggest that spiral galaxies which formed the majority of their stars early (z > 2) tend to display coherent rotation over scales of ~10 Mpc/h. The correlation is weaker for galaxies with significant recent star formation. We find evidence for this alignment at more than the 5-sigma level, but no correlation with other galaxy stellar properties. This finding can be explained within the context of hierarchical tidal-torque theory if the SDSS galaxies harbouring the majority of the old stellar population where formed in the past, in the same filament and at about the same time. Galaxies with significant recent star formation instead are in the field, thus influenced by the general tidal field that will align them in random directions or had a recent merger which would promote star formation, but deviate the spin direction.

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Galaxy Zoo 2
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Galaxy Zoo 2 arrives.

We're now inviting our loyal blog and forum readers to give us a hand in testing Zoo 2, which is in beta as they say on the internet. To take part, follow this link to complete a short survey about your experiences with Galaxy Zoo so far. The whole thing shouldn't take more than 10 minutes, and you'll be rewarded with the link to our trial site for Galaxy Zoo 2.
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RE: Galaxy Zoo
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When Dr Chris Lintott, a researcher in the department of physics at the University of Oxford, first considered launching a website to ask the public to help classify photographs of 1 million galaxies, he assumed it would probably take three or four years to complete. Galaxy Zoo, launched in July 2007, was supposed to be a side project; instead it has turned into the biggest citizen-science experiment on the web.
Galaxies can be classified as spiral, elliptical or merging (when two come together). The Sloan Digital Sky Survey, or SDSS, has images of nearly a million galaxies; what those images don't have in their raw form is the information about what class of galaxy is pictured.

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Title: Galaxy Zoo : Morphologies derived from visual inspection of galaxies from the Sloan Digital Sky Survey
Authors: Chris J. Lintott, Kevin Schawinski, Anze Slosar, Kate Land, Steven Bamford, Daniel Thomas, M. Jordan Raddick, Robert C. Nichol, Alex Szalay, Dan Andreescu, Phil Murray, Jan van den Berg

In order to understand the formation and subsequent evolution of galaxies one must first distinguish between the two main morphological classes of massive systems: spirals and early-type systems. This paper introduces a project, Galaxy Zoo, which provides visual morphological classifications for nearly one million galaxies, extracted from the Sloan Digital Sky Survey (SDSS). This achievement was made possible by inviting the general public to visually inspect and classify these galaxies via the internet. The project has obtained more than 40,000,000 individual classifications made by ~100,000 participants. We discuss the motivation and strategy for this project, and detail how the classifications were performed and processed. We find that Galaxy Zoo results are consistent with those for subsets of SDSS galaxies classified by professional astronomers, thus demonstrating that our data provides a robust morphological catalogue. Obtaining morphologies by direct visual inspection avoids introducing biases associated with proxies for morphology such as colour, concentration or structural parameters. In addition, this catalogue can be used to directly compare SDSS morphologies with older data sets. The colour--magnitude diagrams for each morphological class are shown, and we illustrate how these distributions differ from those inferred using colour alone as a proxy for morphology.

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Title: Galaxy Zoo: The large-scale spin statistics of spiral galaxies in the Sloan Digital Sky Survey
Authors: Kate Land, Anze Slosar, Chris Lintott, Dan Andreescu, Steven Bamford, Phil Murray, Robert Nichol, M.Jordan Raddick, Kevin Schawinski, Alex Szalay, Daniel Thomas, Jan Van den Berg

We re-examine the evidence for a violation of large-scale statistical isotropy in the distribution of projected spin vectors of spiral galaxies. We have a sample of ~ 37,000 spiral galaxies from the Sloan Digital Sky Survey, with their line of sight spin direction confidently classified by members of the public through the online project Galaxy Zoo. After establishing and correcting for a certain level of bias in our handedness results we find the winding sense of the galaxies to be consistent with statistical isotropy. In particular we find no significant dipole signal, and thus no evidence for overall preferred handedness of the Universe. We compare this result to those of other authors and conclude that these may also be affected and explained by a bias effect.

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By posting on an Internet forum, Bill Keel set off a research project that will help astronomers learn more about the formation of galaxies and, perhaps, the universe.
Best of all, volunteers in a Web project to classify more than 1 million galaxies performed the research. All the University of Alabama professor had to do was ask the amateur astronomers to send a special sort of image his way.
The armchair astronomers helped Keel find more than 500 images of overlapping galaxies, which happen when a galaxy appears behind another from earths view of the universe. The foreground galaxy is backlit by the formation behind it, making a silhouette of cosmic dust.

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You're sitting on a pile of about a million telescopic photos of the universe, and each one needs to be classified. Bit of a job. So what do you do? Astronomers at the University of Portsmouth, Oxford University, and Johns Hopkins University came up with a solution last week that not only alleviated the burden but also generated an enthusiastic response from the public: They opened up the project to volunteers via the Internet.

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A new project known as Galaxy Zoo is calling on members of the public to log on to its website and help classify one million galaxies.
The hope is that about 30,000 people might take part in a project that could help reveal whether our existing models of the Universe are correct.
Computers users undergo a three-minute online tutorial and are then allocated a series of images and asked to decide whether each one shows a spiral or an elliptical galaxy.

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"Non-professionals have always been deeply involved in studying the sky and they now have yet another opportunity to make themselves really useful. Moreover, their help is now of immense value so do join up as I am doing myself" - Sir Patrick Moore.

www.galaxyzoo.org

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