Galaxy Zoo

Galaxy Zoo is a citizen science, online astronomy project which invites members to personally classify millions of galaxies by hand. The project was inspired by Stardust @ home, in which the public was asked by NASA to search images from a mission to a comet. Galaxy Zoo was a collaboration between the universities of Oxford and Portsmouth, and the Johns Hopkins University in Baltimore and Fingerprint Digital Media, Belfast.

Target

Galaxy Zoo members should divide galaxies into several categories: elliptical or spiral. In the case of a spiral galaxy can be made between the rotation clockwise and counterclockwise. Astronomical knowledge was not necessary for classification. In the tutorial, the volunteers were explained the differences between the types of galaxies, and they could try to sample images. They could later verify the correctness of their classification. It happened that images of meteorites tails appear as contrasting colored lines in the picture or to see pictures of a single, large, colored star were.

The images of galaxies, were automatically taken from the Sloan Digital Sky Survey using a digital camera, which was mounted on a telescope. This telescope is located at the Apache Point Observatory in New Mexico, USA.

It was hoped that the public classification provides valuable information about the distribution of different types of galaxies. This would provide researchers the opportunity to review current models of galaxies and expand.

Theorists believe that spiral galaxies can combine to form elliptical galaxies. Similarly, elliptical galaxies to spiral galaxies, if they get added more gas or stars. In addition, the rotation of spiral galaxies is, according to Professor Michael Longo of the University of Michigan is not random, as one might think at first. This assumption is based on an analysis of 1660 galaxies and is therefore not proven. These more galaxies would be needed.

Importance of volunteers

It turned out that computer programs were not reliably able to classify galaxies automatically. According to the Galaxy Zoo team member Kevin Schawinski the human brain is much more powerful than a computer program " in this field of pattern recognition. " Without human volunteers, the researchers would have required years to edit the photographs. It is estimated that approximately 10,000 to 20,000 volunteers, the process can be shortened to about 1 month.

Previously unseen images

Chris Lintott, another Galaxy Zoo member, commented: " One advantage is that you see pictures of areas of the universe that has never seen someone previously These images were automatically recorded and processed, so the first galaxy you. sees when one logs in, one that no one else has ever seen. " This was confirmed by Schawinski.

Progress

A Galaxy Zoo Newsletter dated 2 August 2007 was found that 80,000 volunteers had more than 10 million images classified, exceeding the goal of the first phase of the project far.

Another goal was to "keep classify each galaxy of at least 20 different users ." Important a multiple classification was because it made it possible to create a reliable database that met the high standards of the scientific community. For the first time it was thus able not only to distinguish spiral galaxies of the ellipse, but also spiral galaxies of fainter and less sharp things.

The final data sets included 34,617,406 clicks of a total of 82 931 users (now loudly blog 368 269, January 2011) came from.

A surprising result was that more than half of the galaxies were classified as rotating counterclockwise. Because of the random orientation of galaxies in space, the rotation directions should be the same but often. Then, by providing a psychological cause images were presented in black and white or mirrored be excluded for a preferred classification of the direction of rotation. But it turned out that just that was the cause.

Galaxy Zoo operates a forum where users can post their most striking images.

Unofficial results and conjectures

Ring galaxies appear significantly more likely to occur than previously thought. Only two previously known galaxies were classified as " three-legged ", ie, with three spiral arms. At Galaxy Zoo significantly more were found. Also pictures of uniting or otherwise interacting galaxies have been classified.

The most spectacular single object, which has been discovered in the context of Galaxy Zoo, a blue-green object, Hanny 's Voorwerp ( " Hanny's Object" ) is called, the nature of which could be decrypted only after further research with the Hubble Space Telescope. The glow of Hanny's Voorwerp can be explained by earlier active phases of the neighboring galaxy.

In addition, a " scientific blog", an official summary of the recent Galaxy Zoo results exist.

Galaxy Zoo 2

After Galaxy Zoo has been completed, started after an extended beta test on 17 February 2009 "Galaxy Zoo 2 ".

Galaxy Zoo 2 goes a step further in the classification. 250,000 of the brightest galaxies are included in this project, which (lights almost not to excessively bar or not, center ) are classified and other features on the shape, number of spiral arms, appearance of the center. There is also a way to mark " oddities " in the image. In addition, this project contains less poor quality photos.

After also Galaxy Zoo 2 was completed, launched Galaxy Zoo Hubble, with images from the Hubble Space Telescope. From this point on other projects over the Zooniverse family were always published.

Zooniverse

Zooniverse is a citizen science portal, which was created from the original Galaxy Zoo project. It includes several projects that allow users to engage independently in scientific projects such as astronomy or climatology. Unlike other Internet - based scientific projects, such as SETI @ home, which uses the free computer processing power to analyze data, the Zooniverse project uses the active participation of real people to complete research. On January 1, 2012 there was a community of 503 417 volunteers.

Projects

Active projects are currently: