* Astronomy

First citizen science platform celebrates 100 project milestone

Almost 10 years to the day since it started, The Zooniverse, the world's largest and most popular people-powered research platform will launch its 100th project; Galaxy Nurseries. The online platform runs on support from volunteers, of which there are now hundreds of thousands worldwide. These volunteers act as armchair scientists, helping the team with their online research from the comfort of their own homes.
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Title: Galaxy Zoo: Motivations of Citizen Scientists
Authors: M. Jordan Raddick, Georgia Bracey, Pamela L. Gay, Chris J. Lintott, Carie Cardamone, Phil Murray, Kevin Schawinski, Alexander S. Szalay, Jan Vandenberg

Citizen science, in which volunteers work with professional scientists to conduct research, is expanding due to large online datasets. To plan projects, it is important to understand volunteers' motivations for participating. This paper analyses results from an online survey of nearly 11,000 volunteers in Galaxy Zoo, an astronomy citizen science project. Results show that volunteers' primary motivation is a desire to contribute to scientific research. We encourage other citizen science projects to study the motivations of their volunteers, to see whether and how these results may be generalised to inform the field of citizen science.

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Title: Galaxy Zoo: Quantifying Morphological Indicators of Galaxy Interaction
Authors: Kevin R. V. Casteels, Steven P. Bamford, Ramin A. Skibba, Karen L. Masters, Chris J. Lintott, William C. Keel, Kevin Schawinski, Robert C. Nichol, Arfon M. Smith

We use Galaxy Zoo 2 visual classifications to study the morphological signatures of interaction between similar-mass galaxy pairs in the Sloan Digital Sky Survey. We find that many observable features correlate with projected pair separation; not only obvious indicators of merging, disturbance and tidal tails, but also more regular features, such as spiral arms and bars. These trends are robustly quantified, using a control sample to account for observational biases, producing measurements of the strength and separation scale of various morphological responses to pair interaction. For example, we find that the presence of spiral features is enhanced at scales < 70 h^-1 kpc, probably due to both increased star formation and the formation of tidal tails. On the other hand, the likelihood of identifying a bar decreases significantly in pairs with separations < 30 h^-1 kpc, suggesting that bars are suppressed by close interactions between galaxies of similar mass. We go on to show how morphological indicators of physical interactions provide a way of significantly refining standard estimates for the frequency of close pair interactions, based on velocity offset and projected separation. The presence of loosely wound spiral arms is found to be a particularly reliable signal of an interaction, for projected pair separations up to \sim 100 h^-1 kpc. We use this indicator to demonstrate our method, constraining the fraction of low-redshift galaxies in truly interacting pairs, with M_{\ast} > 10^9.5 M_\odot and mass ratio < 4, to be between 0.4 - 2.7 per cent.

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Live Chat - Hangout with Us

Tomorrow afternoon we'll be holding a live chat with Galaxy Zoo science team stars Chris Lintott and Karen Masters. Starting at 2pm British Summer Time (1300 UT, 9am EST, 3pm CEST), Chris and Karen will be answering your questions and talking about some of the recent Galaxy Zoo work, made possible why your efforts on galaxyzoo.org.
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