Help astronomers study galactic evolution with Galaxy Explorer

A new citizen science project lets anyone help astronomers explore distant galaxies. Source: Galaxy Explorer

I’ve written before about the ways anyone with an Internet connection can help study the most fundamental questions in the Universe thanks to the power of crowdsourced citizen science. Now Australian astronomers have launched the Galaxy Explorer project so citizen scientists can help study the evolution of galaxies. 

Could this be two galaxies colliding 2.8 billion years ago? I thought so, but even if I'm wrong classifications by other citizen scientists will produce the right answer. Source: Galaxy Explorer

The Galaxy Explorer website shows a picture of a galaxy and asks volunteers a series of questions that classifies the galaxy’s shape. Does it have spiral arms, for example, or is it cigar-shaped? Galaxy Explorer adds an extra step by asking its volunteers to help measure the amount of light the galaxy emits. A simple click and drag lets volunteers center a ring around the galaxy. 

Anyone who has contributed to the Galaxy Zoo family of crowdsourced astronomy projects will recognize the classification process. The interface is a little different, but both projects accomplish the same thing: classifying hundreds of thousands of galaxies through the combination of human perception and the wisdom of the crowd. 

Computer algorithms can analyze millions of images quickly, but only if the objects are distinct and predictable. Human perception evolved to recognize even the most indistinct objects (think tigers in the jungle). One person’s judgement call may not be all that accurate, but averaging judgement calls from several people gets results as good as an expert analyst. Galaxy Zoo was one of the earliest, and biggest, projects to crowdsource human perception to produce real science. 

Galaxy Explorer follows in Galaxy Zoo’s footsteps, but it’s no copycat. Where Galaxy Zoo studied the population of galaxies at certain epochs in the Universe’s history, Galaxy Explorer studies the evolution of galaxies across 3 billion years. Keep in mind that when talking about galaxies time and distance are two sides of the same coin. Light from the most distant galaxy in the Galaxy Explorer library began its journey 4 billion years ago when the galaxy was a little more than 10 billion years old. Light from the closest galaxy began its journey 800 million years ago, making the closest galaxy more than 3 billion years older than the farthest galaxy! 

The Galaxy Explorer scientists want to study how galaxies - and the forces that shaped them - changed over those 3 billion years.

Galaxy Explorer also differs from Galaxy Zoo in its use of incentives. The project will award two telescopes to individual Australians and two iPads to Australian schools who make at least ten classifications. Will the prizes matter? More than 1.4 million people around the world have participated in Galaxy Zoo and other Zooniverse citizen science projects just for the chance to make a difference.

Personally, I think people contribute to citizen science projects for the chance to do science that matters. Some lucky Australians will win prizes - and good-on-em for that. The Australian government funds Galaxy Explorer so why shouldn't they get prizes? Ultimately, the 200,000 galaxy catalog that citizen scientists create for Galaxy Explorer’s astronomers may help answer questions like: When and how did the rate of galactic collisions and mergers change? How does the distribution of galaxy types change over time? How do spiral arms and bars form? 

That’s what amateur space exploration is all about!