Astronomers Are Doing Real Science With Space Photos They Found on Flickr

For an astronomer exploring the depths of the universe, peering into space can cost a lot of money and time. Getting images detailed enough to see the minutiae of galaxies and nebula can take a long time with a very expensive telescope.

Carnegie Melon University astronomer Dustin Lang and colleagues, however, have come up with a different way to get astronomical images fit for research. It's a technique built on a simple realization: the Internet is replete with free pictures of the night sky. “The astrophotography group on Flickr alone has over 68,000 images,” said Lang to Technology Review.

To get detailed images of deep space, astronomers have a couple of options, says Technology Review. They can either use a long exposure to capture one really detailed image, or stack multiple less-detailed images together. Lang and colleagues opted for the second approach. But rather than using multiple photos taken with the same telescope, they looked to the web. 

The team used a new alogorithm to stack nearly 300* images of the Galaxy NGC 5907 that they found on Flickr, Bing, and Google. They did this by "[l]iterally searching for 'NGC 5907' and 'NGC5907'," explains Astrobites.

For a photo of the night sky to be useful, though, the scientists first needed to know exactly what they were looking at. For that they turned to Astrometry.net*, a site that pinpoints exactly which patch of the sky is shown in an image. You can add to Lang's collection--and our collective understanding of the stars--by submitting an image to Astrometry.net.

If you have astronomical imaging of the sky with celestial coordinates you do not know—or do not trust—then Astrometry.net is for you. Input an image and we'll give you back astrometric calibration meta-data, plus lists of known objects falling inside the field of view.

Once they were stacked together, the images revealed faint features that offered information on the mass, age and orbitial configurations of the celestial bodies in galaxy NGC 5907--information that was not present in a single photo. Here's Brett Deaton on Astrobites on the merits of the technique:

Recently I was so struck by the bright swath of the Milky Way that I took my fiancé’s camera and snapped a great picture of…nothing: it was too dim. 

But stitched into a map by the new algorithm, that image could say a few thousand words. The technique is a great chance for citizen scientists everywhere to contribute to real research, and a nice display of the possibilities of "big data." Technology Review calls the feat "a revolution" in astronomy, but it will probably take a little longer to see exactly what Lang, his algorithm and several thousand amateur snapshots can tell us.

*Update: The site is Astrometry.net, not Astronomy.net. Also, the scientists used 298 photos of NGC 5907, not the 5,000 previously reported.

Shannon Palus | | READ MORE

Shannon Palus is a science writer, and a researcher for Popular Science. Her work has appeared in Discover, Slate, Ars Technica, and elsewhere. She is based in Philadelphia.