Amateurs find a nearby star by looking through pro astronomers’ old data.

There’s a thing in Australia called “noodling,” where hobbyists look through opal mine spoil piles and find overlooked bits of precious stones. Syfy Wire has a report on the astronomical equivalent, with “citizen scientists” making a notable discovery in public domain images from a professional project:

Being warmish, brown dwarfs tend to emit most of their light in the infrared part of the spectrum, outside the color range our eyes can see. But we can build detectors that are sensitive to infrared, attach them to telescopes, launch them into space, and sweep the sky to see what’s out there.

Astronomers have done this, many times, including with the wonderful Wide-field Infrared Survey Explorer, or WISE, for several years starting in 2010. It looked in four different wavelengths (colors) of IR light, creating a vast catalog of objects in the sky — over three-quarters of a billion of them.

A lot of those objects were brown dwarfs. They were found in two ways: Either by their colors (they tend to emit light at a specific IR color, making them stand out in WISE images) or by their motion. Brown dwarfs are extremely faint, so we only see ones that are relatively nearby the Sun (like, out to 100 light-years away or so). Because they’re close, their motion in space as they orbit the galaxy means we can see them move over time … it’s just like nearby trees seem to whiz past you when you’re in a car, when more distant object appear to move more slowly. Finding moving brown dwarfs is hard; they’re faint and look little more than blips in the images. This makes automating the search difficult (computers are easy to fool). But the human eye is good at seeing such things! And such a task doesn’t need a lot of training, either.

That’s why the folks at Zooniverse decided to take this on. This is a group of astronomers and researchers who figured out that non-scientists can not only participate in scientific research but also give a meaningful contribution to it as well.

Called Back Yard Worlds, it blinks four images from WISE observations taken of the same part of the sky at different times. The images have been processed a bit, subtracting one from another, so that fixed objects like stars and galaxies are suppressed, hopefully leaving behind moving targets. Your task: Look for the things that change. It’s not easy; I just tried it and there are lots of things that can fool the eye. But if enough people look at enough images, things turn up.

And something did: On February 1, 2017, less than a week after the launch of Back Yard Worlds, a user spotted what looked like a slowly moving object.

It has been dubbed WISEA J110125.95+540052.8 (after its coordinates in the sky), and it’s about 110 light-years away. Not much is known about it except that it has a spectral type of T5.5, meaning it’s an intermediate mass and cool brown dwarf (with a temperature of very roughly 650-1250°C, much cooler than the Sun).

[via Bad Astronomer]

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