The faraway star clusters on the other side of the galaxy

Illustration for article titled The faraway star clusters on the other side of the galaxy

That bright explosion of stars on the right is a globular star cluster, one of just 160 such clusters in the galaxy. It's making its big debut after long being hidden behind the dust of the center of the galaxy.


Believe it or not, that star cluster was once the dimmest known globular cluster, which are collections of stars in a spherical arrangement that orbit galactic cores. Known as UKS1, this cluster is located on the other side of the Milky Way. That's why it was so dim before, as the interstellar dust between it and us absorbed and stretched most of the starlight. The only way to see it properly is to look in the infrared wavelength, and thanks to the European Southern Observatory's VISTA survey telescope, we're now finally able to view it in its full glory.

However, that isn't the only distant globular cluster in this image. If you can see the bright light source on the left side of the image...well, that isn't it. Instead, look up and to the right at a 45 degree angle from it, and you should be able to see a second, far smaller cluster of stars. That's VVV CL001, and it's possible that it's actually gravitationally bound to UKS1. If that's true, we're looking at the first binary globular cluster system in the galaxy. That, however, might just be an optical illusion created by where they're located in this image - it's entirely possible that they're nowhere near each other.

For more, including another photo that reveals yet another new globular cluster, check out the ESO website.


imaginary friend

this is your big debut

sure looks good on you