Astronomers have found the edge of the Milky Way at last

Our galaxy spans 1.9 million light-years, a new study finds

Milky Way

In this image from the Fermi space telescope, the Milky Way's stellar disk, which runs horizontally along the middle, glows in gamma rays. A vast halo of dark matter engulfs the disk and emits no light at all, which makes measuring the galaxy’s total size a challenge.

Fermi LAT collaboration/DOE/NASA

This article is only available to Science News subscribers.

Subscribers, enter your e-mail address to access our archives.

Not a subscriber?

Science News is a nonprofit.

Support us by subscribing now.

More Stories from Science News on Space

From the Nature Index

Paid Content