Discovered: A Bridge Between Galaxy Clusters

More

The ESA's Planck observatory finds a connection between Abell 399 and Abell 401.

[optional image description]
Two galaxy clusters, Abell 399 (lower center) and Abell 401 (top left), are connected by a bridge of hot gas. (Sunyaev-Zel'dovich effect: ESA Planck Collaboration; optical image: STScI Digitized Sky Survey)

About a billion light years away from us here on Earth, there are two galaxy clusters, Abell 399 and Abell 401. Those clusters are distant, and not just from us, but from each other: They are located some 10 million light years apart. But those clusters are also, it turns out, connected -- through a bridge, composed of hot gas, that conjoins them across space. Planck, the European Space Agency space observatory, made the discovery.

Shown above are Abell 399 and Abell 401, as seen at optical wavelengths through ground-based telescopes -- and as observed by Planck. The orange coloring indicates the presence of the Sunyaev-Zel'dovich effect, which causes a change in the apparent brightness of the cosmic microwave background radiation between stars and galaxies (and, for that matter, between any other reservoirs of hot plasma out there in the universe).

The bridge Planck discovered could be evidence that the galaxy clusters in question passed by each other many, many ages ago. That was the going theory, at least, when a similar gas bridge -- a stream of hydrogen -- was discovered this summer, this one connecting the colossal Andromeda Galaxy, M31, and its neighboring Triangulum Galaxy, M33. "The properties of this gas indicate that these two galaxies may have passed close together in the distant past," Jay Lockman, of the National Radio Astronomy Observatory, said of that discovery. "Studying what may be a gaseous link between the two can give us a new key to understanding the evolution of both galaxies."

Jump to comments
Presented by

Megan Garber is a staff writer at The Atlantic. She was formerly an assistant editor at the Nieman Journalism Lab, where she wrote about innovations in the media.

Get Today's Top Stories in Your Inbox (preview)

A Technicolor Time-Lapse of Alaska's Northern Lights

The beauty of aurora borealis, as seen from America's last frontier


Join the Discussion

After you comment, click Post. If you’re not already logged in you will be asked to log in or register. blog comments powered by Disqus

Video

A Time-Lapse of Alaska's Northern Lights

The beauty of aurora borealis, as seen from America's last frontier

Video

What Do You Wish You Learned in College?

Ivy League academics reveal their undergrad regrets

Video

Famous Movies, Reimagined

From Apocalypse Now to The Lord of the Rings, this clever video puts a new spin on Hollywood's greatest hits.

Video

What Is a City?

Cities are like nothing else on Earth.

Video

CrossFit Versus Yoga: Choose a Side

How a workout becomes a social identity

Video

In Online Dating, Everyone's a Little Bit Racist

The co-founder of OKCupid shares findings from his analysis of millions of users' data.

Writers

Up
Down

More in Technology

Just In