"Death Star" Galaxy Shoots Black Hole Jet at Hapless Neighbor

Here's a little lesson in parallelism. On Earth, it's a bad idea to step in front of a moving train. In space, it may be an even worse idea to step in front of the powerful jets being spewed out of a massive black hole.

With that in mind, pity the poor stepchild galaxy in the 3C321 system, which features two galaxies orbiting each other at relatively close distances.

In a virtuoso feat of cross-telescope observation, researchers using the Chandra X-ray Observatory, the Hubble Space Telescope, and the Spitzer Space Telescope, along with a others, have observed that each galaxy in the system has a massive black hole at its center – but the larger has a huge jet shooting from its center, and splashing into the smaller.

The researchers naturally are taking considerable pleasure in the finding. While expressing suitable, nearly straight-faced concern, of course:

"We've seen many jets produced by black holes, but this is the first time we've seen one punch into another galaxy like we're seeing here,"
said Dan Evans, a scientist at the Harvard-Smithsonian Center for
Astrophysics and leader of the study. "This jet could be causing all sorts of problems for the smaller galaxy it is pummeling."

Jets from black holes aren't uncommon in the wider universe, throwing out huge quantities of potentially lethal X-rays and gamma rays. But this particular configuration – estimated to be only about a million years old by astronomers – is rare indeed.

Pity any poor habitable planet in its path, too. A jet of this power would wreak havoc with planetary atmospheres, potentially destroying ozone layers, among other dastardly effects, researchers said.

However, there may be a bright – or at least a creative – side, as well. The jet's collision with the neighbor galaxy could ultimately help form large numbers of new stars and planets, after the violence of the impact dies down.

Results from the collective analysis will appear in The Astrophysical Journal.

UPDATE: Reader Steve Croft, an astrophysicist at the University of California at Berkeley, points out that this observation is not wholly unprecedented. He and colleague Wil van Breugel published a paper two years ago detailing observations of a similar black hole jet prompting star formation in its own neighboring galaxy. A *New Scientist *version of that story is here, and the Astrophysical Journal paper here.

Thanks for the note, Prof. Croft!

'Death Star' Galaxy Black Hole Fires at Neighboring Galaxy [NASA press release]

(Image: A composite image of the 3C321, pieced together from Chandra
(colored purple), optical and ultraviolet (UV), data from Hubble (red and orange), and radio emission from the Very Large Array (VLA) and
MERLIN (blue). The galaxy on the lower left is shooting its jet against the edge of the elongated galaxy on the upper right. Credit: X-ray:
NASA/CXC/CfA/D.Evans et al.; Optical/UV: NASA/STScI; Radio:
NSF/VLA/CfA/D.Evans et al., STFC/JBO/MERLIN)