Tour: NASA's Chandra Notices the Galactic Center is Venting

Using NASA’s Chandra X-ray Observatory, astronomers have located an exhaust vent attached to a “chimney” of hot gas blowing away from the center of the Milky Way galaxy. The chimney and vent are about 26,000 light-years from Earth. The chimney begins at the center of the galaxy and stands perpendicular to the Milky Way’s spiral disk.

The research team thinks that eruptions from the supermassive black hole at the Milky Way’s center called Sagittarius A* — or Sgr A* for short — may have created this chimney and exhaust vent.

Previously, other astronomers had found a structure in X-ray data from Chandra and XMM-Newton that seemed to be acting as a chimney, moving hot gas away from the center of the Galaxy. This latest result shows how this hot gas escaping into the rest of the galaxy.

The new Chandra data reveals what astronomers think are the walls of a cylindrical tunnel that is pumping hot gas into the Milky Way about 700 light-years away from Sgr A*. The researchers think this hot gas is being driven upwards when material gets dumped onto Sgr A* and causes eruptions.

It’s too early to tell just how often Sgr A* is being fed. Is this energy and heat are stoked by a large amount of material being dumped onto Sgr A* at once, like a bunch of logs being dumped on a fire at once? Or does it come from multiple small loads being fed into the black hole similar to kindling being regularly tossed in? Future observations may provide answers.

In the meantime, the discovery of this exhaust vent might point astronomers to the origin of two mysterious and much larger structures around the center of the Milky Way: the Fermi Bubbles seen in gamma-rays by NASA’s Fermi Telescope Gamma-ray Space Telescope and the eROSITA Bubbles, detected by ESA’s newest X-ray telescope. Both of these are pairs of structures extending thousands of light-years away from the center of the Galaxy.

Chandra continues to show how fascinating and complex the center of our Milky Way galaxy is.