At the center of our galaxy resides an invisible monster — a dark giant composed of the shredded and swallowed remains of stars, nebulae and solar systems. It has captured enormous nearby stars into orbit, causing them to whip around the galactic center at breakneck speeds until they too become just another snack.
It may sound like science fiction, but all observations indicate it's indeed a fact: A supermassive black hole, called Sagittarius A*, exists. It's real, it's huge and it's hungry.
And astronomers have just spotted its next meal.
Packed into a space less than the distance between Earth and the sun, Sgr A* is estimated to contain a mass equivalent to 4 million suns. Although it's invisible, the effect of its gravity on surrounding stars has been seen, some of which orbit this monstrous black hole at speeds of more than 600 miles per second!
Recently, researchers from the Max Planck Institute for Extraterrestrial Physics and UCLA, using the European Southern Observatory's Very Large Telescope, have been tracking a cloud of cool ionized gas approaching Sgr A*. The cloud is about three times Earth's mass and has been accelerating toward the black hole’s accretion disc for the past several years.
Powerful tidal forces have already begun to tear the cloud apart.
The mind-boggling ESO video below takes us on a tour deep into the heart of the Milky Way, where Sgr A* resides, 26,000 light-years from our relatively peaceful solar system:
There we can see the massive stars caught in complex orbits around an invisible yet incredibly powerful gravitational source, as well as the steady approach of the gas cloud.
The cloud is expected to reach Sgr A*’s event horizon in 2013, and over the subsequent few years the research team will be able to see exactly what happens when a supermassive black hole feeds. This will be the first time such an event will be witnessed from start to an expectedly messy finish.
The team's paper was published in this week’s issue of the journal Nature. Read more in the ESO's press release here.
Video credit: ESO/MPE/Nick Risinger (skysurvey.org)/VISTA/J. Emerson/Digitized Sky Survey 2 Music: xxx