The center of our galaxy is a very busy place, and it has been under close scrutiny by astronomers since 1992. A team of astronomers have been watching our galactic core, peering through the veil of dust that shrouds the core using infrared eyes via the European Southern Observatory’s New Technology Telescope and the Very Large Telescope. What they’ve seen shows a group of stars doing a mesmerizing dance around an object that we can not see, but has a definite influence on their orbits. The following video from ESO gives a great introduction to this amazing phenomena.

(http://www.eso.org/public/news/eso0846/)

A black hole? Like the saying goes – “If it walks like a duck, quacks like a duck and looks like a duck, it’s probably a duck!” The motion of these stars and other information gathered over the years indicates that there should be an object at the center of our galaxy with a mass equivalent to about 4 million Suns. Based on the latest theories, this should be a black hole.

Recently, Dr. Reinhard Genzel of the Max-Planck Institute and his team have discovered a cloud of dust and gas that appears to be heading for a close encounter with this object dominating our galactic center. The dust cloud, which is about three times as massive as the Earth, has doubled its speed over the last seven years, not something an object can do unless it has its own propulsion system or it is in a substantial gravity well – i.e. in the grip of a black hole. Astronomers predict that the cloud will pass by the black hole at a distance of about 40 billion kilometers – equivalent to about ten times the distance between the Sun and Neptune. The following video shows the time-lapse motion of the cloud as well as stars at the core.
 

Credit: ESO/MPE/M. Schartmann/L. Calçada (http://www.eso.org/public/videos/eso1151f/)

Although the cloud is being ravaged by the black hole now, in 2013 it should be at its closest to the black hole and be ripped apart. This encounter should be indicated by a brightening of this region, especially in X-ray portion of the spectrum, as the dust and gas particles are heated to millions of degrees as they collide with each other while spiraling down to the event horizon of the black hole and beyond.
 
The following video shows a simulation of the cloud in red/yellow as it approaches the black hole. The time frame is from the year 2000 to 2043.

Credit: ESO/MPE/M. Schartmann/L. Calçada (http://www.eso.org/public/videos/eso1151e/)
 
This will be a great opportunity to see a black hole feeding, as well as testing Einstein’s General Theory of Relativity as it applies to black holes. We can look forward to some celestial fireworks in 2013!
 
For more information, videos and images check out the ESO’s web site.
 
Till next time,
 

RC Davison