Tuesday, December 15, 2009

How close is the nearest black hole to Earth?

Until recently it was impossible to give an exact answer on bow close is the nearest black hole to Earth but an international team of astronomers has for the first time accurately measured the distance from Earth to a black hole, and this distance is 7800 light years, which is much closer that many scientists assumed it is.

How did they measure this distance? The breakthrough discovery was in this case the result of measuring the radio emissions from the black hole and its associated dying star. An exact distance from black hole is important from two different reasons. First of all astronomers can now gain a better picture of how black holes evolve, and what is even more important an exact distance is important for measurements of the black hole´s spin.

This nearest black hole was the result of supernova explosion, and it moves through space at a rate of about 40 km per second.

Scientists hope that with the help of this new measuring method they'll be able "to answer the question as to whether there is a difference between black holes that evolve directly from the collapse of a star without a supernova and black holes that evolve via a supernova and a temporary intermediate star, a proto-neutron star. We expect that the black holes in the last group can get a kick. Black holes formed in this way could then move through space faster", as Peter Jonker from SRON Netherlands Institute for Space Research said in his interview.