The LARGEST BLACK HOLE Ever

A giant black hole weighing a staggering 6.6 billion suns accepted the title of the most massive black hole for which a precise mass has been determined.

That’s not to say it’s necessarily the largest black hole in the universe by any means, but in this neck of the cosmic woods we haven’t measured a bigger one. Located at the heart of the galaxy M87 some 50 million light years away in the direction of Virgo, the black hole is so big it could swallow our solar system hole easily.

Previous estimates of M87’s black hole mass registered at some 3 billion suns, still 1,000 times the size of the Milky Way’s welterweight black hole. The new measurements were acquired using the adaptive optics capabilities on the 26.6-foot Frederick C. Gillett Gemini Telescope on Mauna Kea, Hawaii, which can compensate for the distorting effects of Earth’s atmosphere. This allowed astronomers to gauge just how fast the stars in M87 are orbiting the black hole, and from that they could determine the mass.

Whether M87’s black hole achieved its mass fairly or not, it may not hold the heavyweight title for very long anyhow. Over the next decade astronomers plan to hook up telescopes all over the world to create a whole Earth submillimeter array that will vastly increase their ability to locate event horizons and characterize the size of black holes throughout the universe.

We’d be surprised if there wasn’t some young black hole out there right now devouring its surroundings and merging with smaller counterparts in hopes of one day unseating the champ.

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When the BLACK HOLE Was BORN

Most galaxies in the universe, including our own Milky Way, harbor super-massive black holes varying in mass from about one million to about 10 billion times the size of our sun.

To find them, astronomers look for the enormous amount of radiation emitted by gas which falls into such objects during the times that the black holes are "active". This gas "infall" into massive black holes is believed to be the means by which black holes grow.

Now a team of astronomers from Tel Aviv University, including Prof. Hagai Netzer and his research student Benny Trakhtenbrot, has determined that the era of first fast growth of the most massive black holes occurred when the universe was only about 1.2 billion years old -- not two to four billion years old, as was previously believed -- and they're growing at a very fast rate.

The oldest are growing the fastest

The new research is based on observations with some of the largest ground-based telescopes in the world: "Gemini North" on top of Mauna Kea in Hawaii, and the "Very Large Telescope Array" on Cerro Paranal in Chile. The data obtained with the advanced instrumentation on these telescopes show that the black holes that were active when the universe was 1.2 billion years old are about ten times smaller than the most massive black holes that are seen at later times. However, they are growing much faster.

The measured rate of growth allowed the researchers to estimate what happened to these objects at much earlier as well as much later times. The team found that the very first black holes, those that started the entire growth process when the universe was only several hundred million years old, had masses of only 100-1000 times the mass of the sun. Such black holes may be related to the very first stars in the universe. They also found that the subsequent growth period of the observed sources, after the first 1.2 billion years, lasted only 100-200 million years.

The new study is the culmination of a seven year-long project at Tel Aviv University designed to follow the evolution of the most massive black holes and compare them with the evolution of the galaxies in which such objects reside.

Other researchers on the project include Prof. Ohad Shemmer of the University of North Texas, who took part in the earlier stage of the project as a Ph.D student at Tel Aviv University, and Prof. Paulina Lira, from the University of Chile.

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DARK ENERGY, the greatest discovery of modern astronomy in the last 100 years

Dark Energy it has been discovered using the Hubble constant and measurements of supernovae of distant stars that the universe is not contracting, nor is it static (as Einstein thought), but instead, the universe is expanding, and the expansion is speeding up.

To account for this, a hypothetical form of energy known as Dark Energy has been proposed and is being investigated by leading astrophysicists and cosmologists.

Whether it is a scalar property of space time itself, as proposed through a cosmological constant, or something dynamic, known as quintessence, is a matter of large debate, but current astrophysics places a full 74% of the energy in the universe as being dark energy.

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