Growing black holes are swallowing thousands of stars in space, NASA says

WASHINGTON (TND) — Black holes in space are getting bigger and stronger, according to NASA.

A new survey of more than 100 galaxies by the space agency's Chandra X-ray Observatory "has uncovered signs that black holes are demolishing thousands of stars in a quest to pack on weight."

This means those black holes are growing. NASA shared photo composites of four galaxies.

This jewel-bright image from the NASA/ESA Hubble Space Telescope shows NGC 1385, a spiral galaxy 68 million light-years away from Earth, which lies in the constellation Fornax. (Photo: NASA)

X-rays from Chandra, shown in blue, were overlaid on optical images from NASA's Hubble Space Telescope of the galaxies NGC 1385, NGC 1566, NGC 3344 and NGC 6503.

These new results suggest a somewhat violent path for at least some of these black holes to reach their present size — stellar destruction on a scale that has rarely if ever been seen before," NASA said in a news release.

The four galaxies shown in the graphic are among 29 showing evidence of growing black holes near their centers.

This new Hubble image shows NGC 1566, a beautiful galaxy located approximately 40 million light-years away in the constellation of Dorado (The Dolphinfish). NGC 1566 is an intermediate spiral galaxy, meaning that while it does not have a well-defined bar-shaped region of stars at its center — like barred spirals — it is not quite an unbarred spiral either (heic9902o). The small but extremely bright nucleus of NGC 1566 is clearly visible in this image. (Photo: NASA)

Astronomers have conducted several detailed studies through the years to distinguish black holes, generally breaking them up into two classes:

• Stellar-mass black holes – a small varietythat typically weighs 5 to 30 times the mass of Earth's Sun
  
• Supermassive black holes – these live in the middle of most large galaxies, which weigh millions or even billions of solar masses
  

Studies conducted in recent years suggest an in-between class exists and is needed for "intermediate-mass black holes," also known as IMBHs.

The new Chandra study may explain how IMBHs are formed — through the "runaway growth of stellar-mass black holes."

This image of the spiral galaxy NGC 3344, located about 20 million light-years from Earth, is a composite of images taken through seven different filters. They cover wavelengths from the ultraviolet to the optical and the near-infrared. Together they create a detailed picture of the galaxy and allow astronomers to study many different aspects of it. (Photo: NASA)

Black holes are formed by consuming clusters of unlucky stars passing within their gravitational pull, NASA said. The latest research suggests there are very dense clusters of stars at the center of some galaxies.

With stars so closely bunched together, this creates the perfect environment for IMBHs to form. Theoretical work conducted by a team of scientists implies a stellar-mass black hole will rapidly grow into an IMBH as "it pulls in, shreds and ingests the abundant neighboring stars in close proximity."

The latest study suggests this process can occur at any time in the universe's history, meaning IMBHs "can form billions of years after the Big Bang, right up to the present day."

A paper describing these results appears online in The Astrophysical Journal.