This composite image shows a supernova within the galaxy M100 that may contain the youngest known black hole in our cosmic neighborhood. In this image, Chandra’s X-rays are colored gold, while optical data from ESO’s Very Large Telescope are shown in yellow-white and blue, and infrared data from Spitzer are red. The supernova is marked with a green circle.
SN 1979C was first reported to be seen by an amateur astronomer in 1979. The galaxy M100 is located in the Virgo Cluster about 50 million light years from Earth. This approximately 30-year age, plus its relatively close distance, makes SN 1979C the nearest example where the birth of a black hole has been observed, if the interpretation by the scientists is correct.
Data from Chandra, as well as NASA’s Swift, the European Space Agency’s XMM-Newton and the German ROSAT observatory revealed a bright source of X-rays that has remained steady for the 12 years from 1995 to 2007 over which it has been observed. This behavior and the X-ray spectrum, or distribution of X-rays with energy, support the idea that the object in SN 1979C is a black hole being fed either by material falling back into the black hole after the supernova, or from a binary companion.
The scientists think that SN 1979C formed when a star about 20 times more massive than the Sun collapsed. It was a particular type of supernova where the exploded star had ejected some, but not all of its outer, hydrogen-rich envelope before the explosion, so it is unlikely to have been associated with a gamma-ray burst (GRB). Supernovas have sometimes been associated with GRBs, but only where the exploded star had completely lost its hydrogen envelope. Since most black holes should form when the core of a star collapses and a gamma-ray burst is not produced, this may be the first time that the common way of making a black hole has been observed.
Credit X-ray: NASA/CXC/SAO/D.Patnaude et al, Optical: ESO/VLT, Infrared: NASA/JPL/Caltech
Flying along the Vela ridge
A beautiful blue butterfly flutters towards a nest of warm dust and gas, above an intricate network of cool filaments in this image of the Vela C region by ESA’s Herschel space observatory.
Vela C is the most massive of the four parts of the Vela complex, a massive star nursery just 2300 light-years from the Sun. It is an ideal natural laboratory for us to study the birth of stars.
Herschel’s far-infrared detectors can spot regions where young high and low-mass stars have heated dense clumps of gas and dust, where new generations of stars may be born.
The eye is immediately drawn to two prominent features in this image: a delicate blue and yellow butterfly shape just right of centre that appears to be flying towards a nest of coiled blue material in the lower right.
These regions stand out from their surroundings because their dust has been heated by young hot stars. A cluster of very hot, massive stars are strung out along the butterfly’s ‘body’, their radiation heating up the surrounding dust seen as yellow in this scene.
These heavy stars will follow ‘live fast, die young’, burning brightly for only a short time in cosmic terms. Those with more than eight times the mass of our own Sun will explode as cataclysmic supernovas within 10 million years of forming.
A particularly dense trunk of cool gas and dust weaves its way through the centre of the image, surrounded by a complex network of wispy red filaments.
Deeply embedded inside the filaments are numerous point-like sources, particularly evident towards the left of the scene: these are protostars, the seeds of new stars that will soon also light up the Vela region of the sky.
Credits: ESA/PACS & SPIRE Consortia, T. Hill, F. Motte, Laboratoire AIM Paris-Saclay, CEA/IRFU – CNRS/INSU – Uni. Paris Diderot, HOBYS Key Programme Consortium
Signals of a Strange Universe
Credit: High-Z Supernova Search Team, HST, NASA
A Supernova Cocoon Breakthrough
On November 3, 2010, a supernova was discovered in the galaxy UGC 5189A, located about 160 million light years away. Using data from the All Sky Automated Survey telescope in Hawaii taken earlier, astronomers determined this supernova exploded in early October 2010 (in Earth’s time-frame).
This composite image of UGC 5189A shows X-ray data from Chandra in purple and optical data from Hubble Space Telescope in red, green and blue. SN 2010jl is the very bright X-ray source near the top of the galaxy. A team of researchers used Chandra to observe this supernova, which was one of the most luminous that has ever been detected in X-rays.
The X-rays from the explosion’s blast wave were strongly absorbed by a cocoon of dense gas around the supernova, which was formed by gas blown away from the massive star before it exploded. Then, the blast wave from the explosion broke out of the cocoon and heated the surrounding gas to very high temperatures — greater than 100 million °K — making it glow in X-rays.
In short, the matter around the supernova has been heated and ionized (electrons stripped from atoms) by the X-rays generated when the blast wave plows through this material. This discovery therefore supports the idea that some of the unusually luminous supernovas are caused by the blast wave from their explosion ramming into the material around it.
With springtime in full swing for the Northern Hemisphere, you may be able to hear the chirping of recently-hatched chicks wrapped snugly in their nests. But for Messier 78, a reflection nebula near the famous Orion’s Belt, springtime has been erupting for millions of years inside a cocoon of thick, choking smog. Messier 78’s ‘spring’ won’t end until its gas and dust has either been blown away or consumed by the voracious appetites of the clutch of baby stars it hides.