GRB tagged posts

Magnetic fingerprint of a cosmic explosion detected for the first time

This illustration depicts Faraday rotation in the afterglow of a gamma-ray burst. A powerful jet (upper left) sends polarized radio waves outward through the thin wall of a surrounding bubble of magnetized gas called an HII region. As the light passes through this material, its polarization angle is twisted by the magnetic field. Because the effect is stronger at longer wavelengths, the red and blue waves, which represent different radio wavelengths, exit the bubble oscillating in different directions. By measuring this difference, astronomers were able to map the magnetic environment surrounding GRB 260310A for the first time.
Credit: NSF/AUI/NSF NRAO/M.Weiss

Astronomers have made a series of landmark observations of one of the universe’s most violent events. Using the U.S...

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Measuring the Universe with Star-Shattering Explosions

Conceptual image of this research: using Gamma Ray Bursts to determine distance in space. (Credit: NAOJ)

An international team of 23 researchers led by Maria Dainotti, Assistant Professor at the National Astronomical Observatory of Japan (NAOJ), has analyzed archive data for powerful cosmic explosions from the deaths of stars and found a new way to measure distances in the distant Universe.

With no landmarks in space, it is very difficult to get a sense of depth. One technique astronomers use is to look for “standard candles,” objects or events where the underlying physics dictate that the absolute brightness (what you would see if you were right next to it) is always the same...

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Radio Observations confirm Superfast Jet of material from Neutron Star Merger

Aftermath of the merger of two neutron stars. Ejecta from an initial explosion formed a shell around the black hole formed from the merger. A jet of material propelled from a disk surrounding the black hole first interacted with the ejecta material to form a broad "cocoon." Later, the jet broke through to emerge into interstellar space, where its extremely fast motion became apparent. Credit: Sophia Dagnello, NRAO/AUI/NSF

Aftermath of the merger of two neutron stars. Ejecta from an initial explosion formed a shell around the black hole formed from the merger. A jet of material propelled from a disk surrounding the black hole first interacted with the ejecta material to form a broad “cocoon.” Later, the jet broke through to emerge into interstellar space, where its extremely fast motion became apparent.
Credit: Sophia Dagnello, NRAO/AUI/NSF

Jet appeared to move 4X faster than light. The supersharp radio ‘vision’ of a continent-wide collection of radio telescopes has answered an outstanding question about the aftermath of a merger of two neutron stars...

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Gamma-Ray GRB Afterglow Brighter Than an Entire Galaxy: “A Window Into the Young Universe”

Nebula-jet_still_1

Gamma ray bursts (GRBs) – flashes of high-energy light occur about once a day, randomly, from around the sky – the brightest events in the known universe. While a burst is underway, it is many millions of times brighter than an entire galaxy. Astronomers are anxious to decipher their nature not only because of their dramatic energetics, but also because their tremendous brightness enables them to be seen across cosmological distances and times, providing windows into the young universe.

GRB 130427A tops the charts as one of the brightest ever seen.
There appear to be 2 general types of GRBs: those associated with the deaths of massive stars, and ones believed to originate from the coalescence of 2 extreme objects (neutron stars or black holes) that had been orbiting each other in a binary...

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