152 Gamma-Ray Bursts (GRBs)

During the 1960s, there was great concern among the Superpower Countries that nuclear testing or even a nuclear attack could occur without notice. The United States developed a series of satellites to monitor gamma radiation pulses emitted by nuclear weapons tested or used in space. Gamma radiation outbursts were observed and determined to be coming from space. Further research showed these outbursts were fairly evenly distributed throughout the sky.Gamma-ray bursts , or GRBs , are flashes of gamma radiation related to extreme energetic explosions detected in very distant galaxies. GRBs are the brightest electromagnetic events known to occur in the Universe. These GRBs can range from ten milliseconds to several minutes. The initial GRB is usually followed by a longer lived afterglow, emitted at wavelengths such as X-ray, UV, visual, microwave, and radio wavelengths.

A number of satellites have been built to observe GRBs. The Compton Gamma Ray Observatory determined that GRBs were from outside our Galaxy. (There is a class of gamma-ray objects within our galaxy, but not with the extreme power of GRBs). Some have speculated that GRBs are possibly at the edge of the early Universe and the death throes of extremely massive stars, which only lasted about 1 million years. These stars appear to eject Gamma Rays after a hypernova event , an extreme supernova which produces gamma radiation. GRBs also appear to come from within stellar nurseries.

A Gamma-ray burst; GRB 1306038, over a period of about three weeks, showing how the GRB faded in that period of time. In the image at left, the galaxy in the center produced the gamma-ray burst, designated GRB 130603B. The galaxy, cataloged as SDS J112848.22+170418.5, resides almost 4 billion light-years away. A probe of the galaxy with Hubble's Wide Field Camera 3 on June 13, 2013, revealed a glow in near-infrared light at the source of the gamma-ray burst, shown in the image at top, right. When Hubble observed the same location on July 3, the source had faded, shown in the image at below, right. The fading glow provided key evidence that it was the decaying fireball of a new type of stellar blast called a kilonova.
Public Domain | Image courtesy of NASA, ESA, N. Tanvir (University of Leicester), A. Fruchter (STScI), and A. Levan (University of Warwick).

Consider this…

“The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff.”

—Dr. Carl Sagan Cosmos (2002)


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