GRB 130427A was a record-setting

gamma-ray burst In gamma-ray astronomy, gamma-ray bursts (GRBs) are immensely energetic explosions that have been observed in distant galaxies. They are the most energetic and luminous electromagnetic events since the Big Bang. Bursts can last from ten millise ...

, discovered starting on April 27, 2013.ASA's Fermi, Swift See 'Shockingly Bright' Burst 05.03.13
/ref> This GRB was associated to SN 2013cq, of which the appearance of optical signal was predicted on May 2, 2013 and detected on May 13, 2013. The '' Fermi'' space observatory detected a

gamma-ray A gamma ray, also known as gamma radiation (symbol γ or \gamma), is a penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nuclei. It consists of the shortest wavelength electromagnetic waves, typically sh ...

with an energy of at least 94 billion electron volts. It was simultaneously detected by the Burst Alert Telescope aboard the ''

Swift Swift or SWIFT most commonly refers to: * SWIFT, an international organization facilitating transactions between banks ** SWIFT code * Swift (programming language) * Swift (bird), a family of birds It may also refer to: Organizations * SWIFT, ...

'' telescope and was the brightest burst Swift had ever detected. It was one of the five closest GRBs, at about 3.6 billion light-years away, and was comparatively long-lasting.

space observatory also observed the burst, quickly determining its location. The X-ray afterglow of the burst was so bright that Swift was able to observe it for the next six months. The emission was also detected using radio, infrared and visible radiation from ground-based telescopes using the sky location from Swift. The burst was observed with a 350mm optical telescope and its brightness measured. The visible

apparent magnitude Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's ...

decreased from 13 to 15.5 over a three-hour period starting at 08:05:12 UTC 27 April 2013. The Catalina Real-time Transient Survey also detected the burst optically, independent of the alert. It received designation CSS130502:113233+274156. It was found at right ascension 11:32:32.90, and declination +27:41:56.5 (J2000). The SDSS catalogue shows a galaxy (SDSS J113232.84+274155.4) almost coincident with this position at magnitude ''r''=21.26 but with no SDSS spectrum obtained.

References

{{2013 in space 130427A 20130427 April 2013 events Leo (constellation)