In gamma-ray astronomy, gamma-ray bursts (GRBs) are immensely energetic explosions that have been observed in distant galaxies, being the brightest and most extreme explosive events in the entire universe, as NASA describes the bursts as the "most powerful class of explosions in the universe". They are the most energetic and luminous electromagnetic events since the Big Bang. Gamma-ray bursts can last from ten milliseconds to several hours. After the initial flash of gamma rays, an "afterglow" is emitted, which is longer lived and usually emitted at longer wavelengths.
The Compton Gamma Ray Observatory (CGRO) was a space observatory detecting photons with energies from 20 keV to 30 GeV, in Earth orbit from 1991 to 2000. The observatory featured four main telescopes in one spacecraft, covering X-rays and gamma rays, including various specialized sub-instruments and detectors. Following 14 years of effort, the observatory was launched from Space Shuttle Atlantis during STS-37 on April 5, 1991, and operated until its deorbit on June 4, 2000. It was deployed in low Earth orbit at 450 km (280 mi) to avoid the Van Allen radiation belt. It was the heaviest astrophysical payload ever flown at that time at 16,300 kilograms (35,900 lb).
A robotic telescope is an astronomical telescope and detector system that makes observations without the intervention of a human. In astronomical disciplines, a telescope qualifies as robotic if it makes those observations without being operated by a human, even if a human has to initiate the observations at the beginning of the night or end them in the morning. It may have software agents using artificial intelligence that assist in various ways such as automatic scheduling. A robotic telescope is distinct from a remote telescope, though an instrument can be both robotic and remote.
Neil Gehrels Swift Observatory, previously called the Swift Gamma-Ray Burst Explorer, is a NASA three-telescope space observatory for studying gamma-ray bursts (GRBs) and monitoring the afterglow in X-ray, and UV/Visible light at the location of a burst. It was launched on 20 November 2004, aboard a Delta II launch vehicle. Headed by principal investigator Neil Gehrels until his death in February 2017, the mission was developed in a joint partnership between Goddard Space Flight Center (GSFC) and an international consortium from the United States, United Kingdom, and Italy. The mission is operated by Pennsylvania State University as part of NASA's Medium Explorer program (MIDEX).
GRB 970228 was the first gamma-ray burst (GRB) for which an afterglow was observed. It was detected on 28 February 1997 at 02:58 UTC. Since 1993, physicists had predicted GRBs to be followed by a lower-energy afterglow, but until this event, GRBs had only been observed in highly luminous bursts of high-energy gamma rays ; this resulted in large positional uncertainties which left their nature very unclear.
BOOTES is a global network of robotic astronomical observatories with seven sites located in Spain, New Zealand, China, Mexico, South Africa and Chile. While the BOOTES-1 station in Spain is devoted to wide-field astronomy, the additional stations include a similar setup : the 0.6m diameter robotic telescope, the EMCCD camera at the Cassegrain focus and the u'g'r'i'ZY filterset, which makes the BOOTES Network a unique resource for combining the data from all the instruments worldwide.
The InterPlanetary Network (IPN) is a group of spacecraft equipped with gamma ray burst (GRB) detectors. By timing the arrival of a burst at several spacecraft, its precise location can be found. The precision for determining the direction of a GRB in the sky is improved by increasing the spacing of the detectors, and also by more accurate timing of the reception. Typical spacecraft baselines of about one AU and time resolutions of tens of milliseconds can determine a burst location within several arcminutes, allowing follow-up observations with other telescopes.
GRB 080319B was a gamma-ray burst (GRB) detected by the Swift satellite at 6:12 UTC on March 19, 2008. The burst set a new record for the farthest object that was observable with the naked eye: it had a peak visual apparent magnitude of 5.7 and remained visible to human eyes for approximately 30 seconds. The magnitude was brighter than 9.0 for approximately 60 seconds. If viewed from 1 AU away, it would have had a peak apparent magnitude of −67.57. It had an absolute magnitude of −38.6, beaten by GRB 220101A with −39.4 in 2023.
GRB 970508 was a gamma-ray burst (GRB) detected on May 8, 1997, at 21:42 UTC; it is historically important as the second GRB with a detected afterglow at other wavelengths, the first to have a direct redshift measurement of the afterglow, and the first to be detected at radio wavelengths.
GRB 050709 was a gamma-ray burst (GRB) detected on July 9, 2005. A gamma-ray burst is a highly luminous flash of gamma rays, the most energetic form of electromagnetic radiation, which is often followed by a longer-lived "afterglow" emitting at longer wavelengths.
GRB 991216, nicknamed the Beethoven Burst by Dr. Brad Schaefer of Yale University, was a gamma-ray burst observed on December 16, 1999, coinciding with the 229th anniversary of Ludwig van Beethoven's birth. A gamma-ray burst is a highly luminous flash associated with an explosion in a distant galaxy and producing gamma rays, the most energetic form of electromagnetic radiation, and often followed by a longer-lived "afterglow" emitted at longer wavelengths.
GRB 000131 was a gamma-ray burst (GRB) that was detected on 31 January 2000 at 14:59 UTC. A gamma-ray burst is a highly luminous flash associated with an explosion in a distant galaxy and producing gamma rays, the most energetic form of electromagnetic radiation, and often followed by a longer-lived "afterglow" emitted at longer wavelengths.
GRB 070714B was a gamma-ray burst (GRB) that was detected on 14 July 2007 at 4:59 UTC. A gamma-ray burst is a highly luminous flash associated with an explosion in a distant galaxy and producing gamma rays, the most energetic form of electromagnetic radiation, and often followed by a longer-lived "afterglow" emitted at longer wavelengths.
Fenton Hill Observatory is an astronomical research facility operated by Los Alamos National Laboratory in the Jemez Mountains of New Mexico, about 35 miles (56 km) west of Los Alamos. The site is home to several astronomical experiments and observatories spanning 30 acres (120,000 m2). It is also known as Technical Area 57 (TA-57) and is located at an elevation of 8,700 feet (2,700 m) in a region shielded from light pollution. Los Alamos National Laboratory has a use agreement with the Forest Service for the 30 acres (120,000 m2), which is located near Fenton Lake State Park.
The Robotic Optical Transient Search Experiment (ROTSE) is a multi-telescope experiment designed to observe the optical afterglow of gamma-ray bursts. The experiment currently consists of four telescopes located in Australia, Namibia, Turkey, and at the McDonald Observatory near Fort Davis, Texas.
GRB 090429B was a gamma-ray burst observed on 29 April 2009 by the Burst Alert Telescope aboard the Swift satellite. The burst triggered a standard burst-response observation sequence, which started 106 seconds after the burst. The X-ray telescope aboard the satellite identified an uncatalogued fading source. No optical or UV counterpart was seen in the UV–optical telescope. Around 2.5 hours after the burst trigger, a series of observations was carried out by the Gemini North telescope, which detected a bright object in the infrared part of the spectrum. No evidence of a host galaxy was found either by Gemini North or by the Hubble Space Telescope. Though this burst was detected in 2009, it was not until May 2011 that its distance estimate of 13.14 billion light-years was announced. With 90% likelihood, the burst had a photometric redshift greater than z = 9.06, which would make it the most distant GRB known, although the error bar on this estimate is large, providing a lower limit of z > 7.
The Livermore Optical Transient Imaging System, or LOTIS, is an automated telescope designed to slew very rapidly to the location of gamma-ray bursts (GRBs), to enable the simultaneous measurement of optical counterparts. Since GRBs can occur anywhere in the sky, are often poorly localized, and fade very quickly, this implies very rapid slewing and a wide field of view. To achieve the needed response time, LOTIS was fully automated and connected via Internet socket to the Gamma-ray Burst Coordinates Network. This network analyzes telemetry from satellite such as HETE-2 and Swift Gamma-Ray Burst Mission and delivers GRB coordinate information in real-time. The optics were built from 4 commercial tele-photo lenses of 11 cm aperture, with custom 2048 X 2048 CCD cameras, and could view a 17.6 X 17.6 degree field.
GRB 130427A was a record-setting gamma-ray burst, discovered starting on April 27, 2013. 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 with an energy of at least 94 billion electron volts. It was simultaneously detected by the Burst Alert Telescope aboard the 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.
Fermi's Large Area Telescope (LAT) recorded one gamma ray with an energy of at least 94 billion electron volts (GeV), or some 35 billion times the energy of visible light, and about three times greater than the LAT's previous record. The GeV emission from the burst lasted for hours, and it remained detectable by the LAT for the better part of a day, setting a new record for the longest gamma-ray emission from a GRB.
The Space Variable Objects Monitor (SVOM) is a small X-ray telescope satellite developed by China National Space Administration (CNSA), Chinese Academy of Sciences (CAS) and the French Space Agency (CNES), launched on 22 June 2024.
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