Neil Gehrels Swift Observatory

Neil Gehrels Swift Observatory
Neil Gehrels Swift Observatory
NamesExplorer-84
MIDEX-3
Swift Gamma Ray Burst Explorer
Mission typeGamma-ray astronomy
OperatorNASA / Pennsylvania State University
COSPAR ID2004-047A
SATCAT no.28485
Websiteswift.gsfc.nasa.gov
Mission duration2 years (planned)
21 years, 3 months, 23 days (in progress)
Spacecraft properties
SpacecraftExplorer LXXXIV
Spacecraft typeSwift Gamma Ray Burst Explorer
BusLEOStar-3
ManufacturerSpectrum Astro
Launch mass1,470 kg (3,240 lb)
Dry mass613 kg (1,351 lb)
Payload mass843 kg (1,858 lb)
Dimensions5.6 × 5.4 m (18 × 18 ft)
Power1040 watts
Start of mission
Launch date20 November 2004, 17:16:01 UTC
RocketDelta II 7320-10C (Delta 309)
Launch siteCape Canaveral, SLC-17A
ContractorBoeing Defense, Space & Security
Entered service1 February 2005
Orbital parameters
Reference systemGeocentric orbit
RegimeLow Earth orbit
Perigee altitude585 km (364 mi)
Apogee altitude604 km (375 mi)
Inclination20.60°
Period96.60 minutes
Instruments
Burst Alert Telescope (BAT)
UltraViolet Optical Telescope (UVOT)
X-Ray Telescope (XRT)

Swift Gamma Ray Burst Explorer
Explorer program

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 burst detection rate is 100 per year, with a sensitivity ~3 times greater than the BATSE detector aboard the Compton Gamma Ray Observatory. The Swift mission was launched with a nominal on-orbit lifetime of two years. Swift is a NASA MIDEX (medium-class Explorer) mission, operated by Pennsylvania State University. It was the third to be launched, following IMAGE and WMAP.

While originally designed for the study of gamma-ray bursts, Swift now functions as a general-purpose multi-wavelength observatory, particularly for the rapid follow-up and characterization of astrophysical transients of all types. As of 2020, Swift received 5.5 Target of Opportunity observing proposals per day, and observes ~70 targets per day, on average.