TWINS

This article is about the NASA instruments on Earth satellites. For the meteorological instruments on NASA's InSight Mars lander, see Temperature and Winds for InSight. For other uses of "Twins", see Twins (disambiguation).

TWINS
TWINS 1 and TWINS 2 in simultaneous Molniya orbits, obtain stereo images of the Earth's ring current, including signals from both trapped ions and precipitating ions.
OperatorNASA
Instrument typeSpectrometer
FunctionMagnetospheric
Mission duration2 years (planned)
Websitehttp://twins.swri.edu/index.jsp
Properties
Number launched2
Host spacecraft
SpacecraftUSA-184
USA-200
OperatorNRO
OrbitMolniya

Two Wide-Angle Imaging Neutral-Atom Spectrometers (TWINS) are a pair of NASA instruments aboard two United States National Reconnaissance Office (NRO) satellites in Molniya orbits. TWINS was designed to provide stereo images of the Earth's ring current. The first instrument, TWINS-1, was launched aboard USA-184 on 28 June 2006. TWINS-2 followed aboard USA-200 on 13 March 2008.

Each instrument consists of an energetic neutral atom imager and a Lyman alpha detector. The ENA imager provides indirect remote sensing of the ring current ions, and the Lyman alpha detector gives a measure of the neutral hydrogen cloud about the Earth, known as the geocorona. The TWINS prime mission lasted two years, from 2008 to 2010, and has been followed by an extended mission which is ongoing.[1]

  1. ^ "Five Years of Stereo Imaging for NASA's TWINS". NASA. 24 June 2013. Retrieved 3 May 2018. Public Domain This article incorporates text from this source, which is in the public domain.