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LUX dark matter detector

Detecting dark matter

The kind of matter and energy we can see and touch – whether it is in the form of atoms and molecules, or heat and light, only forms a tiny proportion of the content of the Universe, only about 5%. Over a quarter is dark matter, which is totally invisible but whose gravitational attraction can be detected; while over two thirds is dark energy, a force that pushes the Universe to expand ever faster.

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Sunjammer team to present latest solar sail technology

11 June 2013

Sunjammer probe. Credit: NASA
Sunjammer's huge solar sail gently propels the probe using the pressure of sunlight. The sail is the size of 4½ tennis pitches
Credit: NASA

Sunjammer, scheduled for launch in late 2014, is a NASA space probe that will carry the largest solar sail ever flown. The mission is designed to demonstrate the long-term potential of solar sails for spacecraft propulsion. In addition, Sunjammer will demonstrate the utility of sails to provide the earliest available warning of dangerous solar storms threatening Earth, and carry a payload of scientific instruments to study space weather.

Solar sails propel spacecraft using the pressure of light particles (photons) as sunlight shines upon them. The pressure exerted by light is small, and the propulsion is very gentle even on a large sail like Sunjammer’s, but it means the spacecraft does not rely on any onboard source of fuel. This makes the technology an extremely promising one for long-term space mission.

SWAN on Sunjammer is a really exciting implementation of MSSL’s highly miniaturised analysers

Members of the team behind Sunjammer, which includes UCL’s Mullard Space Science Laboratory, will be presenting their latest work at the International Symposium on Solar Sailing at the University of Strathclyde today (June 11). Members of the team are available for interview.

UCL will build the Solar Wind Analyser (SWAN) instrument that will be part of Sunjammer’s space weather payload. SWAN is a miniaturised ion spectrometer. Its primary aim is to demonstrate the technology for carrying out good measurements of solar wind using instrumentation on-board a spacecraft in the presence of the large sail. Such measurements are extremely valuable, particularly when available in real-time, for advanced space-weather warning systems, alerting satellite operators and utilities on Earth of potential hazards from geomagnetic storms caused by coronal mass ejections from the Sun.

“SWAN on Sunjammer is a really exciting implementation of MSSL’s highly miniaturised analysers,” says UCL’s Dhiren Kataria, the lead scientist on the SWAN instrument. “The team hope the mission in general and SWAN in particular delivers valuable data that would make a significant contribution to improving quality of life on Earth”.


Sunjammer is a NASA technology demonstration mission led by L’Garde, Inc. It will carry the largest solar sail ever launched, with an area of 1200 square metres, equivalent to 4 ½ tennis courts. SWAN, developed by UCL’s Mullard Space Science Laboratory is one of two UK-built scientific instruments which will be carried on board.

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Science contact

Dhiren Kataria (SWAN instrument lead scientist)
UCL Mullard Space Science Laboratory
07775 06 04 01

Page last modified on 07 jun 13 09:15