Mullard Space Science Laboratory

P R E S S  R E L E A S E

11 November 2004
REF: SWIFT2004-3


On Wednesday 17 November 2004 an unmanned Delta II rocket will be launched from Cape Canaveral, USA. The rocket will be carrying NASA's Swift Gamma-Ray Observatory and placing it in orbit 400 miles above the Earth. It is hoped that Swift will answer some of the biggest questions astronomers have faced for decades.

Swift's mission is to observe gamma-ray burst (GRBs). GRBs are the most powerful explosions the Universe has seen since the Big Bang. They occur approximately once per day and are brief, but intense, flashes of gamma radiation. They come from all different regions of the sky and last anywhere from a few milliseconds to a few hundred seconds. So far scientists do not know what causes them. Do they signal the birth of a black hole in a massive stellar explosion? Are they the product of the collision of two neutron stars? Or is it some other exotic phenomenon that causes these bursts?

On board the Swift observatory are three instruments; the Burst Alert Telescope (BAT), X-Ray Telescope (XRT) and the UltraViolet/Optical Telescope (UVOT). The BAT will detect and locate the position of any gamma ray burst that occurs within its wide field of view. Then, using this information, the spacecraft will rapidly slew to allow the other two narrow field telescopes (XRT and UVOT) to also observe that part of the sky and study the afterglow from the GRB in their respective wavelengths. Within seconds of detecting a burst, Swift will relay a burst's location to ground stations, allowing both ground-based and space-based telescopes the opportunity to observe the burst's afterglow.

The UltraViolet/Optical Telescope (UVOT) was designed, built and tested by a team of scientists and engineers at University College London's Mullard Space Science Laboratory (MSSL) in Holmbury St. Mary, lead by Laboratory Director Prof. Keith Mason. Prof. Mason says "This is one of the most ambitious instruments MSSL has built to date, in terms of the scientific and technical requirements and the delivery schedule. Once again, the team of staff at MSSL have pulled together and we have delivered a first-class space instrument that we and Britain can be proud of."

With Swift, scientists will now have a tool dedicated to solving the gamma-ray burst mystery. Its three instruments will give scientists the ability to scrutinize gamma-ray bursts like never before.


Notes to Editors:

1. The Mullard Space Science Laboratory, situated at Holmbury St Mary, is the Department of Space and Climate Physics of University College London. About 120 people work on space science and space engineering. The Laboratory plays key roles in many missions of space exploration. Over 250 instruments have been launched into space to date, to study astrophysics, solar and stellar physics, plasma and planetary physics and climate physics.

2. UVOT is a 30cm diameter modified Ritchey-Chrétien telescope with an f/2.0 primary beam that is re-imaged to f/13 by the secondary. The sky image is recorded on a photon counting, intensified CCD detector, which operates at the ambient temperature of the instrument. The detector covers a field of view of 17-arcmin square with 0.5 arcsec pixels and is sensitive between 170nm and 650nm. A filter wheel provides broadband energy discrimination via filters, together with two grisms for low-resolution spectroscopy and a 4x-image expander for near-diffraction limited imaging. An Instrument Control Unit (ICU) configures the instrument, provides thermal control and interfaces with the spacecraft, while a Data Processing Unit (DPU) intelligently handles the science data.

3. Images of the Swift spacecraft and instruments are available via the internet from:

4. As part of MSSL's Public Outreach Programme, a group of local school children have been invited to MSSL for a presentation by MSSL scientists where they can learn about the Swift mission, gamma-ray bursts, and watch the Swift launch via a live link-up with NASA TV.

C O N T A C T S:

Mullard Space Science Laboratory
University College London
Holmbury St. Mary, Dorking
Surrey, RH5 6NT

MSSL switchboard: 01483 204100
MSSL website:

Professor Keith Mason - UVOT Principle Investigator
Mary Carter - Technical
Alex Blustin - Science
Tracey Poole - Outreach