Chinese satellites meet European instruments in London for space mission pre-nuptials

The hardware inside a Chinese space satellite is currently
undergoing its final tests in London to make sure that it
can ‘talk’ with the European science instruments it will
be carrying, in advance of its mission launch in 2003.

37 scientists from the Chinese Academy of Sciences (CAS)
have spent the last three weeks in a converted seminar
room at Imperial College London carrying out the
‘pre-integration’ of European Space Agency (ESA)
instruments set to be carried aboard the CAS Double Star
mission next year.

Double Star follows in the footsteps of ESA’s Cluster
mission, which is studying the effects of the Sun on the
Earth’s magnetosphere — the ‘magnetic bubble’ that
protects the Earth from the worst effects of solar storms.

In a unique move, and to meet a tight mission schedule,
instrument-builders and researchers at Imperial proposed
that the pre-integration, the first meeting of European
instruments with the ‘brain’ of the Chinese spacecraft,
be done in Europe, the home of five of the instruments,
rather than in China, where the satellites are being
built.

The Chinese spacecraft systems arrived on 16 September
and were welcomed on the long, copper-covered analysis
table by the first test instrument, the Fluxgate
Magnetometer Instrument from Imperial.

As the Chinese hardware and the European instruments are
wired together, a computer simulates space conditions
outside the satellite and performs data and power system
tests to check whether the equipment will function
happily together.

In total over 50 European and Chinese space engineers
have been working on the pre-integration, which concludes
on 13 October.

“So far, all activities have been running very well and
even a few days ahead of schedule,” says Chris Carr,
Principal Investigator for the Magnetometer Instrument,
and research officer at Imperial. “All the European
teams are satisfied with the results of the tests and are
very impressed with the dedication and professionalism
of their Chinese counterparts. There’s been a great
spirit of cooperation, which we all hope bodes well for
the future,” he adds.

The five European scientific instruments (see Notes to
Editors) are very similar to the equivalent instruments
flown on Cluster, which launched in Summer 2000 — in
fact some of the European instruments are ‘spare’ units
from that mission.

The Chinese agency will launch two Double Star spacecraft,
one into an equatorial orbit, and the other polar. The
orbits are lower than Cluster and will keep Double Star
mainly inside the magnetosphere.

Double Star will conduct a number of scientific
investigations, most of which will augment measurements
coming from the four Cluster satellites. The Equatorial-
orbiting satellite will investigate the Earth’s huge
magnetic tail, the region where particles are accelerated
towards the polar regions by a process known as magnetic
re-connection.

Professor Peter Knight, Head of the Department of Physics,
which is hosting the pre-integration, welcomed the new
initiative by which outstanding space scientists in China
and at Imperial have been able to come together in this
exciting development.

“Space Physics is one of the major themes of the
department, with a number of missions looking at planetary
and comet systems as well as the interaction of the solar
wind with the earth. These missions involve years of
painstaking planning followed by keen anticipation of the
launch: we have great hopes for this innovative mission,”
he says.

In July 2001 the European Space Agency (ESA) and the
Chinese National Space Agency (CNSA) signed an agreement
to develop Double Star jointly. It was designed to
promote reciprocal cooperation between space scientists
in Europe and China, and also to pave the way for future
comprehensive collaboration between the two agencies.

Double Star also carries instruments from the Chinese
Centre for Space Science and Applied Research (CSSAR).

Notes to editors:

The European instruments to be pre-integrated are:

* FGM — Magnetometer (Imperial College London / IWF Graz,Austria)

* PEACE — Low energy electron measurements (MSSL, University College London)

* STAFF-DWP — AC Magnetic Field (Univ. Sheffield / CETP France)

* HIA — Hot ion measurements (CESR Toulouse, France)

* ASPOC — Spacecraft potential control (IWF Graz, Austria)