ESA Science & Technology - Launch of the first element of International Space Station on 20 November

Unlike free-flying satellites, which are generally optimised for a particular scientific objective, the ISS will provide a re-usable platform for observations or experiments which permits servicing or replacement of components, sample return or even construction of larger telescopes which cannot be launched conventionally.

ESA has completed the selection of experiments for the first early flight opportunity on external platforms, which will commence before completion of the construction of ISS. This will contain:

• A package of 3 solar telescopes to monitor the changes in absolute solar power output from the complete solar disk over a range of wavelengths, of vital importance to the study of the Earth's atmosphere as well as stellar astronomy.

• A telescope to map the polarisation of the sky at millimetre wavelengths to help distinguish between background sources and the cosmic microwave background signal from the moment the universe first became transparent shortly after the Big Bang.

In addition, a number of space environment sensors measure the radiation, gas, plasma and cosmic dust influx to the Space Station, will be incorporated on the Technology Exposure Facility.

Launch of the European Columbus Orbital Facility (COF) in the new millennium, which will house additional attached payload sites, will provide a further opportunity for astronomy and space science. Plans are already under way to design a 10m X-ray telescope, known as XEUS, for construction at the space station and release as a free-flying observatory.

The Space Science community is waiting for further reports on the launch, which heralds the start of a new era in scientific observations from space.