October 23, 1995. Copyright, 1995, Graphic News. All rights reserved

EUROPE'S BRAND NEW EYE ON COSMIC HEAT AND DUST
By Nicholas Booth, Science Editor

LONDON, October 23, Graphic News- Imagine a world where the darkest objects appear brightest and the sky is bright night or day. Welcome to the universe as seen at infrared wavelengths Ð beyond the reach of the human eye Ð where astronomers effectively measure the heat signature of objects they are observing. And now, thanks to a European satellite due for launch on November 8, a giant leap forward will be taken to unravel the enduring mysteries of this most curious area of the cosmos.

The Infrared Space Observatory (ISO) will spend 18 months high above the Earth where it will reveal the secrets of how planets, stars Ð and possibly life itself Ð are formed. After twelve years work, an expenditure of more than £250 million and unparalleled technical problems, ISO has been one of the most challenging missions ever developed by the European Space Agency. To detect very faint heat signatures of distant stars and galaxies, the telescope itself has to be kept very cool. The motion of atoms within the detectors would swamp any signal emanating from the edge of space. 

So ISO resembles a giant dewar flask in which its electronics and optics are cooled by liquid helium to within a fraction of the coldest temperature of all Ð absolute zero. During manufacture, ISO's cryogenically-cooled tank developed problems and had to be repeatedly opened after being sealed. But although the mission is effectively two years late, the fact that it will be launched aboard a European Ariane vehicle from ESA's ÔspaceportÕ in French Guiana, shows the maturity of Europe's space programme. More than 35 companies around the continent worked to develop what has been described as the most challenging mission the agency has ever attempted.

In a month's time, ISO will be joined in orbit by an ESA-built solar observatory and next year by a flotilla of spacecraft called Cluster, which will monitor the Earth's interaction with the Sun. Their launch comes at a time when the British government had wanted a 25 per cent cutback in ESA's science budget, but which was overturned at last week's meeting of ministers from the agency's member states. ESA's scientific projects will be funded at a constant rate of £267.5 million for the next five years.

So the stage is set for the best ever views of the infrared universe from ISO and new data on the mysteries of the swirling clouds of dust and gas in which stars and planets form. These dust and gas clouds accumulate between existing stars and as they swirls, pressures and temperatures become so great that they undergoes thermonuclear ignition. The problem is that at visible light these stellar nurseries cannot be seen: at present it is not known how planets form out of this material. Clues as to why should be revealed to ISO in the infrared.

Source: European Space Agency