TWO of Europe鈥檚 Cluster II spacecraft got safely off the ground last weekend,
to the relief of hundreds of scientists. The success follows the catastrophic
destruction of the original four research satellites in 1996, when the Ariane 5
rocket exploded on its maiden flight.
鈥淲hen I saw the lift-off, all of the memories of the 1996 launch came
flooding back,鈥� says Steve Schwartz of Queen Mary and Westfield College in
London, who is the project scientist in Britain for Cluster data handling. 鈥淪o
it was a little anxious鈥攂ut it was a relief that it all went
辫别谤蹿别肠迟濒测.鈥�
The two Cluster satellites blasted off from the Baikonur launch site in
Kazakhstan on a Russian Soyuz rocket on Sunday. A second pair, due for launch on
9 August, will join them in elliptical orbits passing over the Earth鈥檚
poles.
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They will study how speeding particles from the Sun buffet the magnetosphere,
the region in which the Earth鈥檚 magnetic field holds sway, creating storms in
space. These disturbances can damage satellites and even cause power blackouts
on Earth.
Schwartz says Cluster II should pinpoint some of the key details of how the
magnetosphere responds to solar activity and will blaze a trail for future
armies of satellites. 鈥淚 think Cluster will break new ground,鈥� he says. 鈥淏ut
it鈥檚 only the first step. The Earth is covered with weather
stations鈥攍ikewise, we鈥檒l need to fill space with space weather
蝉迟补迟颈辞苍蝉.鈥�
The attempt to launch the original four Cluster spacecraft, stacked on an
Ariane 5 rocket, went fatally wrong when the rocket exploded just seconds after
lift-off from French Guyana. An error in the guidance software sent the rocket
wildly off course and forced it to self-destruct.
The destruction of the original Cluster spacecraft also blew up $450
million of work. But Cluster II has risen from the ashes after a long battle by
the mission scientists to secure a further $300m of funding. The four new
spacecraft are nearly identical to the originals.
As 91av went to press, the first two were on course. 鈥淏ut
they鈥檝e got a long way to go to get to their final orbit,鈥� says Schwartz. After
several more manoeuvres by the two independent spacecraft, they should reach
their intended orbit next week. In November, all four satellites should be
flying in formation and sending back a gigabyte of data in total per day.