Then a crack like a thunderbolt echoed across the dome. One of the huge lower boughs on a two-hundred-year-old oak tree split open close to the thick trunk, and the bough crashed down. Leaves swirled upwards like a flock of startled butterflies. The whole majestic tree sagged, with further fissures opening along the length of the trunk. It twisted as it started to fall into its neighbour. The elegant little tree house platform which the band had been playing on barely a minute ago splintered and snapped apart. The last glimpse Justine had of the trees was a couple of red squirrels scampering out of the toppled giants.

The malmetal safety bunker doors contracted behind her, and for a moment she was enveloped within an oasis of calm. It was a bizarre image, everyone still dressed in their best party clothes, breathing heavily with dishevelled hair and anxious faces. Director Trachtenberg was standing beside her, looking round wild-eyed.

'You okay? he asked.

She nodded, not quite trusting her voice.

Another of the gravity waves swept through the station. Once again Justine felt her weight lessen. Her u-shadow accessed the station's net, and she pulled out the sensor images of the sky above. The Raid's DF spheres were still accelerating across the star system to their new positions. She checked that the Silverbird, was unaffected by the weird gravity waves which the DF sphere's were throwing off. The starship's smartcore told her it was maintaining position just above the dusty lava field which served as the station's landing area.

'I've just conferred with our alien colleges, Director Trachtenberg announced. He smiled wryly. 'Those that talk to us, anyway. And we all agree the gravity shifts are beyond anything the safety systems were designed for. With regret I am ordering an immediate evacuation.

Several people groaned in dismay.

'You can't, Graffal Ehasz complained. 'This is what we're here for. Dear Ozzie, man, the data this event is spewing out. What we can learn is unprecedented! We can't just crawl away because of some safety restriction imposed by a committee back in the Commonwealth.