And in the midst of this color, between the two evening stars, a third white star burst into being and shot up the sky, leaving a short straight contrail. This was the usual dramatic appearance that aerobraking continuous shuttles made as they burned into the upper atmosphere, almost as visible by day as by night. It only took about a minute for them to cross the sky from one horizon to the other, slow brilliant shooting stars.

But this time, when it was still high in the west, it got fainter and fainter, until it was no more than a faint star. And was gone.

Du Martheray’s observation room was crowded, and many exclaimed at this unprecedented sight, even though they had been warned. When it was completely gone Zeyk asked Sax to explain it for those of them who had not heard the full story. The orbital insertion window for aerobraking shuttles was narrow, Sax told them, just as it had been for the Ares back in the beginning. There was very little room for error. So Sax’s technical group in Da Vinci Crater had equipped a rocket with a payload of metal bits— like a keg of scrap iron, he said— and they had shot it off a few hours before. The payload had exploded in the approaching shuttle’s MOI path just a few minutes before its arrival, casting the metal fragments in a band that was wide horizontally but narrow vertically. Orbital insertions were completely computer-controlled, of course, and so when the shuttle’s radar had identified the patch of debris, the AI navigating the shuttle had had very few options. Diving below the debris would have put the shuttle through thicker atmosphere, very likely burning it up; going through the debris would risk holing the heat shield, likewise burning it up. Shikata ga nai, then; given the risk levels programmed into it, the AI had had to abort the aerobraking run by flying above the debris, thus skipping back out of the atmosphere. Which meant the shuttle was still moving outward in the solar system at very near its top speed of 40,000 kilometers per hour.

“Do they have any way to slow down except aerobraking?” Zeyk asked Sax.

“Not really. That’s why they aerobrake.”

“So the shuttle is doomed?”

“Not necessarily. They can use another planet as a gravity handle to swing around, and come back here, or go back to Earth.”

“So they’re on their way to Jupiter?”

“Well, Jupiter is on the other side of the solar system right now.”

Zeyk was grinning. “They’re on their way to Saturn?”

“They may be able to pass very close to several asteroids sequentially,” Sax was saying, “and redirect their crash— their course.”

Zeyk laughed, and though Sax went on about course correction strategies, too many other people were talking for anyone to be able to hear him.

• • •