I got a chance to ask NASA science chief Ed Weiler today about two pressing issues. First, is the servicing mission to the Hubble Space Telescope, scheduled for 12 May, threatened at all by the messy collision of two satellites on 10 Feburary, as some had worried?

Weiler is confident that everything is on track. He points to the fact that the current Space Shuttle mission, delayed yet again today for other reasons, had been cleared for launch. The Hubble servicing will take place at a higher elevation — closer to the space junk — but not enough to cause problems, Weiler says. “I don’t see any threat to the May 12 mission right now.”

With regards to the Orbiting Carbon Observatory, which crashed into the ocean after an unsuccessful launch, Weiler says no decisions have yet been made. The “knee-jerk” reaction, he says, is to rebuild immediately, using spare parts and existing decade-old designs. But Weiler says there’s value also in taking an approach at the other end of the spectrum: Manage the best one can with existing carbon measurements, and take the time to build a state-of-the-art carbon observatory. NASA could also opt for something in the middle.

But, I asked him, wouldn’t the $400 million in the stimulus package, given to NASA specifically for Earth science, be spent perfectly on rebuilding the $278 million OCO? Weiler says only part of an OCO price tag could be satisfied with stimulus money, which has to be spent within 18 months. An OCO II would take longer to build, in other words. “And there are plenty of other things to spend that [stimulus] money on, especially in Earth science,” he says. He says Earth science division director Michael Frielich is consulting with senior scientists in the community on the approach to take and will make a decision in the coming month.