Live in orbit: Focused inspection unlikely

NASA is almost ready to clear shuttle Discovery's heat shield for atmospheric reentry, pending a now-standard inspection for micrometeoroid or orbital debris strikes done after departure from the International Space Station.

An ongoing review of launch imagery -- as well as data from orbital inspections of the shuttle's wings, nosecap and thermal tiles -- so far has rung no alarm bells or raised any significant concerns.

In fact, the Orbiter Project Office at NASA's Johnson Space Center in Houston is recommending that senior managers opt to forego a focused inspection on Saturday and press ahead with station assembly activities instead.

NASA's Debris Assessment Team, however, still is not finished reviewing about 300 high resolution photos of the thermal tiles on the underside of the orbiter. The photos were take by crewmates Clay Anderson and Yuri Malenchenko as shuttle skipper Pam Melroy guided Discovery through an orbital backflip just before final approach to the outpost.

NASA in the post-Columbia era of shuttle flight routinely sets aside time to do further inspection if a now-standard heat shield examination the day after launch turns up any evidence of significant damage. The "focused inspection" would come on Flight Day 5 -- Saturday.

But so far, Orbiter Project Office engineers examining 449 "regions of interest" have found none that would require an extra look -- a focused inspection.

Some 222 regions were deemed benign -- in other words, no damage at all. Another 118 regions had slight damage that is within the baseline of damage seen on previous missions. And another 109 regions had minor damage cleared by thermal protection system experts in the Orbiter Projects Office.

Again, though, the Damage Assessment Team -- the so-called DAT -- still is reviewing photos taken during the shuttle's reverse somersault.

A decision to forego a focused inspection would free up time to press ahead with what arguably is the hardest mission in the history of the shuttle or ISS programs. A final inspection of the shuttle's wings and nosecap now is done after the shuttle departs the station and prior to atmospheric reentry.

Senior mission managers likely will make a final call on a focused inspection in the next 48 hours.