"James Oberg" wrote in message
.. .
The best guess now is that the object departing columbia on flight day 2
was
a hunk out of the left RCC panel 8, maybe half a foot across or more.

Suppose it had shown up on an exterior PLB camera view, flashing off near
the horizon.

Would it have looked really different from 'ordinary' debris, different
enough to be a recognizable symptom of something worth worrying about?

I doubt that its optical characteristics would have helped distinguish it
from ordinary debris, but perhaps spotting it on video would have prompted a
more timely search for it in USSTRATCOM's radar logs. Did NASA have
precudures in place that would have quickly brought the existence of a piece
of co-orbital debris to the attention of the people who were concerned about
the foam strike?

Analysis of its orbital elements would have revealed its ballistic
coefficient, which fit well with the densest elements of the shuttle's TPS -
the RCC and densest tiles.

Regardless of its physical properties, the object appears to have been
unique in that no previous shuttle mission that did not conduct an EVA or
satellite deployment resulted in the cataloguing of unaccounted debris.
Quoting from my web page on the FD 2 object:

"Most of the catalogued debris were items confirmed lost by astronauts
during EVAs: a screwdriver on STS 51I, a wire carrier and a socket on STS
88, a pad on STS 102.
Two pieces of debris were catalogued subsequent to the EVA of STS 106. I am
unaware of any reports from NASA linking them to the EVA. Their orbital
elements are not sufficiently accurate to confirm that separation occurred
during the EVA.

Two pieces catalogued from STS 51, appear to be from the anomalous
deployment of the ACTS satellite, which resulted in the shedding of debris
into orbit.

2003-003B may well be unique; however, it was only found after it had
decayed, as a result of an unprecedented post-flight search of archived
radar observation logs, motivated by the loss of Columbia and her crew.

Would a similar retrospective of previous shuttle missions have turned up
other unaccounted debris? What would have been their physical properties? If
the archival data exists, it might be worth the effort to find out just how
unique 2003-003B may have been."

If so, does this imply future shuttle flights should keep a better eye
outside?

I believe so.

Ted Molczan