Washington: The launch-day mishap to Columbia space shuttle from debris peeling away from a booster fuel tank may have been much worse than thought at first, as new assessment reveals that the size of the insulation that fell on its wing at supersonic speed was as big as a brick.

High-tech cameras detected a block of insulation as hard as a brick and the size of a carry-on suitcase peeling away from the fuel tank and pulverising as it crashed into the thermal tiles on the orbiter's left wing, 80 seconds after Columbia hurtled away from Kennedy Space Centre in Florida on January 16.

"Although that may in fact wind up being the cause – it may certainly be the leading candidate right now – we have to go through all the evidence and rule things out very methodically to arrive at the cause," William F Readdy, director of Spaceflight at the National Aeronautics and Space Administration (NASA), told the 'Washington Times'.

NASA tested the premise using the "somewhat conservative assumption" that the 20-by- 16-by-6-inch block of foam insulation weighing 2.67 pounds gave the left wing a blow at supersonic speed near the main landing gear door, then shattered into dust, the daily reported.

PTI