posted 04-12-2010 06:24 PM               

Space Cover #52, Apollo XIII "at least something worked"

"...at least something worked" was the quote from astronaut Jim Lovell. The largest and heaviest man-made object to impact on the moon up to that time was the S-IVB/Instrument Unit of Apollo XIII, which was purposely smashed into the moon for scientific purposes.

The 5800 MPH crash of the 61.3 foot long third stage provided vital information for ultimately unraveling the mystery of the moon's origin.

The force of the impact was equivalent to 11 tons of TNT. The impact at 7:09 PM CST April 14, 1970, set off a 4-hour moonquake that was recorded by the seismometer erected in the Ocean of Storms by astronauts Charles Conrad and Alan Bean during Apollo XII.

The impact of the S-IVB/IU stage was about 230 miles west of the planned Apollo XIII landing site and 124 miles west of the Apollo XII landing site.

By comparing and correlating the impact data from the X-IVB/IU stage impact and that of the intentional crash of the ascent stage of the LEM 'Intrepid' during the Apollo XII mission scientists hoped to add to knowledge about the moon's composition and underground structures. The crashing of the 'Intrepid' at 3740 MPH caused shock waves which lasted nearly an hour. Normally the S-IVB/IU stage would have sped past the moon at a distance of about 2000 miles into an orbit around the sun.

The cover shown was produced by the founders of Solar Covers before it was formed.