Kosmos 96

Did You Know?

• Kosmos 96 was the third and last spacecraft prepared for a Venus encounter during the 1965 launch window.
• The 3MV-4 No.6 spacecraft was originally built for a Mars mission scheduled for late 1964 but was repurposed after missing its launch window.
• Two other spacecraft from the same repurposing were launched as Venera 2 and Venera 3.

Launch

The spacecraft was launched on a Molniya 8K78 carrier rocket from Baikonur Cosmodrome's Site 31/6 at 03:22 GMT on 23 November 1965. During the late phase of third-stage flight, a fuel line rupture caused one combustion chamber to explode, sending the rocket into an uncontrolled tumble. The Blok-L fourth stage consequently failed to ignite. The spacecraft was deployed into a low Earth orbit with a perigee of 227 km, an apogee of 310 km, an inclination of 51.9°, and an orbital period of 89.8 minutes. It was designated Kosmos 96 to conceal the failure; had it departed Earth orbit, it would have been named Venera 4. The spacecraft was destroyed upon re-entering Earth's atmosphere on 9 December 1965.

The Great Lakes fireball and Kecksburg incident

Some speculation connects the re-entry of Kosmos 96 to a fireball seen over southwestern Ontario and at least eight US states from Michigan to New York at 21:43 GMT on 9 December 1965. Analysis of photographs and sightings suggested the fireball's path through the atmosphere was too steep for a spacecraft re-entering from Earth orbit and was more likely a meteor from the asteroid belt, probably ending over western Lake Erie. U.S. Air Force tracking data indicated Kosmos 96's orbit decayed earlier than 21:43 GMT that day. Unconfirmed reports claim the fireball landed near Kecksburg, Pennsylvania, at 21:46 EST, though estimating impact points from eyewitness accounts is notoriously inaccurate. Uncertainties in orbital information and re-entry coordinates make it difficult to definitively determine whether the fireball was Kosmos 96.