– OUT OF THIS WORLD –
• Here is the life story of several brave satellites who sacrificed their lives to further the horizon of science.
• NASA’s Magellan spacecraft, launched from space shuttle Atlantis in 1989, was the first deep space probe launched by a space shuttle. Named after the Portuguese explorer, it was assembled using spare parts from prior missions. It was sent on a mission to rendezvous with Venus, which it reached on August 10, 1990.
• Beginning on Sept. 15, 1990, the spacecraft began returning high-quality radar images of the surface of Venus that showed evidence of volcanism, tectonic movement, turbulent winds, miles of lava channels, and many pancake-shaped domes.
• Magellan completed its first 243-day cycle (the time it took for Venus to rotate once under Magellan’s orbit) of radar mapping on May 15, 1991, providing the first clear views of 83.7% of the surface.
• The spacecraft returned 1,200 gigabits of data. Keep in mind that at this point in history, NASA’s total data for all planetary missions combined equaled only 900 gigabits. Magellan was expected to last only a single cycle, yet it persisted through a second and third cycle, which mapped 98% of the surface and showed that 85% of Venus is covered with volcanic flows. Magellan accomplished three more cycles which ended in 1994, far beyond the expected lifespan of the space probe. Only then did it begin to malfunction.
• NASA controllers commanded the spacecraft to drop into the Venusian atmosphere. Contact was lost on Oct. 13, 1994, as it continued to gather data while it plunged to its death. Magellan burned up in the atmosphere following one of NASA’s most successful deep space missions.
CASSINI-HUYGENS
• The combined Cassini–Huygens spacecraft was launched on October 15, 1997. Cassini, named after the French/Italian astronomer who discovered four of Saturn’s 82 moons, was NASA’s probe to Saturn. Piggybacking along was the European Space Agency’s Huygen, named for the Dutch astronomer who discovered Saturn’s largest moon, Titan. Huygen was designed to land on Titan.
• Huygens was released from Cassini on December 25, 2004. Plunging into Titan’s atmosphere, the probe survived the 2 hour 27 minute descent and touched down on Titan’s frozen surface. It transmitted data for another 72 minutes before contact was lost. Huygens was the first landing on any celestial body beyond Mars. Data transmitted included 350 pictures that showed a shoreline with erosion features and a river delta. Huygens’ remains may still be on the surface of Titan.
• Cassini was the first space probe to orbit Saturn. Cassini entered Saturn’s orbit on June 30, 2004. The intrepid satellite was originally slated for a four year mission, yet it remained in service until 2017. Cassini conducted nearly 300 orbits of Saturn, took more than 453,000 pictures, did many fly-bys of Jupiter’s moons, studied Titan, discovered six more moons including two that may harbor life, examined Saturn’s atmosphere, revealed much about the make-up of Saturn’s rings, and sent back 635 gigabytes of data.
• In 2017 as Cassini neared the end of its life, NASA programmed it to fly in ever-closer orbit to the surface of Saturn in a “Grand Finale” before it was instructed to commit suicide by plunging into the surface, transmitting data as it did so. Scientists feared that otherwise, a deceased and out-of-control Cassini might end up crash landing into one of Saturn’s many moons, contaminating it with bacteria that might have survived the voyage from Earth.
