Palmdale to Pluto – and Beyond

When the New Horizon spacecraft reaches the fringes of the solar system and flies by Pluto on July 14, it will have a connection to the greater Valley billions of miles away. The craft will use data collected by the stratospheric observatory for infrared astronomy, better known as SOFIA, which is operated by NASA in Palmdale. SOFIA, which carries a 17-ton telescope on a modified 747 jumbo jet, observed Pluto on June 29 as it came between a faint, unnamed star and Earth in a celestial event called an occultation. That occurrence allowed its 100-inch reflecting mirror to measure the density and structure of Pluto’s atmosphere for 90 seconds. Dana Backman, director of outreach for the SOFIA program, said the brief observation gives scientists a look at Pluto and any surface activity that may be happening in its atmosphere. “This is the context for the details that (New Horizon) will be getting,” Backman said. While the SOFIA program employs between 200 and 300 people in Palmdale, the observation took place while the 747 was flying at least 40,000 feet out of Christchurch, New Zealand. The jet flies across the globe to target its telescope and the altitude ensures water vapor won’t disrupt its infrared receptors. SOFIA previously observed Pluto in 2011 when it flew 1,800 miles out over the Pacific Ocean. Pluto was discovered in 1930 and was considered the ninth planet of the solar system until it was reclassified as a dwarf planet in 2006. Still, it has an atmosphere despite a mean surface temperature of -229 degrees Celsius. Pluto will be the last major body in the solar system to receive a flyby from a spacecraft when the New Horizon visits. “It is the last box to be checked in robotic exploration,” Backman said. — Mark R. Madler