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SOFIA to work with New Horizons during upcoming Pluto encounter

David Dickinson, Correspondent
Jun 25, 2015, 18:23 UTC

Sen—NASA’s high-flying infrared observatory is Down Under this week to observe the southern sky, and to make a unique observation ahead of New Horizons' historic encounter with Pluto and its moons next month.

The aircraft is an unusual airborne observatory known as SOFIA, or the Stratospheric Observatory For Infrared Astronomy. SOFIA began observations in 2010, and consists of a 2.5-meter telescope mounted aboard a modified Boeing 747SP wide-body aircraft.

In addition to numerous southern sky targets, astronomers hope to catch a rare occultation of a +12th magnitude star by the planet Pluto on June 29. Observers will utilize the High Speed Imaging Photometer for Occultations (HIPO) and the Focal Plane Imager (FPI) to record the brief, seconds-long event.

“SOFIA’s 2013 deployment to New Zealand and the resulting observations were of great scientific value,” SOFIA program manager Eddie Zavala said in a recent press release. “Our research staff and guest investigators have been looking forward to building on that success with our return to the Southern Hemisphere this month.”

This occultation gives astronomers a chance to measure the atmosphere of Pluto and its composition just before New Horizons' July 14 encounter. New Horizons will also pass through the shadows of Pluto and Charon and witness two radio occultations—think of it as the most distant solar eclipses ever recorded—for comparison.

And you never know what other types of serendipitous discoveries might result. A similar occultation of a background star by Uranus was witnessed by SOFIA’s predecessor the Kuiper Airborne Observatory in 1977. This event revealed the ring system of Uranus, as the star's light dimmed two times more than expected as the planet passed in front of it.


The passage of New Horizons through the Pluto-Charon system on July 14. Image credit NASA/JHU-APL