re: Astronomers observe occultation of next New Horizons flyby target

A primitive solar system object that’s more than four billion miles (6.5 billion kilometers) away passed in front of a distant star as seen from Earth. Just before midnight Eastern Time Sunday (12:50 a.m. local time July 17), several telescopes deployed by the New Horizons team in a remote part of Argentina were in precisely the right place at the right time to catch its fleeting shadow — an event that’s known as an occultation.

In a matter of seconds, NASA’s New Horizons team captured new data on its elusive target, an ancient Kuiper Belt object known as 2014 MU69. Weary but excited team members succeeded in detecting the spacecraft’s next destination, in what’s being called the most ambitious and challenging ground occultation observation campaign in history.

“So far we have five confirmed occultations,” said Marc Buie of the Southwest Research Institute (SwRI) in Boulder, Colorado, holding up five fingers as New Horizons scientists pored over the exhilarating initial data. Buie led a team of more than 60 observers who battled high winds and cold to set up a “picket fence” of 24 mobile telescopes in a remote region of Chubut and Santa Cruz, Argentina. Their goal: to spot the shadow of the mysterious Kuiper Belt object (KBO) where New Horizons will fly by on New Year’s Day 2019 – to better understand its size, shape, orbit and the environment around it. Before these observations, only the Hubble Space Telescope successfully detected MU69, and even it had not been able to determine MU69’s size or shape.