Saturday Night Science: Ultima Thule Encounter

New Horizon and 2014 MU69 (artists's conception)(Saturday Night Science usually appears on the first Saturday of the month.  I have moved up the January 2019 edition one week to discuss the New Horizons spacecraft fly-by of Kuiper belt object 2014 MU69, “Ultima Thule”, on New Year’s Day, January 1st, 2019.)

In January 2006 the New Horizons spacecraft was launched to explore Pluto and its moons and, if all went well, proceed onward to another object in the Kuiper Belt of the outer solar system, Pluto being one of the largest, closest, and best known members.  New Horizons was the first spacecraft launched from Earth directly on a solar system escape (interstellar) trajectory (the Pioneer and Voyager probes had earlier escaped the solar system, but only with the help of gravity assists from Jupiter and Saturn).  It was launched from Earth with such velocity (16.26 km/sec) that it passed the Moon’s orbit in just nine hours, a distance that took the Apollo missions three days to traverse.

In February 2007, New Horizons flew by Jupiter at a distance of 2.3 million km, using the planet’s gravity to increase its speed to 23 km/sec, thereby knocking three years off its transit time to Pluto.  While passing through the Jupiter system, it used its instruments to photograph the planet and its moons.  There were no further encounters with solar system objects until arrival at Pluto in 2015, and the spacecraft spent most of its time in hibernation, with most systems powered down to extend their lives, reduce staffing requirements for the support team on Earth, and free up the NASA Deep Space Network to support other missions.... [Read More]