NewHorizons history

Interest in Pluto was again raised in 1978 when its largest moon Charon was discovered by the Voyager missions, showing that Charon was of significant size, influencing Pluto’s rotation so that both only showed the same sides to each other.

Launch windows to Pluto via Jupiter come approximately every 11 to 12 years, the 1979 window was not used since the Voyager 3 project was not realized.

After the fall of the Soviet Union, NASA entered a cooperation with Russia in 1994 to prospectively launch the PFF mission on a Proton rocket with the addition of a Russian-built Pluto lander.

Passing perihelion in 1999, Pluto began a long trek back out in its highly elliptical orbit that takes it through the coldest regions of the solar system leading to the substances in its atmosphere to freeze and precipitate to the surface.

The name was officially selected in February 2001 and a detailed mission proposal was submitted to NASA in April when the group of competing missions were narrowed down to two – New Horizons and POSSE, the Pluto and Outer Solar System Explorer.

The cancelation of PKE raised anger among scientists who had been counting on a mission launching in the 2003-07 window.

New Horizons was hit by bad news in July 2004 when it became clear that the Radioisotope Thermoelectric Generator was behind schedule.

It was found that 132524 APL had a close approach with New Horizons at 4:05 UTC on June 13, 2006 at a distance of 101,900 Kilometers.

The spacecraft passed the orbit of Saturn in June 2008 and made its annual checkout beginning in September before heading back into hibernation.

Hubble imagery showed a fifth satellite that was discovered in 2012 and named Styx, measuring less than ten Kilometers in size and orbiting at 38,000 Kilometers mean distance.

Data gathered by the instruments was downlinked in January 2013 during a short interruption of hibernation for checkouts.

On July 14, 2014, the sixth Trajectory Correction Maneuver was conducted by New Horizons.

The extended mission is expected to begin in 2017 with detailed planning for the KBO encounter.

After its flyby of Pluto, New Horizons flew by another Kuiper belt object, Arrokoth, on January 1, 2019.