Proposal for extended New Horizons mission submitted to NASA
An extended mission proposal featuring a close flyby of a Kuiper Belt Object (KBO) along with distant observations of 20 more KBOs and further study of the environment of the outer Solar System has been submitted to NASA by the New Horizons team.
Dubbed the Kuiper Extended Mission or KEM, the proposal seeks additional funding to fly by the small KBO 2014 MU69, an objected estimated to be 13 to 25 miles (21 to 40 kilometers) wide and a billion miles (1.6 billion kilometers) beyond Pluto.
The target KBO was found in a special search on behalf of the mission by scientists using the Hubble Space Telescope in 2014.

Since launching in January 2006, New Horizons has traveled over 3 billion miles (5 billion kilometers). It will continue another billion miles before flying past 2014 MU69. Image Credit: NASA
The proposed flyby, in which the spacecraft would approach MU69 from a distance of 1,900 miles (3,000 kilometers), four times closer than it passed by Pluto, will take place January 1, 2019.
MU69 is 1,000 times more massive than Comet 67P/Churyumov-Gerasimenko, currently being orbited by the Rosetta spacecraft, but is 500,000 times less massive than Pluto.
“This places it in a key intermediate size regime to better understand planetary accretion,” Principal Investigator Alan Stern wrote in the proposal. “Given its four-plus-billion-year existence in cold storage so far from the Sun, MU69 will be the most pristine object ever visited by any space mission.”
All seven of New Horizons’ science instruments will be used during the flyby of MU69, enabling spectroscopy, imaging, and compositional mapping better than that done at Pluto.
The proposal calls for high-resolution mapping of MU69’s surface, color mapping, studies of surface properties, and searches for moons, rings, and an atmosphere.
To conserve fuel, the mission team conducted engine burns last fall, putting the spacecraft on target for the KBO flyby.
If NASA approves the mission, flyby operations would start in late September 2018 and continue through the first week of January 2019. The data collected would then be sent back to Earth over a period of 20 months.
While MU69 will be the only close flyby, the proposal calls for distant observations of about 20 other KBOs between 2016 and 2020 with the goal of searching for satellites and rings, determining the objects’ shapes, and understanding their surface properties.
Among these 20 objects are three dwarf planets, Haumea, Makemake, and Eris, along with several candidate dwarf planets such as Ixion and Quaoar, which are believed to be large enough to be spherical.
The spacecraft will also study gas, dust, and plasma as far as 50 astronomical units (AU) from the Sun. One AU is equal to the average Earth-Sun distance, or 93 million miles (150 million kilometers). Astrophysical observations will be conducted during 2020 and 2021.
According to NASA guidelines, the KEM proposal will be peer-reviewed, with a response expected around June or July of this year. If the mission is approved, planning and observations for it will start this fall.
Stern said mission team members are optimistic about the proposal being approved.

Laurel Kornfeld
Laurel Kornfeld is an amateur astronomer and freelance writer from Highland Park, NJ, who enjoys writing about astronomy and planetary science. She studied journalism at Douglass College, Rutgers University, and earned a Graduate Certificate of Science from Swinburne University’s Astronomy Online program. Her writings have been published online in The Atlantic, Astronomy magazine’s guest blog section, the UK Space Conference, the 2009 IAU General Assembly newspaper, The Space Reporter, and newsletters of various astronomy clubs. She is a member of the Cranford, NJ-based Amateur Astronomers, Inc. Especially interested in the outer solar system, Laurel gave a brief presentation at the 2008 Great Planet Debate held at the Johns Hopkins University Applied Physics Lab in Laurel, MD.