Introduction
Science objectives of the 1 January 2019 flyby include characterizing the geology and morphology of 2014 MU69 (nicknamed Ultima Thule), and mapping the surface composition (by searching for ammonia, carbon monoxide, methane, and water ice). Searches will be conducted for orbiting moonlets, a coma, rings, and the surrounding environment. Additional objectives include:
2014 MU69 is the first object to be targeted for a flyby that was discovered after the spacecraft was launched. New Horizons is planned to come within 3,500 km (2,200 mi) of 2014 MU69, three times closer than the spacecraft's earlier encounter with Pluto. Images with a resolution of up to 30 m (98 ft) are expected.
The new mission began on October 22, 2015, when New Horizons carried out the first in a series of four initial targeting maneuvers designed to send it toward 2014 MU69. The maneuver, which started at approximately 19:50 UTC and used two of the spacecraft's small hydrazine-fueled thrusters, lasted approximately 16 minutes and changed the spacecraft's trajectory by about 10 meters per second (33 ft/s). The remaining three targeting maneuvers took place on October 25, October 28, and November 4, 2015.
New Horizons has been called "the fastest spacecraft ever launched" because it left Earth at 16.26 kilometers per second (58,536 km/h; 36,373 mph), faster than any other spacecraft to date. It is also the first spacecraft launched directly into a solar escape trajectory, which requires an approximate speed while near Earth of 16.5 km/s (59,000 km/h; 37,000 mph), plus additional delta-v to cover air and gravity drag, all to be provided by the launch vehicle.
However, it is not the fastest spacecraft to leave the Solar System. As of January 2018, this record is held by Voyager 1, traveling at 16.985 km/s (61,146 km/h; 37,994 mph) relative to the Sun. Voyager 1 attained greater hyperbolic excess velocity than New Horizons thanks to gravity assists by Jupiter and Saturn. When New Horizons reaches the distance of 100 AU, it will be travelling at about 13 km/s (47,000 km/h; 29,000 mph), around 4 km/s (14,000 km/h; 8,900 mph) slower than Voyager 1 at that distance. The Parker Solar Probe can also be measured as the fastest object, because of its orbital speed relative to the Sun at perihelion: 95.3 km/s (343,000 km/h; 213,000 mph).1 Because it remains in solar orbit, its specific orbital energy relative to the Sun is lower than New Horizons and other artificial objects escaping the Solar System.
Today the New Horizons spacecraft that studied Pluto has
passed a Kuiper Belt object, 2014 MU69, and information gathered will be sent
to Earth over the next 20 months.
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Kuiper Belt Encounter
Objectives
Science objectives of the 1 January 2019 flyby include characterizing the geology and morphology of 2014 MU69 (nicknamed Ultima Thule), and mapping the surface composition (by searching for ammonia, carbon monoxide, methane, and water ice). Searches will be conducted for orbiting moonlets, a coma, rings, and the surrounding environment. Additional objectives include:
- Mapping the surface geology to learn how it
formed and evolved
- Measuring the surface temperature
- Mapping the 3-D surface topography and surface
composition to learn how it is similar to and different from comets such
as 67P and dwarf planets such as Pluto
- Searching for any signs of activity, such as
a cloud-like coma
- Searching for, and studying, any satellites
or rings
- Measuring or constraining the mass
Targeting Maneuvers
2014 MU69 is the first object to be targeted for a flyby that was discovered after the spacecraft was launched. New Horizons is planned to come within 3,500 km (2,200 mi) of 2014 MU69, three times closer than the spacecraft's earlier encounter with Pluto. Images with a resolution of up to 30 m (98 ft) are expected.
The new mission began on October 22, 2015, when New Horizons carried out the first in a series of four initial targeting maneuvers designed to send it toward 2014 MU69. The maneuver, which started at approximately 19:50 UTC and used two of the spacecraft's small hydrazine-fueled thrusters, lasted approximately 16 minutes and changed the spacecraft's trajectory by about 10 meters per second (33 ft/s). The remaining three targeting maneuvers took place on October 25, October 28, and November 4, 2015.
Data Download
After the
encounter, preliminary, high-priority data will be sent to Earth on January 1
and 2, 2019. On January 9, New Horizons will return to a spin-stabilized
mode, to prepare to send the remainder of its data back to Earth. This download
is expected to take 20 months at the 1-2 kbps downlink data rate.
Speed
New Horizons has been called "the fastest spacecraft ever launched" because it left Earth at 16.26 kilometers per second (58,536 km/h; 36,373 mph), faster than any other spacecraft to date. It is also the first spacecraft launched directly into a solar escape trajectory, which requires an approximate speed while near Earth of 16.5 km/s (59,000 km/h; 37,000 mph), plus additional delta-v to cover air and gravity drag, all to be provided by the launch vehicle.
However, it is not the fastest spacecraft to leave the Solar System. As of January 2018, this record is held by Voyager 1, traveling at 16.985 km/s (61,146 km/h; 37,994 mph) relative to the Sun. Voyager 1 attained greater hyperbolic excess velocity than New Horizons thanks to gravity assists by Jupiter and Saturn. When New Horizons reaches the distance of 100 AU, it will be travelling at about 13 km/s (47,000 km/h; 29,000 mph), around 4 km/s (14,000 km/h; 8,900 mph) slower than Voyager 1 at that distance. The Parker Solar Probe can also be measured as the fastest object, because of its orbital speed relative to the Sun at perihelion: 95.3 km/s (343,000 km/h; 213,000 mph).1 Because it remains in solar orbit, its specific orbital energy relative to the Sun is lower than New Horizons and other artificial objects escaping the Solar System.
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