New Horizons prepares for New Year's flyby by Ultima Thule

On October 3, NASA's New Horizons Space Shuttle briefly ignited the engine to determine the location and time of the New Year's flyby of the subject of the Kuiper Belt, nicknamed Ultima Thule.

A message from the spacecraft that he had completed the three-and-a-half-minute maneuver had reached the mission's operations at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, around 10:20 pm. EDT. The maneuver slightly altered the trajectory of the probe and increased its speed by 2.1 meters per second, or approximately 4.6 miles to the hour, allowing it to fly over Ultima (officially called 2014 MU69) to 1:33 am EST, January 1, 2019.

"Through this maneuver, we are in the middle of the pike and at the time of the most advanced exploration of worlds of history – to more than one billion kilometers from Pluto said lead mission researcher Alan Stern of the Southwest Research Institute. "It sounds almost like science fiction, but it's not … Go New Horizons!"

At 4.6 billion kilometers from Earth, Ultima Thule will be the most distant object ever visited by a spaceship. New Horizons itself was about 6.35 billion kilometers from its home country when it ran Wednesday's course correction maneuver (TCM), the highest heading correction ever made.

This was the first Ultima targeting maneuver using images taken by New Horizons himself to determine the position of the spacecraft relative to the subject of the Kuiper Belt. These "optical navigation" images – collected by Long Horizons' LORRI (long-range reconnaissance imager) – provide direct information on Ultima's position relative to New Horizons, and help the team determine the direction that will take the spacecraft.

The New Horizons team designed the TCM by determining the current trajectory of the spacecraft and its target and then calculating the maneuvers necessary to place the spacecraft at the desired "target point" of the overflight – at 3,200 kilometers (3,200 km) from Ultima to the nearest. approach.

"The recent navigation images have allowed us to confirm that Ultima is about 300 miles away. [500 kilometers] of its expected position, which is exceptionally good, "said Fred Pelletier, head of the New Horizons Navigation Team, KinetX Aerospace, Inc." We are delighted with the overview. "

Confirming that Ultima is in the planned location is an important and somewhat unique aspect of this overview. "Since we fly very fast and close to the surface of Ultima, about four times closer than Pluto's flyby in July 2015, the flyover time has to be very precise," said Derek Nelson , responsible for optical navigation at New Horizons, also from KinetX. "The images help determine the position and timing of the flyby, but we also need to trust the prior estimation of the position and speed of Ultima to ensure the success of the flyover. let us believe that Ultima is exactly where we expected, and the timing of the flyby will be accurate. "

The spacecraft is only 69 million kilometers (112 million kilometers) from Ultima and is approaching 32,256 kilometers (51,911 kilometers) per hour. Pelletier said the team will eventually have to guide the spacecraft into a "box" of about 75 km by 200 km (120 km by 320 km) and plan the flyby to about 140 seconds. "There is definitely more work to be done," he said. "But we take pictures of the farthest world ever explored, how cool is it?"

Explore further:
New Horizons makes its first Kuiper Belt flyover detection