New horizons is about to reach a very scarce space, but do not expect NASA sin to rest on its considerable laurels.
On Saturday night (April 17), New Horizons will reach 50 astronomical units (AU) from the sun, a distance that has reached only four other operational sins in the history of space travel. (One AU is the average distance between the earth and the sun – about 150 million kilometers.)
The milestone is an opportunity to celebrate and appreciate the epic mission of New Horizons, which takes a closer look at humanity for the first time Pluto in July 2015 and followed it up with a flight from Arrokoth, a still distant world, three and a half years later.
Destination Pluto: NASA’s New Horizons mission in pictures
“When I stop with the daily hassle of planning and management, data analysis, budgets and all that, I just have to stop and think what we have achieved as a team, it’s really inspiring,” said Al Horizon, investigator from New Horizons, said. Stern told Space.com. “Sometimes I want to pinch myself.”
But there’s enough reason to look forward and backward, because New Horizons is far from over. Although it has been roaming through space for 15 years, sin remains in perfect health, Stern said, and he can still study the exotic environment for many years to come.
“We have power and fuel to go on in the late 2030s,” Stern said. He is based at the Southwest Research Institute in Boulder, Colorado. “So we are halfway through this mission in terms of what is possible from an engineering point of view.”
New Horizons is powered by a radioisotope thermoelectric generator (RTG), which produces electricity from the heat emitted by the radioactive decay of plutonium-238. RTGs also propelled most other NASA space probes, including the four that exceeded the 50 AU threshold before New Horizons did – Pioneer 10, Pioneer 11, Voyager 1 and Voyager 2.
Pioneer 10 and 11 stopped years ago, but the two Voyagers remain active today, more than 40 years after launch. Both explore the interstellar space: Voyager 1 is currently about 152 AU from Earth and Voyager 2 is almost 127 AU from us.
A very long journey
New Horizons’ journey has been going on for three decades and is full of twists and turns. Stern and his colleagues began developing a Pluto project in the late 1980s, but the $ 720 million mission was only officially approved in the early 2000s. (Read Stern and Planetary Scientist David Grinspoon’s 2018 book for more information on the tortuous history of the mission, “Chasing new horizons. “)
New Horizons was launched in January 2006, with the task of discharging Pluto for the first time. The distant dwarf planet has been mysterious since Clyde Tombaugh discovered it in 1930, and it was a vague spot in even the best photos of NASA. Hubble Space Telescope could monster.
New Horizons reached its highly anticipated flight distance on July 14, 2015 and zoomed in within 12,550 km of Pluto’s icy surface. The observations that sin made during this close encounter turned Pluto from that fuzzy spot into the right place – and a incredibly diverse and interesting place in addition, with high water icebergs, bizarre “leaf terrain” and a giant nitrogen-ice plain that forms one lobe of a now-famous “heart”.
After the flight, New Horizons continued to collect data about its surroundings, the ring of widespread, icy bodies outside the orbit of Neptune, known as the Kuiper Belt. The probe studied its local environment, observed a number of objects from the Kuiper Belt (KBOs) at a distance and on January 1, 2019, performed its second nearby flight, this time from a small KBO.
During the New Year’s encounter, New Horizons zoomed in on just 3,540 km from Arrokoth, which at the time was about 1.6 billion km further than Pluto’s orbit. The return of this close encounter, the center of the continuing mission of sin, was perhaps even more surprising than the Pluto data: the 22-kilometer-wide (36 km) Arrokoth looks like a flat, reddish space snowman with two distinct lobes.
New Horizons’ observations show this Arrokoth is a pristine and pristine object, a planetary building block left over from the solar system. And the two lobes were probably once different objects, which merged into a soft fusion, members of the mission team said.
“Both of our main goals appear to be scientific wonders – in both cases, we exceed our wildest expectations,” Stern said.
Related: New Horizons’ Arrokoth flyby in photos
Looking for flight target number three
The New Horizons team has already begun searching for another CBO along the path of the spacecraft, using photos captured by powerful instruments such as the Subaru Telescope in Hawaii. Stern emphasizes that a third fly is a long shot, given how thin the Kuiper belt is populated, but he and his colleagues are doing everything in their power to increase their chances.
Mission team members, JJ Kavelaars and Wes Patrick, for example, recently began applying machine learning techniques to the pursuit of CBOs to study, both from a distance and up close.
When the duo ‘reconsidered 2020 search data through their new software tools, not only did it work 100 times faster, but it found dozens of new KBOs that human searchers did not find in the search images!’ Stern het in a mission update last month. “We will use this important new tool again later this year, and next year and beyond.”
Even if no suitable flight target arrives, New Horizons will have plenty to do over the coming months and years. The investigation has so far looked at nearly 30 CBOs from afar, Stern said, and will study three more next month if all goes according to plan.
The May campaign will be another brick in the wall to build a statistically relevant collection of CBOs that we have studied in ways you can not do other than be in the Kuiper Belt, either by the short distance or because of the different angles at which we see things, ‘Stern said. “We’re building this database. It’s a legacy.”
New Horizons will do other work as well. It will continue to provide data on Uranus and Neptune, for example, and continues to characterize the Kuiper Belt environment, an empire that so far few investigators have explored. And, provided it stays healthy and NASA continues to approve mission expansions, New Horizons scientists will learn about the areas outside the Kuiper Belt, the outside of which is thought to be about 70 AU from the sun.
New Horizons will reach the limit in the late 2020s, Stern said. The spacecraft is likely to reach about 100 AU by the time the power runs out in the late 2030s, further confirming its place in the history of reconnaissance.
“We said we would build a spacecraft that could fly over the solar system and explore new worlds,” Stern said. “And we did it, and we still do it. But when I say the words – it sounds like science fiction, but it’s not.”
Mike Wall is the author of “Out there“(Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook.