Is Pioneer 10 in interstellar space

New Horizons passes 50 AU

A few days ago the time had come: NASA's New Horizons space probe exceeded the distance limit of 50 astronomical units. It is now more than 50 times as far from the sun as the earth and thus reaches regions of space in which only the Voyager and Pioneer probes were previously traveling. For the first time, she also pointed her camera at the position of Voyager 1.

NASA's New Horizons spacecraft, launched in January 2006, has provided unique views and data from the outer edge of our solar system: its flyby of Pluto in July 2015 revealed an amazingly dynamic world with clouds, mountains, snowfall and flowing glaciers. In 2019, the probe sent the first close-up images of the trans-Neptunian lump Arrokoth. From her control room in the Kuiper Belt she was also able to measure more precisely how dark space is far from the sun.

Milestone reached

The New Horizons probe has now reached a new milestone on its journey: on April 17, 2021, it passed a distance of 50 astronomical units. It is now 50 times farther away from the sun than our earth and thus reaches an area of ​​space in which there were only four other space probes before it: the Pioneer 10 and 11 probes, which have already been silent, as well as the two still active Voyager probes. However, because of its higher initial pace, New Horizons is the fastest spacecraft that has ever advanced these distances.

New Horizons is now about 7.5 billion kilometers away from us. At this distance, even the electromagnetic waves of radio communications need seven hours to travel. "It's hard to imagine such a vast distance," says Alice Bowman, operations manager for the mission team at the Johns Hopkins Applied Physics Laboratory. It takes 14 hours from the sending of a command to the confirmation of receipt by the probe.

View of Voyager 1

On the occasion of their milestone, New Horizons has pointed its camera at one of its neighbors: She took a picture of the star field in which Voyager 1 moves its orbit. It has been traveling in space since 1977 and in 2012 it was the first man-made spacecraft to cross the border into interstellar space. Today, Voyager 1 is around 151 astronomical units away from the sun - and therefore not directly visible in this image even to the sharp camera eyes of New Horizons.

"This is a poignant picture to me," said Alan Stern, New Horizons mission director at the Southwest Research Institute. “A flight through our entire solar system to explore Pluto and the Kuiper Belt so closely did not complete a mission before New Horizons.” Although the Voyager probes are a few decades ahead of their younger cousin, none of them is like that of the Kuiper Belt objects got close.

The trip goes on

The New Horizons mission is far from over: NASA will send a software upgrade to the probe this summer to bring its scientific instruments up to date. The batteries, powered by a nuclear mini-reactor, will provide enough power to keep the spacecraft alive until at least the 2030s.

Source: NASA

April 21, 2021

- Nadja Podbregar