When NASA's New Horizons spacecraft flew through the Kuiper Belt at a distance of approximately 705 million kilometers from Earth, an international team of astronomers used this far-reaching probe to conduct an unprecedented experiment: the first ever successful demonstration of deep-space interstellar navigation, Phys.org reports, writes UNN.
Details
The article describing the results has been accepted for publication in The Astronomical Journal. A preprint is available on arXiv.
As a proof of concept, the researchers took advantage of the spacecraft's unique vantage point as it moved through interstellar space to photograph two of our closest stellar neighbors - Proxima Centauri, which is 4.2 light-years from Earth, and Wolf 378, which is 7.86 light-years away.
From New Horizons' perspective, the two nearby stars changed their apparent positions in the sky, as seen by astronomers here on Earth, an effect known as stellar parallax.
Using the positions of the two stars and referencing a three-dimensional model of the solar environment, the team calculated the spacecraft's position relative to the nearby stars with an accuracy of about 6.6 million km.
Although this demonstration did not yield research-level results, the researchers note that such direct observation of large stellar parallaxes is extremely insightful.
According to Tod Lauer, an astronomer at NSF's NOIRLab in Tucson, Arizona, and the lead author of the paper, "we hoped that the simultaneous Earth/spacecraft imaging would instantly and visually make the concept of stellar parallaxes clear."
"It's one thing to know something, but it's quite another to say, 'Hey, look! It really works!'" he noted.
New Horizons is the fifth robotic spacecraft to leave Earth that will eventually reach interstellar space. Its primary mission was to study the dwarf planet Pluto and its largest moon Charon.
Addition
After a journey of nine and a half years and over 4.8 billion kilometers, it took stunning first images of these icy worlds and expanded our knowledge of their geology, composition, and tenuous atmospheres.
Now in its extended mission, New Horizons will continue to study the heliosphere and is expected to cross the "termination shock," the point that marks the boundary of interstellar space, in the next few years.