Voyager 1 and 2 are currently the two furthest human-made devices from Earth, and they’re not getting any closer. But where will they end up?
NASA, ESA, Roscosmos, the Indian Space Research Organisation, the Japanese Space Agency and China National Space Administration are pioneering scientific discovery in worlds far beyond ours.
Whether it’s plans to place an antenna on the dark side of the moon, land a probe on a speeding comet, send satellites into space or drive rovers around Mars, the various space agencies are continually pushing the envelope, searching for their next ‘man on the moon’ moment.
However, two of the longest-lasting missions, originally launched in the late 1970s, are still leading the way.
Voyager 1 and 2 left Earth in 1977, 16 days apart, initially looking through our solar system, before branching out into the most expansive investigation in human history.
It has gotten to a stage that, with each spacecraft billions of miles from Earth, only one thing can help them, and us, understand the mission: the Hubble Telescope.
Voyager 1, at 13bn miles away, and Voyager 2, at 10.5bn miles away, are essentially in an unexplored area of space, naturally.
Along the way, they are measuring the interstellar medium, the mysterious environment between stars. Hubble is on hand to provide what NASA calls the roadmap – measuring the material along the probes’ trajectories as they move through space.
“This is a great opportunity to compare data from in situ measurements of the space environment by the Voyager spacecraft and telescopic measurements by Hubble,” said study leader Seth Redfield.
“The Voyagers are sampling tiny regions as they plough through space at roughly 38,000mph. But we have no idea if these small areas are typical or rare.
“The Hubble observations give us a broader view because the telescope is looking along a longer and wider path. So Hubble gives context to what each Voyager is passing through.”
A preliminary analysis of the Hubble observations reveals a rich, complex interstellar ecology, containing multiple clouds of hydrogen laced with other elements. Hubble data, combined with the Voyagers, has also provided new insights into how our sun travels through interstellar space.
The predictions derived from both the probes as well as Hubble are incredibly far-reaching. In about 40,000 years – after Voyager 1 will no longer be operational and will not be able to gather new data – it will pass within 1.6 light years of the star Gliese 445 in the constellation Camelopardalis.
Its twin, Voyager 2, will pass 1.7 light years from the star Ross 248 at around the same time.
The next decade will see the Voyagers make measurements of interstellar material, magnetic fields and cosmic rays along their trajectories.
Hubble’s role is creating two lines of sight, showing the route each spacecraft will take, while still remaining operational.