NASA
Heavens-Above.com
Positions of Earth's distant emissaries.
Copyright © 2019
by Ralph F. Couey
Written content only
I revisit this subject from time to time, mainly because of my interest in deep space. I find it fascinating, not just that there are four probes either in or nearing interstellar space, but that long after we and our planet are gone, they will be drifting through the Milky Way Galaxy, the sole evidence that Earth and its creatures ever existed.
Voyagers 1 and 2, and Pioneers 10 and 11 were all launched in the 1970s, all part of the first real exploration of the planets of our solar system. The knowledge gained expanded by several orders of magnitude our understanding of the Sun's family, and as science often does, inspired several thousand new questions.
Once that mission was completed, all four were on trajectories that would take them all beyond the reach of the Sun's influence and into the unknown of interstellar space. The Pioneers are silent now, their power sources exhausted. The Voyagers are also expected to go dead sometime within the next year or so. But even though they will be inert, they will still be indisputable evidence to any intelligence which encounters them that there is, or was, other intelligent technological beings among the stars. The Pioneers have only their own existence to make that statement. But the Voyagers both carry gold plated disks, once called "records," along with instructions for their viewing that contain images and sounds of our planet and most important, images of us. In the perfect vacuum of space, they will be preserved for as long as the spacecraft themselves exist. For anyone who finds them, what we were, what we sounded like, how we lived, and where will become knowledge which will alter forever their view of the universe.
I thought if might be of interest to share the current locations of these spacecraft, where they are headed, and their ultimate fate.
Voyager 1: Currently 13.7 billion miles distant (about 20 light hours) it continues to speed along at 35,000 mph towards the constellation Ophiuchus. In about 16,700 years, it will pass within 1.7 light years from Proxima Centauri, the Sun's closest stellar neighbor, about 4.1 light years from here. Proxima Centauri is a low-mass red dwarf star that has at least one planet which orbits at about half the distance from Earth to the Sun. Proxima is one of three stars that make up the Alpha Centauri trio.
In 40,700 years, the craft will pass 1.7 light years from the star Gliese 445, another low-mass red dwarf. At this moment, Gliese 445 is 17.6 light years distant. But this star and ours are moving towards each other at a high velocity. So at that far-distant moment, 445's distance to the Sun will have been reduced to about 3.45 light years. At present, it is unknown whether Gliese 445 harbors any planets.
The craft will pass close by a star designated TYC 3135.52.1 in 302,700 years. Not much is known about this particular star, about 46 light years from Earth.
Voyager 1 will continue to sail along, and in 570,000 years will pass relatively close to two starts, GJ686 and GJ678. GJ686 is yet another low-mass red dwarf about 26.5 light years from Earth. It is considerably brighter than other red dwarfs, about 15 times more luminous than Proxima Centauri. Not much else is known.
GJ 678 is a brown dwarf, about 60 light years distant.
In 3.4 million years, V1 will pass 1.2 light years from a star designated Gaia DR22091429484365218432, about 520 light years from Earth.
Voyager 1's fate beyond that encounter is full of unknown variables. The spacecraft will pass through many gravitational influences, and might actually have a damaging encounter with any number of smaller bodies. Barring such a destructive end, Voyager will embark on an orbit around the center of the Milky Way, an orbit that will take some 26 million years to complete one revolution.
Voyager 2: This craft is currently 11.4 billion miles (17 light hours) from home, proceeding outward at just under 35,000 miles per hour. It is headed in the direction of the constellation Sagittarius. In 40,000 years, it will pass within 1.2 years of Ross 248. Ross 248 is a red dwarf currently at at distance of 10.3 light years from Earth. Like Gliese 445, Ross is also heading in our direction and in 80,000 years will briefly supercede Proxima Centauri as the closest star to Earth.
296,000 years from now, V2 will pass within 4.3 light years of Sirius. Sirius is a binary system 8.6 light years distant, consisting of Sirius, a white main sequence star twice as big as our Sun and is accompanied by a white dwarf, Sirius b. Sirius is the brightest star in our skies, and over the next 60,000 years will grow brighter as it, too, will be coming in our direction.
Beyond that, the expectation is that V2 will fall into a galactic orbit of 22.5 million years around the center of the galaxy.
Pioneer 10 is 9.6 billion miles distant and is headed towards Aldebaran, which it will pass closest about 2 million years from now. Pioneer 10 made a brief appearance in the movie Star Trek V when it was blown to flinders by a Klingon Bird of Prey.
Pioneer 11 is 7.8 billion miles distant and will pass Lambda Aquilae, the closest star in the constellation Aquila, in about 4 million years. Aquila is also home to one of the most famous structures, the Pillars of Creation.
Nobody knows how long the human race will exist. Certainly, the odds are against us, given climate change, natural disasters, and the certainty that Earth will once again be hit by a multiple-mile wide asteroid or comet at some time in the future, which will send humanity down the same path as the dinosaurs. Despite the dark nature of these possible futures, it is still a comfort that long after we are gone, long after our planet dies, there will be evidence in the presence of those four ancient spacecraft drifting through the galaxy that not only did humans exist, but that we survived long enough to reach for the stars.
From my perspective, there can be no more meaningful epitaph for humanity than to be remembered as a people with dreams. Big, galactic dreams.
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