Will the Pioneer and Voyager probes ever leave the Milky Way? (Beginner)

What will eventually happen to the interplanetary probes Pioneer 10, Pioneer 11, Voyager 1 and Voyager 2, which are now on an escape trajectory from our solar system? Will they ever escape the Milky Way?

The probes will continue out of our solar system and will travel through space in the same direction in which they left the solar system. Pioneer 10 is heading toward Aldebaran and will get there in approximately two million years. Pioneer 11 is heading toward the constellation Aquila and will reach a star in four million years.

It is doubtful that the spacecraft will ever be able to leave the Milky Way, as they would have to attain a velocity of 1000 kilometers/second, and unless they get a huge, huge, huge velocity boost from something unexpected, they will probably end up being in the Milky Way's rotation forever. However, even if they could leave the Milky Way, it wouldn't be for millions and millions and millions of years, and we would long ago have lost communication with the Voyagers, with which we will theoretically be in contact until 2020.

Page last updated on June 25, 2015.

About the Author

Sarah Scoles

Sarah has a B.A. in astrophysics from Agnes Scott College, where she worked in the field of radio astronomy, and an MFA from Cornell, where she now teaches.

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