NASA’s space probe, Voyager I – launched nearly 35 years ago – may be about to become the first human-made object to leave the solar system after flybys of Jupiter and Saturn. Space is quite big, and scientists use a unit of measurement called an astronomical unit – the general distance between the Earth and the sun – to measure distances within our solar system.
Voyager I is now 121 astronomical units from Cape Canaveral, Florida - where it launched in September of 1977 – and it is silently screaming away from us at roughly 17 kilometers per second (a speedy 38,000 miles per hour). Scientists are basing this speculation on data from Voyager I that shows it has left the heliosphere, a bubble of solar winds emitted by our sun.
Once Voyager makes it past that region of space, it will be headed into interstellar space, which so far has only been the realm of imagination for humankind. Although Voyager I isn’t headed towards a particular destination, the next object in space, the star Proxima Centauri, is 4.2421 light years from Earth.
These animations show NASA's Voyager spacecraft encounters with Jupiter, Saturn, Uranus and Neptune and the start of the continued mission into interstellar space.
What can we learned from the unmanned exploration of space? Will humans someday reach distant stars in person?
Arik Posner, program scientist for the Heliophysics Division of NASA’s Science Mission Directorate