- Historical event:
- 13 June 1983
- The Pioneer 10 probe carries the famous gilded plaque with human figures and a pictorial message for possible extraterrestrial beings. This plaque was made in collaboration with the famous Carl Sagan.
On this day in 1983, the first man-made object left the Solar System. It was the Pioneer 10 space probe, launched back in 1972 (11 years earlier).
It left the Solar System when it crossed the orbit of Neptune on this day (at that time, Neptune was the farthest known planet from the Sun).
Of course, this is just one of the possible ways of defining the boundaries of the Solar System and interstellar space.
In the history of space exploration, only four space probes have left the Solar System so far. Those were Pioneer 10, Pioneer 11, Voyager 1, and Voyager 2.
All four were launched during the 1970s. It was only in 2006, that the new, fifth, probe intended to leave the Solar System was launched. Its name is New Horizons.
The Pioneer 10 probe carries the famous gilded plaque with human figures and a pictorial message for possible extraterrestrial beings.
This so-called Pioneer plaque was also placed on Pioneer 11 and was made in collaboration with the famous Carl Sagan. It displays the nude figures of a human male and female and the position of the Earth relative to the other planets of the Solar System. Also, it shows the relative position of the Sun to the surrounding pulsars.
Today, Pioneer 10 is about 16 billion kilometers from the Sun, traveling at the speed of about 43,300 kilometers per hour, in the general direction of the star Aldebaran in constellation of Taurus.
It would take the probe more than two million years to reach it, assuming that Aldebaran has no movement relative to the probe.