It’s Official NASA’s Voyager 2 Spacecraft Leaves the Solar System
Ladies and Gentlemen, it is official. NASA’s Voyager 2 probe, which left our planet in 1977 has become the second manmade object in the history to successfully leave our solar system.
The news that Voyager had exited our solar system was revealed at the American Geophysical Union (AGU) meeting in Washington.
The historic news was revealed by chief scientist on the mission, Prof Edward Stone who said that both Voyager 1 and 2 have successfully made it into interstellar space. He added that Voyager’s 2 date of departure from our solar system was November 5, 2018.
For the second time in history, a human-made object has reached the space between the stars. Now slightly more than 11 billion miles (18 bil. km) from Earth, @NASAVoyager 2 has now left the Sun's protective bubble & is flying in interstellar space: https://t.co/zRnhiaJqGS #AGU18 pic.twitter.com/Zzncki4GKB
— NASA (@NASA) December 10, 2018
So, how do scientists know the spacecraft has left the solar system?
Experts say that the most compelling evidence comes from Voyager’s 2 onboard Plasma Science Experiment, the PLS.
The space surrounding Voyager 2, was until recently, filled predominantly with plasma originating from our sun.
This outflow engulfs our solar system in a massive cosmic bubble which is called the heliosphere.
After visiting Jupiter, Saturn, Uranus and Neptune, @NASAVoyager 2 has left the Sun's protective bubble and is now flying in the interstellar space between the stars. Learn more about this incredible mission as the encore to the Grand Tour begins: https://t.co/nvffnCO3jm #AGU18 pic.twitter.com/T6kOWrxYzH
— NASA (@NASA) December 10, 2018
Using the electrical current of the plasma, the PLS detects speed, density, temperature as well as pressure and flux of the solar wind.
On November 5, scientists monitoring the PLS noticed a steep decline in the speed of the solar wind.
Since that day, the PLS has not observed traces of solar wind flow in the environment through which Voyager 2 is currently traveling.
This means that the spacecraft has left the heliosphere, and hence our solar system.
“Working on Voyager makes me feel like an explorer because everything we’re seeing is new,” said John Richardson, principal investigator for the PLS instrument and a principal research scientist at the Massachusetts Institute of Technology in Cambridge.
“Even though Voyager 1 crossed the heliopause in 2012, it did so at a different place and a different time, and without the PLS data. So we’re still seeing things that no one has seen before.”
But more evidence that the spacecraft has left our solar system has been found in other instruments on board the probe.
Mission scientists have explained that they have seen evidence from three other instruments, the cosmic ray subsystem, the low energy charged particle instrument and the magnetometer. All of these factors combined are consistent with the conclusion that NASA’s spacecraft has finally crossed the heliopause.
“Voyager has a very special place for us in our heliophysics fleet,” said Nicola Fox, director of the Heliophysics Division at NASA Headquarters.
“Our studies start at the Sun and extend out to everything the solar wind touches. To have the Voyagers sending back information about the edge of the Sun’s influence gives us an unprecedented glimpse of truly uncharted territory.”