Did you know that 2 crewless spacecraft launched by NASA in 1977, Voyager 1 and 2, are now in Interstellar Space? It’s true. Quite an amazing achievement when you think about it.
Now, what exactly is Interstellar Space? Where does it begin?
Ever consider that? It’s not so simple when you think about it because the Solar System is quite complex.
First you have the Sun. Then the Planets and Asteroid Belt. Out beyond Neptune is the Kuiper Belt where Pluto and many other objects exist. Then as you go way beyond that you’ll finally arrive at the Oort Cloud where some comets originate from.
So, where does Interstellar Space begin?
The Sun is the most powerful structure in our Solar System. It creates a massive magnetic field and affects the flow of particles. This combination is known as the Solar Wind, and the effects of this “Wind” are felt out beyond the Kuiper Belt. The point at which the Solar Wind and Interstellar Wind are in balance is known as the Heliopause. So beyond this boundary is what scientists consider Interstellar Space, even though the Oort Cloud exists farther out.
The shape of the Heliopause fluctuates, but it’s approximately 11 billion miles from the Sun. Yes, you heard me right, 11 billion.
Voyager 1 crossed it in 2012, and Voyager 2 in 2018.
Humanity now has spacecraft in Interstellar Space. And the 2 little craft are still sending data back to Earth, even after all these years.
I’d say that’s an achievement to be proud of.