Voyager traveling beyond the final frontier:
A few years ago Voyager 1 entered the final frontier, that place where the solar wind becomes denser and hotter and pressure from gas between stars causes it to slow - the Termination Shock.Now that Voyager 2 has reached its edge of the solar system, just under 7 billion miles from Earth, it has confirmed what astrophysicists had believed - the conflict between the solar wind and the interstellar wind has made that part of the solar system slightly squashed.
To envision the Sun's presence in the Milky Way galaxy, think of a ship plowing through the ocean, being tossed by currents. As the ship sails ahead, a bow shock spreads around the vessel.
The area under the Sun's influence, stretching well beyond the planets and forming what's called the heliosphere, is like a ship. The outer edges of the heliosphere are gently buffeted by interstellar wind, the gas and dust between the stars. As the Sun orbits the center of the Milky Way galaxy, the heliosphere moves as well, creating a bow shock ahead of it in interstellar space.
What does it all mean? Well, the termination shock is a lot more complex than anyone had thought and there's more to discover. Nothing ever moves quickly in space and it could be years before the next big event but, for now, Voyager 2's journey into the vast unknown is pretty exciting.
More after the link, including a video animation to help explain more.