Context:

• NASA’s Voyager 2 has become the second human-made object in history to reach the edge of our solar system, after the spacecraft exited the protective bubble of particles and magnetic fields created by the Sun.

Details:

• Voyager 2 is the only probe ever to study Neptune and Uranus during planetary flybys.
• Voyager 2 is the only spacecraft to have visited all four gas giant planets — Jupiter, Saturn, Uranus and Neptune
• Its twin, Voyager 1, crossed this boundary in 2012, but Voyager 2 — launched 41 years ago — carries a working instrument that will provide first-of-its-kind observations of the nature of this gateway into interstellar space.
• Their observations complement data from NASA’s Interstellar Boundary Explorer (IBEX), a mission that is remotely sensing that boundary.

Interstellar space:

• In simple terms, it is a part of space that exists between stars
• Scientists define the beginning of interstellar space as the place where the sun’s constant flow of material and magnetic field stop affecting its surroundings. This place is called the heliopause. It marks the end of a region created by our sun that is called the heliosphere. The sun creates this heliosphere by sending a constant flow of particles and a magnetic field out into space at over 670,000 miles per hour. This stream is called the ‘solar wind.’