This artist's concept depicts NASA's Voyager 1 spacecraft entering interstellar space, or the space between stars. Interstellar space is dominated by the plasma, or ionized gas, that was ejected by the death of nearby giant stars millions of years ago. The environment inside our solar bubble is dominated by the plasma exhausted by our sun, known as the solar wind.
The interstellar plasma is shown with an orange glow similar to the color seen in visible-light images from NASA's Hubble Space Telescope that show stars in the Orion nebula traveling through interstellar space.
Illustration credit: NASA/JPL-Caltech
Note: For more information, see NASA Voyager Statement About Solar Wind Models and Sun Sends More 'Tsunami Waves' to Voyager 1.