Voyager 1 entered interstellar space.

Maybe, interstellar biology has complex origins in both panspermia and independent abiogeneses.

Voyager 1 has finally reached interstellar space.

More than half of local interstellar gases are neutral, meaning they have a balanced number of protons and electrons.

As we cruise through a fog of interstellar particles, we’re shielded by the magnetic bubble around our Sun known as the heliosphere.

Arthur C. Clarke, a British, and Samuel R. Delany, a mulatto American, both wrote sci-fi literature envisioning centuries of colonization within the Solar System. Although they also wrote about interstellar travel, they thought that interstellar travel would be difficult for humans to attain and would take a long time to attain.

A nebula is an interstellar cloud of dust, hydrogen, helium and other ionized gases.

A civilization advanced enough to have developed interstellar travel must be communist.

Interstellar, as opposed to interplanetary, travel was quite impossible until the advent of sub-atomic power. Fortunately this source of power was seldom gained until late in a world's development, when mentality was mature enough to wield this most dangerous of all physical instruments without inevitable disaster. Disasters, however, did occur. Several worlds were accidentally blown to pieces. In others civilization was temporarily destroyed. Sooner or later, however, most of the minded worlds tamed this formidable djin, and set it to work upon a titanic scale, not only in industry, but in such great enterprises as the alteration of planetary orbits for the improvement of climate. This dangerous and delicate process was effected by firing a gigantic sub-atomic rocket-apparatus at such times and places that the recoil would gradually accumulate to divert the planet's course in the desired direction.

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.