Out of all the exoplanets found by Kepler, this distant world – located 300 light-years from Earth – is most similar to Earth in size and estimated temperature.

A black hole in the center of the M87 galaxy in the constellation Virgo, which is 50 million light-years away, has been calculated to have a mass equal to that of 3 billion Suns!

The planet Sakura is 4.7 light-years away.

The parsec is equal to about 3.3 light-years.

Trappist-1 is located just 39 light-years away from Earth.

Typically, a space station serviced a locale at least several light-years radially.

The size of a galaxy may be as little as a thousand light-years across or as much as a million light-years across.

The spiral galaxy closest to our Milky Way galaxy is Andromeda. Andromeda is over 2 million light-years away. Its central bulge and spiral arms are tilted toward us at a 15 degree angle.

The researchers caution, however that communication with these alien civilizations could be difficult, as the average distance to them would be about 17,000 light-years.

Sirius is a binary star system and is about 8.6 light-years distant from our sun.