What is the closest star to Earth?
The closest star to Earth is the Sun. After the Sun, the nearest star is Proxima Centauri, about 4.24 light-years away, part of the Alpha Centauri system.
The Sun is about 150 million kilometers away, close enough that its light reaches us in about 8 minutes. Proxima Centauri is about 40 trillion kilometers away. Its light takes over four years to reach us.
Proxima Centauri is a small red dwarf, too faint to see without a telescope. It orbits a pair of brighter stars, Alpha Centauri A and B, about 4.37 light-years away. Together they are visible as a single bright point from the Southern Hemisphere.
A planet next door
Proxima Centauri has at least one planet, Proxima b, discovered in 2016. It orbits in the zone where liquid water might exist, although the star's powerful flares could make conditions harsh for life.
Alpha Centauri is the target of a proposed project called Breakthrough Starshot, which aims to send tiny probes pushed by powerful lasers at a fraction of the speed of light, reaching it in about 20 years.
Did You Know?
Even the fastest spacecraft launched so far would take thousands of years to reach Proxima Centauri.