Luna 1 becomes the first spacecraft to reach the vicinity of the Moon.

Luna 1, also known as Mechta, E-1 No.4 and First Lunar Rover, was the first spacecraft to reach the vicinity of Earth's Moon, the first spacecraft to leave Earth's orbit, and the first to be placed in heliocentric orbit. Intended as a Moon impactor, Luna 1 was launched as part of the Soviet Luna programme in 1959.

A spacecraft is a vehicle that is designed to fly and operate in outer space. Spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, planetary exploration, and transportation of humans and cargo. All spacecraft except single-stage-to-orbit vehicles cannot get into space on their own, and require a launch vehicle.

The Moon is Earth's only natural satellite. It orbits around Earth at an average distance of 384,399 kilometres (238,854 mi); about 30 times Earth's diameter. Its orbital period and its rotation period are synchronized at 29.5 days by Earth's gravity pulling on the Moon. This makes the Moon tidally locked to Earth, always facing it with the same side. The Moon's gravitational pull produces tidal forces on Earth, which are the main driver of Earth's tides.

January 4 is the fourth day of the year in the Gregorian calendar; 361 days remain until the end of the year.