Luna programme became the first probe to achieve a soft landing on another planetary body. It returned five black and white stereoscopic circular panoramas, which were the first close-up shots of the Lunar surface. "Luna 10" (March 1966) became the first artificial satellite of the Moon. "Luna 17" (November 1970) and "Luna 21" (January 1973) carried the Lunokhod vehicles, which roamed around on the Moon's terrain. Another major achievement of the Luna programme, with "Luna 16" (September 1970), "Luna 20" (February 1972) and "Luna 24" (August 1976), was the ability to collect samples of lunar soil and return them to Earth. The
Celestial navigation one of 57 other navigational stars to track celestial positioning. Latitude was measured in the past either by measuring the altitude of the Sun at noon (the "noon sight"), or by measuring the altitudes of any other celestial body when crossing the meridian (reaching its maximum altitude when due north or south), and frequently by measuring the altitude of Polaris, the north star (assuming it is sufficiently visible above the horizon, which it is not in the Southern Hemisphere). Polaris always stays within 1 degree of the celestial north pole. If a navigator measures the angle to Polaris and finds