Sputnjik 1 bio je prvi veštački satelit u Zemljinoj orbiti. Lansirao ga je Sovjetski Savez 4. oktobra 1957. godine sa kosmodroma u Bajkonuru (današnji Kazahstan). Satelit je bio loptastog oblika 58 santimetara u prečniku i težio je 83 kilograma. Imao je četiri spoljašnje antene koje su služile sa slanje i primanje radio signala, što je i bila njegova glavna uloga. Iako nije bio opremljen istrumentima za istraživanje, dao je važne podatke za razumevanje zemljine atmosfere. Trebalo mu je 98 minuta da obiđe Zemlju po eliptičnoj putanji. Nakon tri meseca rada Sputnjik je pao u Zemljinu atmosferu i izgoreo. Ovo lansiranje u potpunosti je zateklo SAD, koje su i same planirale da lansiraju veštački satelit. Ovim događajem počinje svemirska trka između SSSR-a i SAD-a koja će iznedriti mnoštvo misija sa ciljem daljeg istraživanja svemira.

Sputnik 1 was the first artificial satellite in Earth's orbit. It was launched by Soviet Union on 4th October 1957. from Baikonur Cosmodrome (today's Kazakhstan). The satellite was 58 cm in diameter polished metal sphere, and it weighted 83 kg. It had four external antennas that served as radio transmitter/receiver, which was its primary role. Although it wasn't equipped with scientific instruments, Sputnik gave some valuable data for further understanding of Earth's atmosphere. It took him 98 minutes to orbit the Earth on its ecliptic path. After three months of service, Sputnik fell into the Earth's atmosphere and burned up. Sputnik's launch stunned USA, who were planing to launch its own artificial satellite. This event marked start of the Space Race between USSR and USA, which will give many missions with purpose of further exploration of the Universe.