1,868 articles
Rokot
Rokot (Рокот, Russian for "rumble") was a Russian expendable small-lift launch vehicle built from the retired SS-19 ICBM by Khrunichev, flying 32 orbital launches between 1994 and 2019.
Roman CGI
Roman CGI, the Coronagraph Instrument, is a NASA visible-light coronagraph on the Roman Space Telescope, built by JPL to demonstrate starlight suppression and exoplanet imaging, launched in 2026.
Romb
Romb is a Soviet satellite bus built by the Yuzhnoye design bureau for radar calibration satellites simulating warheads, flown under Cosmos designations from 1976 to 1995.
Ronald McNair
Ronald Erwin McNair was an American physicist and NASA astronaut, the second African American in space, who played saxophone aboard Challenger and died in its 1986 launch explosion.
ROSAT
ROSAT, the Roentgen Satellite, was a German, US, and UK X-ray astronomy satellite launched in 1990 that performed the first all-sky survey with an imaging X-ray telescope.
Roscosmos
Roscosmos (Роскосмос), also called the Russian Federal Space Agency, is the state corporation running Russia's civil space program, created in 1992 and reorganized in 2015.
Rosetta (spacecraft)
Rosetta was a European Space Agency spacecraft, launched in 2004, that in 2014 became the first mission to orbit comet 67P and deploy the Philae lander onto its surface.
Rossi X-ray Timing Explorer
The Rossi X-ray Timing Explorer (RXTE) was a NASA satellite launched in 1995 to study rapid time variability in cosmic X-ray sources; it operated for over 16 years until 2012.
Rotating detonation engine
A rotating detonation engine (RDE), in rocket form called a rotating detonation rocket engine, burns propellant with a supersonic detonation wave circling an annular chamber, promising higher efficiency.
Rover (space exploration)
A rover, or planetary rover, is a mobile vehicle that explores the surface of another celestial body, from the Soviet Lunokhod 1 of 1970 to NASA's Perseverance on Mars.
RP-1
RP-1, or Rocket Propellant 1, is a highly refined kerosene used with liquid oxygen in rockets such as the Atlas, Saturn V, and SpaceX Falcon 9.
RS-25
The RS-25, or Space Shuttle Main Engine, is a reusable liquid hydrogen and liquid oxygen rocket engine that powered the Space Shuttle from 1981 to 2011.
RS-68
The RS-68 is a liquid-fueled booster rocket engine developed by Rocketdyne, utilized for the first stage of the Delta IV launch vehicle, achieving over 650,000 pounds of thrust.
RTV-G-4 Bumper
The RTV-G-4 Bumper was the first large two-stage liquid-fueled rocket ever flown, an American project combining a captured German V-2 with a modified WAC Corporal upper stage.
Russian Orbital Segment
The Russian Orbital Segment, also called the Russian Segment, is the portion of the International Space Station operated by Russia's Roscosmos, begun with the Zarya module in 1998.
Ryusei (rocket)
Ryusei (流勢, ascending dragon) is a handmade gunpowder rocket flown for about 400 years at the Muku Shrine festival in Chichibu, Japan, to pray for a good harvest.
S-520
The S-520 is a Japanese single-stage sounding rocket developed by ISAS to replace the K-9M and K-10, first flown in January 1980 with a 300 km reach.
S-IVB
The S-IVB, also called Saturn S-IVB, was a Douglas rocket stage powered by one J-2 engine, serving as the Saturn IB's second stage and the Saturn V's third stage.
S. Somanath
Sreedhara Panicker Somanath is an Indian aerospace engineer who served as the tenth Chairman of ISRO from 2022 to 2025, overseeing the Chandrayaan-3 lunar landing.
SABRE (rocket engine)
SABRE (Synergetic Air-Breathing Rocket Engine) is a British hybrid rocket engine by Reaction Engines that breathes atmospheric air up to Mach 5 before switching to onboard oxygen.
Sakigake
Sakigake (さきがけ, "Pioneer") is a Japanese space probe built by ISAS and launched on January 8, 1985, to test the technologies for Japan's first deep-space mission, an encounter with Halley's Comet.
Sally Ride
Sally Ride was an American physicist and NASA astronaut who became the first American woman in space on Challenger in 1983 and served on both shuttle accident investigation boards.
Salyut 1 (Салют-1)
Salyut 1 (Салют-1), also designated DOS-1, was the world's first space station, a Soviet station launched uncrewed in 1971 and occupied for 23 days by the Soyuz 11 crew.
Salyut 6
Salyut 6 (Салют-6) was a Soviet space station launched in 1977, the first of a new Salyut generation with two docking ports enabling in-orbit resupply by Progress craft.
Salyut 7 (Салют-7)
Salyut 7 (Салют-7) was a Soviet space station launched in 1982, the last of the Salyut series, operated until 1991 and famous for the 1985 rescue mission.
Salyut programme
The Salyut program (Saliut) was a series of Soviet orbital space stations launched from 1971 to 1982, beginning with Salyut 1, the world's first space station.
Sample Analysis at Mars
Sample Analysis at Mars (SAM) is a suite of three chemistry instruments inside NASA's Curiosity rover, launched in 2011 and landed in Gale Crater in 2012.
SARAL
SARAL, also known as SARAL-AltiKa, is a joint Indo-French satellite launched in 2013 to measure ocean surface topography with the first Ka-band radar altimeter used for oceanography.
Sardinia Radio Telescope
The Sardinia Radio Telescope is a 64-meter fully steerable radio telescope near Cagliari, Sardinia, operated by INAF. Built from 2003 to 2010, it was inaugurated in 2013.
Satcom (satellite series)
Satcom, short for RCA SATellite COMmunications, was a family of geostationary communications satellites launched by RCA Americom from 1975 that distributed cable and broadcast television across the United States.