List of Astronomy Acronyms - R

R

• RAPTOR – Rapid Telescopes for Optical Response project
• RA – (astrophysics terminology) Right Ascension
• RAFGL – See AFGL.
• RAMBO – (celestial object) An association of brown dwarfs or white dwarfs form a dark cluster.
• RAS – (organization) Royal Astronomical Society
• RASC – (organization) Royal Astronomical Society of Canada
• RASS – (observing program/catalog) ROSAT All-Sky Survey, used as both a name for a survey with ROSAT and the catalogs produced from the survey
• RC – (celestial object) Red Clump, a type of metal-rich red giant star
  • also RCG – Red Clump Giant
• RC – (catalog) Reference Catalogue, a catalog of nearby galaxies
  • RC2 – Reference Catalogue, 2nd edition
  • RC3 – Reference Catalogue, 3rd edition
• RC – (organization/telescope) Ritchey Chretien, a manufacturer of amateur and professional telescope equipment; also the telescopes themselves
• RCB – (celestial object) R Coronae Borealis, a class of eruptive variable stars named after R Coronae Borealis, the archetype for the class
• RDI – (astrophysics terminology) Radiation Driven Implosion
• RECONS – (organization) Research Consortium on Nearby Stars, a survey of nearby stars
• RGB – (celestial object) Red-Giant Branch, a star that is evolving from a main-sequence star into a red giant
• RGO – (organization) Royal Greenwich Observatory
• RLOF – (astrophysics terminology) Roche Lobe Overflow, the result of when an object in a binary system is larger than its roche lobe (i.e. when an object in a binary system expands to a radius where tidal forces become stronger than gravitational forces)
• RLQ – (celestial object) Radio Loud Quasar, a quasar that produces strong radio emission
• RNGC – (catalog) Revised New General Catalog
• RORF – (astrophysics terminology) Radio/Optical Reference Frame, an inertial reference frame based on extragalactic radio sources
• ROSAT – (telescope) ROentgen SATellite, an X-ray space telescope
• ROTSE – (observing program/telescope) Robotic Optical Transient Search Experiment, an observing program for detecting the optical counterparts of gamma ray bursts; also the telescopes used in this program
• RQQ – (celestial object) Radio Quiet Quasar a quasar that produces weak radio emission
• RRAT – (celestial object) Rotating Radio Transient, a population of rotating neutron stars that produce periodic bursts of emission that are separated by intervals of minutes or hours
• RRL – (celestial object) RR Lyrae, a class of pulsating variable stars named after RR Lyrae, the archetype of the class
  • also RR
• RSA – (catalog) Revised Shapley Ames, a catalog of nearby galaxies
• RSA – (organization) Russian Space Agency
• RSAA – (organization) Research School of Astronomy and Astrophysics, part of the Institute of Advanced Studies at the Australian National University
• RSG – (celestial object) Red Super Giant
• RSN – (celestial object) Radio SuperNova
• RTG – (instrumentation) Radioisotope Thermoelectric Generator, a type of power generator used in spacecraft that travel far from the Sun
• RV – (astrophysics terminology) Radial Velocity, the velocity along the line of sight
• RX – (catalog) ROSAT X-ray, a catalog of sources detected by ROSAT
• RXTE – (telescope) Rossi X-Ray Timing Explorer, a space telescope designed to observe variability in X-ray emission