Gliese 581 d is an extrasolar planet orbiting the red dwarf star Gliese 581. Image File history File links Current_event_marker. ... An extrasolar planet, or exoplanet, is a planet beyond the Solar System. ... The following are lists of stars with confirmed extrasolar planets. ... Gliese 581 is an M2. ... This article or section does not adequately cite its references or sources. ... Libra (IPA: , Latin: , symbol , Unicode ) is a constellation of the zodiac. ... Equatorial Coordinates Right ascension (abbrev. ... In astronomy, declination (abbrev. ... In astronomy, stellar classification is a classification of stars based initially on photospheric temperature and its associated spectral characteristics, and subsequently refined in terms of other characteristics. ... The elements of an orbit are the parameters needed to specify that orbit uniquely, given a model of two ideal masses obeying the Newtonian laws of motion and the inverse-square law of gravitational attraction. ... In geometry, the semi-major axis (also semimajor axis) a applies to ellipses and hyperbolas. ... The astronomical unit (AU or au or a. ... In astrodynamics, under standard assumptions any orbit must be of conic section shape. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... Look up day in Wiktionary, the free dictionary. ... Inclination in general is the angle between a reference plane and another plane or axis of direction. ... In astrodynamics, the longitude of the periapsis (symbolized ) of an orbiting body is the longitude (measured from the point of the vernal equinox) of periapsis (closest approach to the central body). ... A diagram of Keplerian orbital elements. ... A diagram of Keplerian orbital elements. ... The Julian day or Julian day number (JDN) is the (integer) number of days that have elapsed since Monday, January 1, 4713 BC in the proleptic Julian calendar [1]. That day is counted as Julian day zero. ... Unsolved problems in physics: What causes anything to have mass? The U.S. National Prototype Kilogram, which currently serves as the primary standard for measuring mass in the U.S. Mass is the property of a physical object that quantifies the amount of matter and energy it is equivalent to. ... Adjectives: Terrestrial, Terran, Telluric, Tellurian, Earthly Atmosphere Surface pressure: 101. ... Circle illustration In classical geometry, a radius (plural: radii) of a circle or sphere is any line segment from its center to its boundary. ... Adjectives: Jovian Atmosphere Surface pressure: 20–200 kPa[4] (cloud layer) Composition: ~86% H2 ~13% Helium 0. ... In physics, density is mass m per unit volume V. For the common case of a homogeneous substance, it is expressed as: where, in SI units: ρ (rho) is the density of the substance, measured in kg·m-3 m is the mass of the substance, measured in kg V is... The U.S. National Prototype Kilogram, which currently serves as the primary standard for measuring mass in the U.S. It was assigned to the United States in 1889 and is periodically recertified and traceable to the primary international standard, The Kilogram, held at the Bureau International des Poids et... The cubic meter (symbol m³) is the SI derived unit of volume. ... Fig. ... The Kelvin scale is a thermodynamic (absolute) temperature scale where absolute zero—the lowest possible temperature where nothing could be colder and no heat energy remains in a substance—is defined as zero kelvin (0 K). ... Any planet is an extremely faint light source compared to its parent star. ... An extrasolar planet, or exoplanet, is a planet beyond the Solar System. ... Red Dwarf is a British science fiction comedy franchise, the primary form of which comprises eight series of a post-watershed television sitcom that ran on BBC2 between 1988 and 1999, and which has achieved a global cult following. ... STAR is an acronym for: Organizations Society for Telescopy, Astronomy, and Radio, a non-profit New Jersey astronomy club. ... Gliese 581 is an M2. ...

Discovery

The planet was discovered by the team of Stephane Udry of the Geneva Observatory in Switzerland using the HARP instrument on the European Southern Observatory 3.6 meter telescope in La Sille, Chile. Udry's team employed the radial velocity, technique, in which the size and mass of a planet are determined based on the small perturbations it induces in its parent star’s orbit via gravity. The European Southern Observatory (ESO) is an international astronomical organisation, composed and supported by ten countries from the European Union plus Switzerland. ... Radial velocity is the velocity of an object in the direction of the line of sight. ...

References

• Major Discovery: New Planet Could Harbor Water and Life

See also

• Gliese 581 b
• Gliese 581 c