Aquarius is an equatorial constellation of the zodiac, between Capricornus and Pisces. Its name is Latin for "water-carrier" or "cup-carrier", and its old astronomical symbol is (♒︎), a representation of water. Aquarius is one of the oldest of the recognized constellations along the zodiac. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations. It is found in a region often called the Sea due to its profusion of constellations with watery associations such as Cetus the whale, Pisces the fish, and Eridanus the river.
HD 28185 b is an extrasolar planet 128 light-years away from Earth in the constellation of Eridanus. The planet was discovered orbiting the Sun-like star HD 28185 in April 2001 as a part of the CORALIE survey for southern extrasolar planets, and its existence was independently confirmed by the Magellan Planet Search Survey in 2008. HD 28185 b orbits its sun in a circular orbit that is at the inner edge of its star's habitable zone.
HD 102195 is an orange-hued star in the zodiac constellation of Virgo with a confirmed exoplanet companion. With an apparent visual magnitude of 8.07, the star is too faint to be seen with the naked eye. The distance to HD 102195 can be estimated from its annual parallax shift of 34.06 mas, yielding a separation of 95.8 light years. It is moving further away from the Earth with a heliocentric radial velocity of 1.85 km/s. This is a high proper motion star and a possible member of the η Cha stellar kinematic group.
A super-Earth is a type of exoplanet with a mass higher than Earth's, but substantially below those of the Solar System's ice giants, Uranus and Neptune, which are 14.5 and 17 times Earth's, respectively. The term "super-Earth" refers only to the mass of the planet, and so does not imply anything about the surface conditions or habitability. The alternative term "gas dwarfs" may be more accurate for those at the higher end of the mass scale, although "mini-Neptunes" is a more common term.
HD 164922 b is an exoplanet orbiting the star HD 164922 about 72 light-years from Earth in the constellation Hercules. Its inclination is not known, and its true mass may be significantly greater than the radial velocity lower limit of 0.36 Jupiter masses. The planet also has a low eccentricity, unlike most other long period extrasolar planets – 0.05 – about the same as Jupiter and Saturn in the Solar System. The exoplanet was found by using the radial velocity method, from radial-velocity measurements via observation of Doppler shifts in the spectrum of the planet's parent star.
HD 125612 is a binary star system with three exoplanetary companions in the equatorial constellation of Virgo. It is too dim to be visible to the naked eye, having an apparent visual magnitude of 8.31. The system is located at a distance of 188 light years from the Sun based on parallax measurements, but it is drifting closer with a radial velocity of −18 km/s.
HD 154345 is a star in the northern constellation of Hercules. With an apparent visual magnitude of +6.76 it is a challenge to view with the naked eye, but using binoculars it is an easy target. The distance to this star is 59.6 light years based on parallax, but it is drifting closer with a radial velocity of −47 km/s. At least one exoplanet is orbiting this star.
HD 2039 is a yellow dwarf or yellow subgiant star in the constellation Phoenix. The star is not visible to the naked eye, and lies 280 light years away from the Sun. HD 2039 is a relatively stable star, and an exoplanet at least three times the mass of the planet Jupiter has been discovered in its orbit; this exoplanet, known as HD 2039 b, was the 100th exoplanet to be discovered.
HD 231701 is a yellow-white hued star in the northern constellation of Sagitta, near the southern constellation border with Aquila. With an apparent visual magnitude of 8.97, it is too dim to be viewed with the naked eye, but can be seen with powerful binoculars or a small telescope. Parallax measurements provide a distance estimate of approximately 356 light years from the Sun, but it is drifting closer with a radial velocity of −63 km/s. It is predicted to come as close as 189.5 light-years in 1.345 million years.
HD 192699 b is an exoplanet located approximately 214 light-years away in the constellation of Aquila, orbiting the star HD 192699. This planet was discovered in April 2007, massing at least 2.5 times the mass of Jupiter (MJ). Despite its orbital distance more than that of Earth, the orbital period is less than a year, because the parent star is more massive than the Sun.
HD 154672 b is an extrasolar planet located approximately 210 light-years away in the constellation of Ara, orbiting the metal-rich and aged star HD 154672. This planet has a minimum mass five times that of Jupiter and orbits at about 60% the distance between the Earth to the Sun. Its orbit is very elliptical, which causes temperatures on the planet to vary significantly as it proceeds along its orbit. This planet was discovered in Las Campanas Observatory on September 5, 2008 using the radial velocity method. Along with HD 205739 b, the planets were the first to be discovered by the N2K Consortium using the Magellan Telescopes.
HD 153950 b is an extrasolar planet located approximately 162 light-years away. This planet was discovered on October 26, 2008 by Moutou et al. using the HARPS spectrograph on ESO's 3.6 meter telescope installed at La Silla Observatory in Atacama desert, Chile.
HD 215497 is a single star in the southern constellation of Tucana. It has an orange hue with an apparent visual magnitude of 8.96, which is too dim to be viewed with the naked eye. A 2015 survey ruled out the existence of any stellar companions at projected distances from 26 to 300 astronomical units. Based on parallax measurements, it is located at a distance of 132 light years from the Sun. The star is drifting further away with a radial velocity of +49 km/s, having come as close as 45 light-years some 774,000 years ago. The absolute magnitude of this star is 5.77.
An exoplanet is a planet located outside the Solar System. The first evidence of an exoplanet was noted as early as 1917, but was not recognized as such until 2016; no planet discovery has yet come from that evidence. What turned out to be the first detection of an exoplanet was published among a list of possible candidates in 1988, though not confirmed until 2003. The first confirmed detection came in 1992, with the discovery of terrestrial-mass planets orbiting the pulsar PSR B1257+12. The first confirmation of an exoplanet orbiting a main-sequence star was made in 1995, when a giant planet was found in a four-day orbit around the nearby star 51 Pegasi. Some exoplanets have been imaged directly by telescopes, but the vast majority have been detected through indirect methods, such as the transit method and the radial-velocity method. As of 1 May 2023, there are 5,366 confirmed exoplanets in 3,962 planetary systems, with 856 systems having more than one planet. This is a list of the most notable discoveries.
HIP 11915 b is an exoplanet orbiting the solar twin star HIP 11915 about 190 light-years (57 parsecs, or nearly 1.798×1015 km) from Earth in the constellation Cetus. It is notable as the first exoplanet to be discovered with an orbit and mass similar to that of Jupiter (essentially, a "Jupiter analog"), suggesting that its system may be similar to that of the Solar System. It orbits its star at a distance of approximately 4.8 AU. The exoplanet was found by using the radial velocity method, where periodic Doppler shifts of spectral lines of the host star suggest an orbiting object.
Kepler-419c is a super-Jupiter exoplanet orbiting within the habitable zone of the star Kepler-419, the outermost of two such planets discovered by NASA's Kepler spacecraft. It is located about 3,400 light-years from Earth in the constellation Cygnus. The exoplanet was found by using the transit timing variation method, in which the variations of transit data from an exoplanet are studied to reveal a more distant companion.
HIP 57274 d is an exoplanet orbiting the K-type main sequence star HIP 57274 about 84.5 light-years (26 parsecs, or nearly 8.022×1016 km) from Earth in the constellation Cetus. It orbits within the outer part of its star's habitable zone, at a distance of 1.01 AU. The exoplanet was found by using the radial velocity method, from radial-velocity measurements via observation of Doppler shifts in the spectrum of the planet's parent star.
HD 240237 b is a super-Jupiter exoplanet orbiting the K-type giant star HD 240237 about 4,900 light-years (1,500 parsecs, or nearly 4.6×1016 km) away from Earth in the constellation Cassiopeia. It orbits outside of the habitable zone of its star at a distance of 1.9 AU. The exoplanet was found by using the radial velocity method, from radial-velocity measurements via observation of Doppler shifts in the spectrum of the planet's parent star. The planet has a mildly eccentric orbit.
HD 3167 is a single, orange-hued star in the zodiac constellation of Pisces that hosts a system with three exoplanets. The star is too faint to be seen with the naked eye, having an apparent visual magnitude of 8.97. The distance to HD 3167 can be determined from its annual parallax shift of 21.1363 mas as measured by the Gaia space observatory, yielding a range of 154 light years. It has a relatively high proper motion, traversing the celestial sphere at the rate of 0.204″ per year. Since it was first photographed during the Palomar observatory sky survey in 1953, it had moved over 12.5″ by 2017. The star is moving away from the Earth with an average heliocentric radial velocity of +19.5 km/s.
