Fomalhaut is the brightest star in the southern constellation of Piscis Austrinus, the Southern Fish, and one of the brightest stars in the night sky. It has the Bayer designation Alpha Piscis Austrini, which is Latinized from α Piscis Austrini, and is abbreviated Alpha PsA or α PsA. This is a class A star on the main sequence approximately 25 light-years (7.7 pc) from the Sun as measured by the Hipparcos astrometry satellite. Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified.
Epsilon Indi, Latinized from ε Indi, is a star system located at a distance of approximately 12 light-years from Earth in the southern constellation of Indus. The star has an orange hue and is faintly visible to the naked eye with an apparent visual magnitude of 4.83. It consists of a K-type main-sequence star, ε Indi A, and two brown dwarfs, ε Indi Ba and ε Indi Bb, in a wide orbit around it. The brown dwarfs were discovered in 2003. ε Indi Ba is an early T dwarf (T1) and ε Indi Bb a late T dwarf (T6) separated by 0.6 arcseconds, with a projected distance of 1460 AU from their primary star.
A protoplanetary disk is a rotating circumstellar disc of dense gas and dust surrounding a young newly formed star, a T Tauri star, or Herbig Ae/Be star. The protoplanetary disk may also be considered an accretion disk for the star itself, because gases or other material may be falling from the inner edge of the disk onto the surface of the star. This process should not be confused with the accretion process thought to build up the planets themselves. Externally illuminated photo-evaporating protoplanetary disks are called proplyds.
Beta Pictoris is the second brightest star in the constellation Pictor. It is located 63.4 light-years (19.4 pc) from the Solar System, and is 1.75 times as massive and 8.7 times as luminous as the Sun. The Beta Pictoris system is very young, only 20 to 26 million years old, although it is already in the main sequence stage of its evolution. Beta Pictoris is the title member of the Beta Pictoris moving group, an association of young stars which share the same motion through space and have the same age.
2M1207, 2M1207A or 2MASS J12073346–3932539 is a brown dwarf located in the constellation Centaurus; a companion object, 2M1207b, may be the first extrasolar planetary-mass companion to be directly imaged, and is the first discovered orbiting a brown dwarf.
47 Ursae Majoris, formally named Chalawan, is a yellow dwarf star approximately 45.3 light-years from Earth in the constellation of Ursa Major. As of 2011, three extrasolar planets are believed to orbit the star.
2M1207b is a planetary-mass object orbiting the brown dwarf 2M1207, in the constellation Centaurus, approximately 170 light-years from Earth. It is one of the first candidate exoplanets to be directly observed. It was discovered in April 2004 by the Very Large Telescope (VLT) at the Paranal Observatory in Chile by a team from the European Southern Observatory led by Gaël Chauvin. It is believed to be from 5 to 6 times the mass of Jupiter and may orbit 2M1207 at a distance roughly as far from the brown dwarf as Pluto is from the Sun.
A debris disk, or debris disc, is a circumstellar disk of dust and debris in orbit around a star. Sometimes these disks contain prominent rings, as seen in the image of Fomalhaut on the right. Debris disks are found around stars with mature planetary systems, including at least one debris disk in orbit around an evolved neutron star. Debris disks can also be produced and maintained as the remnants of collisions between planetesimals, otherwise known as asteroids and comets.
The Beta Pictoris Moving Group is a young moving group of stars located relatively near Earth. A moving group, in astronomy, is a group of stars that share a common motion through space as well as a common origin. This moving group is named for Beta Pictoris.
HD 98800, also catalogued as TV Crateris, is a quadruple star system in the constellation of Crater. Parallax measurements made by the Hipparcos spacecraft put it at a distance of about 150 light-years away, but this value is in high error. The system is located within the TW Hydrae association (TWA), and has received the designation TWA 4.
TW Hydrae b is a likely extrasolar planet orbiting the young T Tauri star TW Hydrae approximately 176 light-years (54 parsecs, or nearly 1.665×1016 km) away in the constellation of Hydra. It is likely a Neptune-like planet orbiting at a distance of nearly 22 AU from its star.
HR 4796 is a binary star system in the southern constellation of Centaurus. Parallax measurements put it at a distance of 235 light-years from the Earth. The two components of this system have an angular separation of 7.7 arcseconds, which, at their estimated distance, is equivalent to a projected separation of about 560 Astronomical Units (AU), or 560 times the separation of the Earth from the Sun. The star and its ring resemble an eye, and it is sometimes known by the nickname "Sauron's Eye".
HD 141569 is an isolated Herbig Ae/Be star of spectral class A2Ve approximately 364 light-years away in the constellation of Libra. The primary star has two red dwarf companions at about nine arcseconds. In 1999, a protoplanetary disk was discovered around the star. A gap in the disk led to speculation about a possible extrasolar planet forming in the disk.
V429 Geminorum (BD+20°1790) is a young orange dwarf star in the constellation Gemini, located 90 light years away from the Sun. It is a BY Draconis variable, a cool dwarf which varies rapidly in brightness as it rotates.
AB Aurigae is a young Herbig Ae star in the Auriga constellation. It is located at a distance of approximately 531 light years from the Sun based on stellar parallax. This pre-main-sequence star has a stellar classification of A0Ve, matching an A-type main-sequence star with emission lines in the spectrum. It has 2.4 times the mass of the Sun and is radiating 38 times the Sun's luminosity from its photosphere at an effective temperature of 9,772 K. The radio emission from the system suggests the presence of a thermal jet originating from the star with a velocity of 300 km s−1. This is causing an estimated mass loss of 1.7×10−8 M☉ yr−1.
Strategic Explorations of Exoplanets and Disks with Subaru (SEEDS) is a multi-year survey that used the Subaru Telescope on Mauna Kea, Hawaii in an effort to directly image extrasolar planets and protoplanetary/debris disks around hundreds of nearby stars. SEEDS is a Japanese-led international project. It consists of some 120 researchers from a number of institutions in Japan, the U.S. and the EU. The survey's headquarters is at the National Astronomical Observatory of Japan (NAOJ) and led by Principal Investigator Motohide Tamura. The goals of the survey are to address the following key issues in the study of extrasolar planets and disks: the detection and census of exoplanets in the regions around solar-mass and massive stars; the evolution of protoplanetary disks and debris disks; and the link between exoplanets and circumstellar disks.
A circumstellar disc is a torus, pancake or ring-shaped accretion disk of matter composed of gas, dust, planetesimals, asteroids, or collision fragments in orbit around a star. Around the youngest stars, they are the reservoirs of material out of which planets may form. Around mature stars, they indicate that planetesimal formation has taken place, and around white dwarfs, they indicate that planetary material survived the whole of stellar evolution. Such a disc can manifest itself in various ways.
38 Virginis is an F-type main sequence star in the constellation of Virgo. It is around 108 light years distant from the Earth.
PDS 70 is a very young T Tauri star in the constellation Centaurus. Located 370 light-years from Earth, it has a mass of 0.76 M☉ and is approximately 5.4 million years old. The star has a protoplanetary disk containing two nascent exoplanets, named PDS 70b and PDS 70c, which have been directly imaged by the European Southern Observatory's Very Large Telescope. PDS 70b was the first confirmed protoplanet to be directly imaged.
A circumplanetary disk is a torus, pancake or ring-shaped accumulation of matter composed of gas, dust, planetesimals, asteroids or collision fragments in orbit around a planet. Around the planets, they are the reservoirs of material out of which moons may form. Such a disk can manifest itself in various ways.