An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of detection occurred in 1992. A different planet, initially detected in 1988, was confirmed in 2003. As of 1 August 2023, there are 5,484 confirmed exoplanets in 4,047 planetary systems, with 875 systems having more than one planet. The James Webb Space Telescope (JWST) is expected to discover more exoplanets, and also much more about exoplanets, including composition, environmental conditions and potential for life.
TrES-1b is an extrasolar planet approximately 523 light-years away in the constellation of Lyra. The planet's mass and radius indicate that it is a Jovian planet with a similar bulk composition to Jupiter. Unlike Jupiter, but similar to many other planets detected around other stars, TrES-1 is located very close to its star, and belongs to the class of planets known as hot Jupiters. The planet was discovered orbiting around GSC 02652-01324.
WASP or Wide Angle Search for Planets is an international consortium of several academic organisations performing an ultra-wide angle search for exoplanets using transit photometry. The array of robotic telescopes aims to survey the entire sky, simultaneously monitoring many thousands of stars at an apparent visual magnitude from about 7 to 13.
XO-1b is an extrasolar planet approximately 536 light-years away from Earth.
TrES-2b (Kepler-1b) is an extrasolar planet orbiting the star GSC 03549-02811 located 750 light years away from the Solar System. The planet was identified in 2011 as the darkest known exoplanet, reflecting less than 1% of any light that hits it. Reflecting less light than charcoal, on the surface the planet is said to be pitch black. The planet's mass and radius indicate that it is a gas giant with a bulk composition similar to that of Jupiter. Unlike Jupiter, but similar to many planets detected around other stars, TrES-2b is located very close to its star and belongs to the class of planets known as hot Jupiters. This system was within the field of view of the Kepler spacecraft.
Any planet is an extremely faint light source compared to its parent star. For example, a star like the Sun is about a billion times as bright as the reflected light from any of the planets orbiting it. In addition to the intrinsic difficulty of detecting such a faint light source, the light from the parent star causes a glare that washes it out. For those reasons, very few of the exoplanets reported as of April 2014 have been observed directly, with even fewer being resolved from their host star.
CoRoT-1b is a transiting extrasolar planet approximately 2,630 light-years away in the constellation of Monoceros. The planet was discovered orbiting the yellow dwarf star CoRoT-1 in May 2007. The planet was the first discovery by the French-led CoRoT Mission.
Epsilon Eridani b, also known as AEgir [sic], is an exoplanet approximately 10.5 light-years away orbiting the star Epsilon Eridani, in the constellation of Eridanus. The planet was discovered in 2000, and as of 2022 remains the only confirmed planet in its planetary system. It orbits at around 3.5 AU with a period of around 7.6 years, and has a mass around 0.6 times that of Jupiter. As of 2022, both the Extrasolar Planets Encyclopaedia and the NASA Exoplanet Archive list the planet as 'confirmed'.
TrES-4b is an extrasolar planet, and one of the largest exoplanets ever found, after WASP-12b, WASP-17b, CT Chamaeleontis b, GQ Lupi b and HD 100546 b. It was discovered in 2006, and announced in 2007, by the Trans-Atlantic Exoplanet Survey, using the transit method. It is approximately 1,400 light-years (430 pc) away orbiting the star GSC 02620-00648, in the constellation Hercules.
HAT-P-3b, also named Teberda, is an extrasolar planet that orbits the star HAT-P-3 approximately 450 light-years away in the constellation of Ursa Major. It was discovered by the HATNet Project via the transit method and confirmed with Doppler spectroscopy, so both its mass and radius are known quite precisely. Based on these figures it is predicted that the planet has about 75 Earth masses' worth of heavy elements in its core, making it similar to the planet HD 149026 b.
XO-5 is a yellow dwarf main sequence star located approximately 910 light-years away from Earth in the Lynx constellation. It has a magnitude of about 12 and cannot be seen with the naked eye but is visible through a small telescope.
XO-5b "Makropulos" is an extrasolar planet approximately 910 light years away in the constellation of Lynx. This planet was found by the transit method using the XO Telescope and announced in May 2008. It was also independently discovered by the HATNet Project. The planet has a mass and radius just slightly larger than that of Jupiter. This planet orbits very close to the G-type parent star, as it is typical for transiting planets, classing this as Hot Jupiter. It takes only 4.188 days to orbit at an orbital distance of 0.0488 AU).
GSC 03549-02811 is a yellow main-sequence star similar to the Sun. This star is located approximately 704 light-years away in the constellation of Draco. The apparent magnitude of this star is 11.41, which means it is not visible to the naked eye but can be seen with a medium-sized amateur telescope on a clear dark night. The age of this star is about 5 billion years.
GSC 03089-00929 is a magnitude 12 star located approximately 760 light-years away in the constellation of Hercules. This star is a G type main sequence star that is similar to but slightly cooler than the Sun. This star is identified in SIMBAD as a variable star per the 1SWASP survey.
GSC 02620-00648 is a double star in the constellation Hercules. The brighter of the pair is a magnitude 12 star located approximately 1,660 light-years away. This star is about 1.18 times as massive as the Sun.
WASP-17b is an exoplanet in the constellation Scorpius that is orbiting the star WASP-17. Its discovery was announced on 11 August 2009. It is the first planet discovered to have a retrograde orbit, meaning it orbits in a direction counter to the rotation of its host star. This discovery challenged traditional planetary formation theory. In terms of diameter, WASP-17b is one of the largest exoplanets discovered and at half Jupiter's mass, this made it the most puffy planet known in 2010. On 3 December 2013, scientists working with the Hubble Space Telescope reported detecting water in the exoplanet's atmosphere.
WASP-19, formally named Wattle, is a magnitude 12.3 star about 869 light-years away, located in the Vela constellation of the southern hemisphere. This star has been found to host a transiting hot Jupiter-type planet in tight orbit.
WASP-39b, officially named Bocaprins, is a "hot Jupiter" extrasolar planet discovered in February 2011 by the WASP project, notable for containing a substantial amount of water in its atmosphere. In addition WASP-39b was the first exoplanet found to contain carbon dioxide in its atmosphere, and likewise for sulfur dioxide.
GSC 03949-00967 is a G-type main-sequence star about 1190 light-years away. It is older than the Sun, yet is enriched by heavy elements compared to the Sun, having 160% of solar abundance.
