Related topics: orbit · stars · planets · solar system

An ultra-short-period exoplanet discovered with TESS

Using NASA's Transiting Exoplanet Survey Satellite (TESS), an international team of astronomers has detected a new ultra-short-period exoplanet. The newfound alien world, designated HD 20329 b, orbits its host star in slightly ...

Astronomers detect new Jupiter-like exoplanet

Using radial velocity measurements, astronomers from Japan and China have detected a new exoplanet orbiting a G-type giant star. The newfound alien world is similar in mass to Jupiter but much hotter than the solar system's ...

Colliding magnetic fields reveal unknown planets

Ph.D. candidate astronomer Rob Kavanagh has developed mathematical models to better understand the interactions between exoplanets and stellar winds and to define features of exoplanets.

Observatory achieves 'first light' with new planet finder

A new planet-hunting instrument at W. M. Keck Observatory has achieved "first light," capturing its first data from the sky and marking an exciting chapter in the search for Earth-sized planets around other stars, which are ...

Searching for life on highly eccentric exoplanets

When we think about finding life beyond Earth, especially on exoplanets, we immediately want to search for the next Earth, or Earth 2.0. We want an exoplanet that orbits a star firmly in its habitable zone (HZ) with vast ...

Heaviest element yet detected in an exoplanet atmosphere

Using the European Southern Observatory's Very Large Telescope (ESO's VLT), astronomers have discovered the heaviest element ever found in an exoplanet atmosphere—barium. They were surprised to discover barium at high altitudes ...

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Extrasolar planet

An extrasolar planet, or exoplanet, is a planet beyond our Solar System, orbiting a star other than our Sun. As of June 2009[update], 353 exoplanets are listed in the Extrasolar Planets Encyclopaedia. The vast majority have been detected through radial velocity observations and other indirect methods rather than actual imaging. Most announced exoplanets are massive gas giant planets thought to resemble Jupiter, but this is a selection effect (bias) due to limitations in detection technology. Projections based on recent detections of much smaller worlds suggest that lightweight, rocky planets will eventually be found to outnumber extrasolar gas giants.

Extrasolar planets became a subject of scientific investigation in the mid-19th century. Many astronomers supposed that such planets existed, but they had no way of knowing how common they were or how similar they might be to the planets of our Solar System. The first confirmed radial velocity detection was made in 1995, revealing a gas giant planet in a four-day orbit around the nearby G-type star 51 Pegasi. The frequency of detections has tended to increase on an annual basis since then. It is estimated that at least 10% of sun-like stars have planets, and the true proportion may be much higher. The discovery of extrasolar planets sharpens the question of whether some might support extraterrestrial life.

Currently Gliese 581 d, the fourth planet of the red dwarf star Gliese 581 (approximately 20 light years from Earth), appears to be the best example yet discovered of a possible terrestrial exoplanet that orbits within the habitable zone surrounding its star. Although initial measurements suggested that Gliese 581 d resided outside the so-called "Goldilocks Zone", additional measurements place it firmly within.

This text uses material from Wikipedia, licensed under CC BY-SA