Community hub
Recent from talks
Contribute something to knowledge base
Content stats: 0 posts, 0 articles, 1 media, 0 notes
Members stats: 0 subscribers, 0 contributors, 0 moderators, 0 supporters
Subscribers
Supporters
Contributors
Moderators
Hub AI
HD 189733 b AI simulator
(@HD 189733 b_simulator)
Hub AI
HD 189733 b AI simulator
(@HD 189733 b_simulator)
HD 189733 b
HD 189733 b is an exoplanet in the constellation of Vulpecula approximately 64.5 light-years (19.8 parsecs) away from the Solar System. Astronomers in France discovered the planet orbiting the star HD 189733 on October 5, 2005, by observing its transit across the star's face. With a mass 11.2% higher than that of Jupiter and a radius 11.4% greater, HD 189733 b orbits its host star once every 2.2 days at an orbital speed of 152.0 kilometers per second (340,000 miles per hour), making it a hot Jupiter with poor prospects for extraterrestrial life.
The closest transiting hot Jupiter to Earth, HD 189733 b has been the subject of close atmospheric observation. Scientists have studied it with high- and low-resolution instruments, both from the ground and from space. Researchers have found that the planet's weather includes raining molten glass. HD 189733 b was also the first exoplanet to have its thermal map constructed, possibly to be detected through polarimetry, its overall color determined (deep blue), its transit viewed in the X-ray spectrum, and to have carbon dioxide confirmed as being present in its atmosphere.
In July 2014, NASA announced the discovery of very dry atmospheres on three exoplanets that orbited Sun-like stars: HD 189733 b, HD 209458 b, and WASP-12b.
On October 6, 2005, a team of astronomers announced the discovery of transiting planet HD 189733 b. The planet was then detected using Doppler spectroscopy. Real-time radial velocity measurements detected the Rossiter–McLaughlin effect caused by the planet passing in front of its star before photometric measurements confirmed that the planet was transiting. In 2006, a team led by Drake Deming announced detection of strong infrared thermal emission from the transiting exoplanet planet HD 189733 b, by measuring the flux decrement (decrease of total light) during its prominent secondary eclipse (when the planet passes behind the star).
The mass of the planet is estimated to be 16% larger than Jupiter's, with the planet completing an orbit around its host star every 2.2 days and an orbital speed of 152.5 kilometres per second (341,000 mph).
In 2024, high-resolution transmission spectroscopy using the ESPRESSO spectrograph provided refined measurements of HD 189733 b’s atmosphere. This study confirmed the presence of sodium (Na I) and reported the first detection of lithium (Li I) in the planet's atmosphere. The sodium absorption signal was found to be more blueshifted and shallower than previous estimates, indicating strong atmospheric winds. The analysis also revealed the challenges of separating planetary signals from stellar line distortions — known as Planet-Occulted Line Distortions (POLDs) — caused by the host star's rotation, limb darkening, and activity. These results highlight the need for more accurate stellar modeling in high-resolution studies of exoplanetary atmospheres.
On February 21, 2007, NASA released news that the Spitzer Space Telescope had measured detailed spectra from both HD 189733 b and HD 209458 b. The release came simultaneously with the public release of a new issue of Nature containing the first publication on the spectroscopic observation of the other exoplanet, HD 209458 b. A paper was submitted and published by the Astrophysical Journal Letters. The spectroscopic observations of HD 189733 b were led by Carl Grillmair of NASA's Spitzer Science Center.
In 2008, a team of astrophysicists appeared to have detected and monitored the planet's visible light using polarimetry, which would have been the first such success. This result seemed to be confirmed and refined by the same team in 2011. They found that the planet albedo is significantly larger in blue light than in the red, most probably due to Rayleigh scattering and molecular absorption in the red. The blue color of the planet was subsequently confirmed in 2013, which would have made HD 189733 the first planet to have its overall color determined by two different techniques. The measurements in polarized light have since been disputed by two separate teams using more sensitive polarimeters, with upper limits of the polarimetric signal provided therein.
HD 189733 b
HD 189733 b is an exoplanet in the constellation of Vulpecula approximately 64.5 light-years (19.8 parsecs) away from the Solar System. Astronomers in France discovered the planet orbiting the star HD 189733 on October 5, 2005, by observing its transit across the star's face. With a mass 11.2% higher than that of Jupiter and a radius 11.4% greater, HD 189733 b orbits its host star once every 2.2 days at an orbital speed of 152.0 kilometers per second (340,000 miles per hour), making it a hot Jupiter with poor prospects for extraterrestrial life.
The closest transiting hot Jupiter to Earth, HD 189733 b has been the subject of close atmospheric observation. Scientists have studied it with high- and low-resolution instruments, both from the ground and from space. Researchers have found that the planet's weather includes raining molten glass. HD 189733 b was also the first exoplanet to have its thermal map constructed, possibly to be detected through polarimetry, its overall color determined (deep blue), its transit viewed in the X-ray spectrum, and to have carbon dioxide confirmed as being present in its atmosphere.
In July 2014, NASA announced the discovery of very dry atmospheres on three exoplanets that orbited Sun-like stars: HD 189733 b, HD 209458 b, and WASP-12b.
On October 6, 2005, a team of astronomers announced the discovery of transiting planet HD 189733 b. The planet was then detected using Doppler spectroscopy. Real-time radial velocity measurements detected the Rossiter–McLaughlin effect caused by the planet passing in front of its star before photometric measurements confirmed that the planet was transiting. In 2006, a team led by Drake Deming announced detection of strong infrared thermal emission from the transiting exoplanet planet HD 189733 b, by measuring the flux decrement (decrease of total light) during its prominent secondary eclipse (when the planet passes behind the star).
The mass of the planet is estimated to be 16% larger than Jupiter's, with the planet completing an orbit around its host star every 2.2 days and an orbital speed of 152.5 kilometres per second (341,000 mph).
In 2024, high-resolution transmission spectroscopy using the ESPRESSO spectrograph provided refined measurements of HD 189733 b’s atmosphere. This study confirmed the presence of sodium (Na I) and reported the first detection of lithium (Li I) in the planet's atmosphere. The sodium absorption signal was found to be more blueshifted and shallower than previous estimates, indicating strong atmospheric winds. The analysis also revealed the challenges of separating planetary signals from stellar line distortions — known as Planet-Occulted Line Distortions (POLDs) — caused by the host star's rotation, limb darkening, and activity. These results highlight the need for more accurate stellar modeling in high-resolution studies of exoplanetary atmospheres.
On February 21, 2007, NASA released news that the Spitzer Space Telescope had measured detailed spectra from both HD 189733 b and HD 209458 b. The release came simultaneously with the public release of a new issue of Nature containing the first publication on the spectroscopic observation of the other exoplanet, HD 209458 b. A paper was submitted and published by the Astrophysical Journal Letters. The spectroscopic observations of HD 189733 b were led by Carl Grillmair of NASA's Spitzer Science Center.
In 2008, a team of astrophysicists appeared to have detected and monitored the planet's visible light using polarimetry, which would have been the first such success. This result seemed to be confirmed and refined by the same team in 2011. They found that the planet albedo is significantly larger in blue light than in the red, most probably due to Rayleigh scattering and molecular absorption in the red. The blue color of the planet was subsequently confirmed in 2013, which would have made HD 189733 the first planet to have its overall color determined by two different techniques. The measurements in polarized light have since been disputed by two separate teams using more sensitive polarimeters, with upper limits of the polarimetric signal provided therein.
Recent media
Recent media