HD 189733 b

HD 189733 b
Jupiter and HD 189733 b compared
Discovery[1]
Discovered byBouchy et al.
Discovery siteHaute-Provence Observatory
Discovery dateOctober 5, 2005
Doppler spectroscopy
Transit
Orbital characteristics[2]
0.03100 ± 0.0006 AU (4,638,000 ± 90,000 km)
Eccentricity<0.0039
2.218575200(77) d
53.2458048 h
152.0 km/s
Inclination85.580°±0.060°
Semi-amplitude201.3±1.6 m/s
StarHD 189733
Physical characteristics[2]
1.138±0.027 RJ
Mass1.123±0.045 MJ
Mean density
0.943+0.081
−0.072 g/cm3
21.5 m/s2 (2.2 g)
Albedo0.40±0.12 (290–450 nm)[3]
<0.12 (450–570 nm)[3]
0.076±0.016 (geometric)[4]
Temperature1,192±9 K (919 °C; 1,686 °F)[5]
1,490±68 K (1,220 °C; 2,220 °F)[6]

HD 189733 b is an exoplanet in the constellation of Vulpecula approximately 64.5 light-years (19.8 parsecs) away[7] 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.[1] 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 (152,000 meters per second; 340,000 miles per hour), making it a hot Jupiter with poor prospects for extraterrestrial life.[2]

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.[8] 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,[9][10] possibly to be detected through polarimetry,[11] its overall color determined (deep blue),[11][3] 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.[12]

  1. ^ a b Cite error: The named reference Bouchy2005 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference Bonomo2017 was invoked but never defined (see the help page).
  3. ^ a b c Cite error: The named reference Evans2013 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference Krenn2023 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Knutson2012 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Pass2019 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference GaiaDR3 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Khd was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Knutson2007 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Majeau2012 was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference Berdyugina2011 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference NASA-20140724 was invoked but never defined (see the help page).