HR 8799 d explained

HR 8799 d
Discoverer:Marois et al.
Discovery Site:Keck and Gemini
observatories in Hawaii
Discovered:November 13, 2008
Apsis:astron
Semimajor:~24 AU
Eccentricity:>0.04[1] [2]
Period:~100[3] y
Mean Radius:1.2
Mass:7[4]
Density:[5]
Rot Velocity:~
Single Temperature:1090[6]
Note:below

HR 8799 d is an extrasolar planet located approximately 129 light-years away in the constellation of Pegasus, orbiting the 6th magnitude Lambda Boötis star HR 8799. It has a mass between 5 and 10 Jupiter masses and a radius from 20 to 30% larger than Jupiter's. The planet orbits at 24 AU from HR 8799 with an eccentricity greater than 0.04 and a period of 100 years. Upon initial discovery, it was the innermost known planet in the HR 8799 system, but e, discovered later, is now known to be closer to their parent star. Along with two other planets orbiting HR 8799, this planet was discovered on November 13, 2008 by Marois et al., using the Keck and Gemini observatories in Hawaii. These planets were discovered using the direct imaging technique.[7] [8] [9]

Near infrared spectroscopy from 995 to 1769 nanometers made with the Palomar Observatory show evidence of acetylene, methane, and carbon dioxide, but ammonia is not definitively detected.[10] In 2021, the further detection of water and carbon monoxide in the planetary atmosphere was made with the Keck Planet Imager and Characterizer (KPIC).[11]

See also

Notes

  1. Stability of the directly imaged multiplanet system HR 8799: resonance and masses. 2010. 1408–1421 . 2 . 710 . Murray-Clay . 10.1088/0004-637X/710/2/1408 . Astrophys. J. . 0812.0011. 2010ApJ...710.1408F . Fabrycky . 11760422. 1 .
  2. The lower limit on the eccentricity is given for the case that the planet is in a 2:1 resonance with HR 8799 c, as suggested by stability constraints.
  3. Value given assuming the planet's orbit is circular and is being observed face-on.
  4. 1011.4918 . Marois . Zuckerman . Konopacky . Macintosh . Barman . Images of a fourth planet orbiting HR 8799 . Nature . 468 . 7327 . 1080–3 . 2010. 10.1038/nature09684 . 21150902. 2010Natur.468.1080M . 4425891 .
  5. Web site: Exoplanet HR 8799 d . 29 July 2024.
  6. Marois . Christian . November 2008 . Direct Imaging of Multiple Planets Orbiting the Star HR 8799 . . 322 . 5906 . 1348–1352 . 10.1126/science.1166585 . 0811.2606 . 19008415 . 2008Sci...322.1348M . Barman . Travis . Zuckerman . B. . Song . Inseok . Patience . Jennifer . Lafrenière . David . Doyon . René . 206516630 .
  7. Astronomers capture first images of newly-discovered solar system. W. M. Keck Observatory. 2008-11-13. 2008-12-02. dead. https://web.archive.org/web/20131126160805/http://www.keckobservatory.org/article.php?id=231. 2013-11-26.
  8. Gemini Releases Historic Discovery Image of Planetary First Family. Gemini Observatory. 2008-11-13. 2008-12-02.
  9. News: Scientists Publish First Direct Images of Extrasolar Planets. Joel. Achenbach. The Washington Post. 2008-11-13. 2008-12-02.
  10. B. R. Oppenheimer. Reconnaissance of the HR 8799 Exosolar System I: Near IR Spectroscopy. The Astrophysical Journal. 768. 24. 1303.2627. 2013ApJ...768...24O . 10.1088/0004-637X/768/1/24 . 2013. 1. 7173368.
  11. Wang . Jason J. . Ruffio . Jean-Baptiste . Morris . Evan . Delorme . Jacques-Robert . Jovanovic . Nemanja . Pezzato . Jacklyn . Echeverri . Daniel . Finnerty . Luke . Hood . Callie . Zanazzi . J. J. . Bryan . Marta L. . Bond . Charlotte Z. . Cetre . Sylvain . Martin . Emily C. . Mawet . Dimitri . Skemer . Andy . Baker . Ashley . Xuan . Jerry W. . Wallace . J. Kent . Wang . Ji . Bartos . Randall . Blake . Geoffrey A. . Boden . Andy . Buzard . Cam . Calvin . Benjamin . Chun . Mark . Doppmann . Greg . Dupuy . Trent J. . Duchêne . Gaspard . Feng . Y. Katherina . Fitzgerald . Michael P. . Fortney . Jonathan . Freedman . Richard S. . Knutson . Heather . Konopacky . Quinn . Lilley . Scott . Liu . Michael C. . Lopez . Ronald . Lupu . Roxana . Marley . Mark S. . Meshkat . Tiffany . Miles . Brittany . Millar-Blanchaer . Maxwell . Ragland . Sam . Roy . Arpita . Ruane . Garreth . Sappey . Ben . Schofield . Tobias . Weiss . Lauren . Wetherell . Edward . Wizinowich . Peter . Ygouf . Marie . 2 . 2107.06949 . Detection and Bulk Properties of the HR 8799 Planets with High-resolution Spectroscopy . The Astronomical Journal . 2021-07-14 . 162 . 4 . 148 . 10.3847/1538-3881/ac1349 . 2021AJ....162..148W . 235898867 . free .

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