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Updated: Jun 28, 2026
06:48
Surface Mapping of Earth-like Exoplanets using Single Point Light Curves
Published on: May 10, 2020
Direct imaging of multiple planets orbiting the star HR 8799
Christian Marois1, Bruce Macintosh, Travis Barman
1National Research Council Canada, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7, Canada. christian.marois@nrc-cnrc.gc.ca
Science (New York, N.Y.)
|November 15, 2008
Summary
Directly imaging exoplanets is challenging but reveals Jupiter-like planets. Observations of the HR 8799 system show three planets with masses 5-13 times Jupiter
Area of Science:
- Astronomy and astrophysics
- Exoplanetary science
- Direct imaging techniques
Background:
- Direct imaging of exoplanets is crucial for characterizing atmospheres and finding Earth-like planets.
- Challenges include small angular separation and high luminosity contrast between planets and stars.
Purpose of the Study:
- To demonstrate the capability of direct imaging for detecting and characterizing exoplanets.
- To analyze the HR 8799 system, a benchmark for high-contrast imaging.
Main Methods:
- Utilized high-contrast imaging observations from Keck and Gemini telescopes.
- Analyzed multi-epoch data to track orbital motion.
Main Results:
- Successfully imaged three planets orbiting the star HR 8799 at projected separations of 24, 38, and 68 astronomical units.
- Observed counter-clockwise orbital motion for all three planets.
- Estimated planetary masses between 5 and 13 Jupiter masses based on luminosity and system age.
Conclusions:
- The HR 8799 system serves as an excellent analogue for scaled-up outer solar system architectures.
- Direct imaging is a viable method for studying gas giants in wide orbits.
- Further characterization of exoplanetary atmospheres is enabled by this technique.
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