A new analysis of data from NASA’s retired Kepler space telescope has revealed a system of seven giant planets around Kepler-385.
An artist’s concept of Kepler-385, the seven-planet system revealed in a new catalog of planet candidates discovered by NASA’s Kepler space telescope. Image credit: NASA / Daniel Rutter.
Kepler-385 is an F-type star located 4,944 light-years away in the constellation of Cygnus.
Also known as KIC 11968463, KOI-2433 or TIC 27082352, the star is about 10% larger and 5% hotter than the Sun.
The star hosts seven planets smaller than Neptune: Kepler-385b, c, d, e, f, g, and h.
The two inner planets, both slightly larger than Earth, are probably rocky and may have thin atmospheres.
The other five planets are larger — each with a radius about twice the size of Earth’s — and expected to be enshrouded in thick atmospheres.
This planetary system is among the highlights of a new Kepler catalog that contains almost 4,400 planet candidates, including more than 700 multi-planet systems.
It is one of only a few planetary systems known to contain more than six verified planets or planet candidates.
“We’ve assembled the most accurate list of Kepler planet candidates and their properties to date,” said Dr. Jack Lissauer, an astronomer at NASA’s Ames Research Center.
“NASA’s Kepler mission has discovered the majority of known exoplanets, and this new catalog will enable astronomers to learn more about their characteristics.”
While the Kepler mission’s final catalogs focused on producing lists optimized to measure how common planets are around other stars, Dr. Lissauer and colleagues were able to produce a comprehensive list of accurate information about each of the systems, making discoveries like Kepler-385 possible.
The new catalog uses improved measurements of stellar properties and calculates more accurately the path of each transiting planet across its host star.
This combination illustrates that when a star hosts several transiting planets, they typically have more circular orbits than when a star hosts only one or two.
After Kepler already showed us there are more planets than stars, the new study paints a more detailed picture of what each of those planets and their home systems look like, giving us a better view of the many worlds beyond our Solar System.
“Our primary catalog lists all known Kepler planet candidates that orbit and transit only one star,” the astronomers said.
“For completeness, we also provide an abbreviated listing of the properties of the two dozen non-transiting planets that have been identified around stars that host transiting planets discovered by Kepler.”
The team’s paper will be published in the Planetary Science Journal.
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Jack J. Lissauer et al. 2023. Updated Catalog of Kepler Planet Candidates: Focus on Accuracy and Orbital Periods. Planetary Science Journal, in press; arXiv: 2311.00238
