The Kepler mission, conducted by NASA, concluded in 2018 after an impressive nine-year run dedicated to planetary exploration. During its operation, the space telescope made numerous discoveries, many of which were named after it. However, the wealth of data collected by Kepler is still being analyzed by exoplanet scientists.
Now, a group of researchers has brought new insights to a seven-planet system within Kepler’s vast database.
This planetary system revolves around a star known as Kepler 385, located approximately 4,670 light-years away. While some of its planets had been confirmed in 2014, others were still considered candidates. The updated catalogue compiled by exoplanet scientists now confirms the remaining planets in this system while providing new details about its unique characteristics.
The publication documenting this new catalogue is titled “Updated Catalog of Kepler Planet Candidates: Focus on Accuracy and Orbital Periods.” The primary author of this paper is Jack Lissauer, a research scientist at NASA’s Ames Research Center. The paper will be featured in the esteemed Journal of Planetary Science.
“We have compiled the most precise list of Kepler planet candidates along with their properties to date,” mentioned Lissauer. “NASA’s Kepler mission has played a crucial role in the discovery of a majority of known exoplanets, and this updated catalogue will allow astronomers to gain a deeper understanding of their characteristics.”
The Kepler 385 planetary system has been known to scientists for several years. Despite some of its planets being confirmed in 2014, ongoing advancements in analytical methods and refined data have led to new discoveries and a better understanding of this system.
The research team responsible for this catalogue claims that it encompasses all known Kepler planet candidates that orbit and transit only one star. One of the most intriguing features of this catalogue is the Kepler 385 system, which boasts seven planets situated incredibly close to their star, resulting in their continuous exposure to its intense heat. Although all seven are larger than Earth, they are still smaller than Neptune.
Kepler 385 is quite similar to our own Sun, albeit slightly larger and hotter. Specifically, it is 10% larger and approximately 5% hotter. It is one of only a few stars known to have more than six planets or planet candidates in its orbit.
The two innermost planets in the Kepler 385 system are both slightly larger than Earth. The updated catalogue suggests they are most likely composed of rock, potentially even possessing thin atmospheres. The remaining five planets are roughly twice the size of Earth and are expected to have substantial atmospheres.
“Our revised Kepler Exoplanet catalogue offers a comprehensive analysis of exoplanet properties,” commented co-author Jason Rowe, who holds the Canada Research Chair position in Exoplanet Astrophysics and is a Professor at Bishop’s University in Quebec, Canada.
“The improvements made to the analysis of planetary and stellar properties have allowed us to conduct an in-depth study of the fundamental properties of exoplanetary systems. This enables us to better comprehend these distant worlds by comparing them directly to our own Solar System and focusing on the intricate details of individual systems, such as Kepler-385.”
However, the significance of this new catalogue extends beyond the Kepler 385 system. The catalog includes nearly 4,400 planet candidates and 700 multi-planet systems deserving attention.
With improved measurements of the host stars, thanks in part to the data obtained from the European Space Agency’s Gaia spacecraft, the researchers were able to conduct a more precise analysis of the distribution of transit durations.
Transit durations play a vital role in the investigation of exoplanet distributions, particularly concerning orbital eccentricities. Eccentricities vary from zero, representing circular orbits, to highly elongated orbits.
Given that comprehensive eccentricity data is not available for most exoplanets, the researchers devised methodologies that can characterize the distribution of eccentricities for a population of transiting exoplanets. This is a crucial element of the new Kepler catalogue, leading to novel conclusions.
The primary conclusion relates to the nature of planetary orbits within multi-planet systems.
“Previous studies had suggested that systems with smaller planets and more transiting planets tend to exhibit smaller orbital eccentricities, but those results were reliant on complex models,” clarified co-author Eric Ford from Penn State University’s Department of Astronomy and Astrophysics.
“Our novel findings provide a more direct and model-independent demonstration that systems with more transiting planets tend to have more circular orbits.”
In terms of potential habitability, the Kepler 385 system falls short.
All seven planets within this system lie within the habitable zone, yet they are subjected to intense radiation. In fact, each planet receives more heat per area from its star than any planet in our Solar System. However, this research does not focus on habitability.
Instead, it centers around the creation of a detailed and accurate new catalogue for Kepler.
“More than a decade has passed since Kepler concluded its primary data collection,” the authors note. “Nevertheless, the list of Kepler planet candidates remains the largest and most consistent collection of exoplanets known to us.”
Now, with even more precise data at our disposal, who knows what other valuable insights can be garnered from studying these planets?
This article was originally published by Universe Today. Read the original article.
