Saved in:
Bibliographic Details
Main Authors: Venner, Alexander, Vanderburg, Andrew, Huang, Chelsea X., Dholakia, Shishir, Schwengeler, Hans Martin, Howell, Steve B., Wittenmyer, Robert A., Kristiansen, Martti H., Omohundro, Mark, Terentev, Ivan A.
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2601.19870
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912853554888704
author Venner, Alexander
Vanderburg, Andrew
Huang, Chelsea X.
Dholakia, Shishir
Schwengeler, Hans Martin
Howell, Steve B.
Wittenmyer, Robert A.
Kristiansen, Martti H.
Omohundro, Mark
Terentev, Ivan A.
author_facet Venner, Alexander
Vanderburg, Andrew
Huang, Chelsea X.
Dholakia, Shishir
Schwengeler, Hans Martin
Howell, Steve B.
Wittenmyer, Robert A.
Kristiansen, Martti H.
Omohundro, Mark
Terentev, Ivan A.
contents The transit method is currently one of our best means for the detection of potentially habitable "Earth-like" exoplanets. In principle, given sufficiently high photometric precision, cool Earth-sized exoplanets orbiting Sun-like stars could be discovered via single transit detections; however, this has not previously been achieved. In this work, we report a 10-hour long single transit event which occurred on the $V=10.1$ K-dwarf HD 137010 during K2 Campaign 15 in 2017. The transit is comparatively shallow ($225\pm10$ ppm), but is detected at high signal-to-noise thanks to the exceptionally high photometric precision achieved for the target. Our analysis of the K2 photometry, historical and new imaging observations, and archival radial velocities and astrometry strongly indicate that the event was astrophysical, occurred on-target, and can be best explained by a transiting planet candidate, which we designate HD 137010 b. The single observed transit implies a radius of $1.06^{+0.06}_{-0.05}$ $R_\oplus$, and assuming negligible orbital eccentricity we estimate an orbital period of $355^{+200}_{-59}$ days ($a=0.88^{+0.32}_{-0.10}$ AU), properties comparable to Earth. We project an incident flux of $0.29^{+0.11}_{-0.13}$ $I_\oplus$, which would place HD 137010 b near the outer edge of the habitable zone. This is the first planet candidate with Earth-like radius and orbital properties that transits a Sun-like star bright enough for substantial follow-up observations.
format Preprint
id arxiv_https___arxiv_org_abs_2601_19870
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle A Cool Earth-sized Planet Candidate Transiting a Tenth Magnitude K-dwarf From K2
Venner, Alexander
Vanderburg, Andrew
Huang, Chelsea X.
Dholakia, Shishir
Schwengeler, Hans Martin
Howell, Steve B.
Wittenmyer, Robert A.
Kristiansen, Martti H.
Omohundro, Mark
Terentev, Ivan A.
Earth and Planetary Astrophysics
The transit method is currently one of our best means for the detection of potentially habitable "Earth-like" exoplanets. In principle, given sufficiently high photometric precision, cool Earth-sized exoplanets orbiting Sun-like stars could be discovered via single transit detections; however, this has not previously been achieved. In this work, we report a 10-hour long single transit event which occurred on the $V=10.1$ K-dwarf HD 137010 during K2 Campaign 15 in 2017. The transit is comparatively shallow ($225\pm10$ ppm), but is detected at high signal-to-noise thanks to the exceptionally high photometric precision achieved for the target. Our analysis of the K2 photometry, historical and new imaging observations, and archival radial velocities and astrometry strongly indicate that the event was astrophysical, occurred on-target, and can be best explained by a transiting planet candidate, which we designate HD 137010 b. The single observed transit implies a radius of $1.06^{+0.06}_{-0.05}$ $R_\oplus$, and assuming negligible orbital eccentricity we estimate an orbital period of $355^{+200}_{-59}$ days ($a=0.88^{+0.32}_{-0.10}$ AU), properties comparable to Earth. We project an incident flux of $0.29^{+0.11}_{-0.13}$ $I_\oplus$, which would place HD 137010 b near the outer edge of the habitable zone. This is the first planet candidate with Earth-like radius and orbital properties that transits a Sun-like star bright enough for substantial follow-up observations.
title A Cool Earth-sized Planet Candidate Transiting a Tenth Magnitude K-dwarf From K2
topic Earth and Planetary Astrophysics
url https://arxiv.org/abs/2601.19870