New Space and Tech

A 16 Hour Transit Observed By The Unistellar Network

By Keith Cowing
Press Release
November 10, 2022
Filed under , , , , , ,
A 16 Hour Transit Observed By The Unistellar Network
Transit light curve of Kepler-167 e (top) and residuals (middle) as observed by the Unistellar Network. Relative fluxes from individual data sets are plotted with different colors and symbols. The maximum likelihood model corresponding to the values in Table 1 is the red line and the time axis is defined as time since that model’s mid-transit time. The blue squares are weighted average fluxes of the combined data. The expected transit model and its transit start, middle, and end times are plotted as black broken lines. The bottom panel is the same as the top panel but zooms in on the times the transit occurred and only shows the weighted average fluxes. — astro-ph.EP

More than 5,000 exoplanets have been confirmed and among them almost 4,000 were discovered by the transit method.

However, few transiting exoplanets have an orbital period greater than 100 days. Here we report a transit detection of Kepler-167 e, a “Jupiter analog” exoplanet orbiting a K4 star with a period of 1,071 days, using the Unistellar ground-based telescope network. From 2021 November 18 to 20, citizen astronomers located in nine different countries gathered 43 observations, covering the 16 hour long transit.

Using a nested sampling approach to combine and fit the observations, we detected the mid-transit time to be UTC 2021 November 19 17:20:51 with a 1σ uncertainty of 9.8 minutes, making it the longest-period planet to ever have its transit detected from the ground. This is the fourth transit detection of Kepler-167 e, but the first made from the ground.

This timing measurement refines the orbit and keeps the ephemeris up to date without requiring space telescopes. Observations like this demonstrate the capabilities of coordinated networks of small telescopes to identify and characterize planets with long orbital periods.

Amaury Perrocheau, Thomas M. Esposito, Paul A. Dalba, Franck Marchis, Arin M. Avsar, Ero Carrera, Michel Douezy, Keiichi Fukui, Ryan Gamurot, Tateki Goto, Bruno Guillet, Petri Kuossari, Jean-Marie Laugier, Pablo Lewin, Margaret A. Loose, Laurent Manganese, Benjamin Mirwald, Hubert Mountz, Marti Mountz, Cory Ostrem, Bruce Parker, Patrick Picard, Michael Primm, Justus Randolph, Jay Runge, Robert Savonnet, Chelsea E. Sharon, Jenny Shih, Masao Shimizu, George Silvis, Georges Simard, Alan Simpson, Thusheeta Sivayogan, Meyer Stein, Denis Trudel, Hiroaki Tsuchiyama, Kevin Wagner, Stefan Will

Comments: 11 pages, 3 figures, 2 tables, accepted in ApJL
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Instrumentation and Methods for Astrophysics (astro-ph.IM)
Cite as: arXiv:2211.01532 [astro-ph.EP] (or arXiv:2211.01532v1 [astro-ph.EP] for this version)
Submission history
From: Thomas Esposito
[v1] Thu, 3 Nov 2022 00:26:48 UTC (2,417 KB)
Citizen Science

SpaceRef co-founder, Explorers Club Fellow, ex-NASA, Away Teams, Journalist, Space & Astrobiology, Lapsed climber.