TOI 700 Archives - Astrobiology

The left plots show the results of our injection and recovery test into our JWST observation of TOI 700 d, and the right for e.

Analog Studies, Astronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, Stellar Cartography

The JWST Search For Earth-Luna Analogs: Upper Limits On Exomoons And Refined Ephemerides For TOI 700 d And e

by Keith CowingApril 8, 2026April 8, 2026

While no conclusive detections of exomoons have been reported to date, planet formation theories predict that satellites should be a common outcome of the collisional dynamics in early extrasolar systems.

Upper panel: UV flux reaching the surface of the planet TOI-700 d for an Archean atmosphere, depicted in purple (fUV=1) and red (fUV=10), and a modern Earth-like atmosphere, in green (fUV=1) and blue (fUV=10). The different surface pressures, namely 4.0, 2.0, 1.0, and 0.5, are represented by tones gradually shifting towards lighter shades, indicating a transition from higher to lower pressure. The solar flux reaching both Earth’s exosphere and surface is depicted by solid black line and dashed black line, respectively, primarily for the purpose of comparison. Lower panel: a blowup of the flux scale depicted on the upper panel. -- astro-ph.EP

Analog Studies, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Status Report

Evaluating Habitability and Biosignature Detection on TOI-700 d: The Role of UV Environment and Atmospheric Pressure

by Keith CowingOctober 17, 2025October 17, 2025

M dwarfs have long been prime targets in the search for habitable exoplanets, owing to their abundance in the galaxy and the relative ease of detecting Earth-sized worlds within their […]

Family portrait of the five planets in the L 98-59 system showing their transit (or absence of transit) observed by TESS in the top panels and their Doppler signature from HARPS (red circles) and ESPRESSO (white/black circles for pre/post data) in the bottom panels. Only the error bars for ESPRESSO are shown to improve visibility. Black curves represent best-fit models from the transit analysis (top) and joint RV–TTV fit (bottom, using fixed orbital inclinations, see Sect. 4.5). For L 98- 59 e and f, 1000 predicted transit curves are shown in red using posterior samples from the RV–TTV fit and radii estimated from their minimum masses using spright (Parviainen et al. 2024). Planets e and f do not transit L 98-59. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report

Detailed Architecture Of The L 98-59 System And Confirmation Of A Fifth Planet In The Habitable Zone

by Keith CowingJuly 16, 2025July 16, 2025

The L 98-59 system, identified by TESS in 2019, features three transiting exoplanets in compact orbits of 2.253, 3.691, and 7.451 days around an M3V star, with an outer 12.83-day […]

TOI-700 e

Astronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report

A Second Earth-Sized Planet in the Habitable Zone of the M Dwarf, TOI-700

by Keith CowingJanuary 16, 2023January 16, 2023

We report the discovery of TOI-700 e, a 0.95 R⊕ planet residing in the Optimistic Habitable Zone (HZ) of its host star.

TOI 700 e

Astronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release

TESS Discovers TOI 700 Planetary System’s Second Earth-Sized World

by Keith CowingJanuary 10, 2023

Using data from NASA’s Transiting Exoplanet Survey Satellite, scientists have identified an Earth-size world, called TOI 700 e, orbiting within the habitable zone of its star – the range of […]