TESS Archives

Mass-radius diagram for TOI-283 b (red star) and known transiting planets with mass determinations with a precision better than 30 % (parameters taken from the TEPCat database; Southworth 2011). Planets orbiting K-type stars (4000 ≤ Teff ≤ 5300 K) are marked with orange circles. The lines in the mass-radius diagram represent the composition models of Zeng et al. (2016, 2019) for planets with pure iron cores (100 % Fe, brown line), Earth-like rocky compositions (32.5 % Fe plus 67.5 % MgSiO3, dashed green line), Earth-like compositions with a 0.1% H2 envelope (dotted purple line), and a water world with a 0.1 % H2 gas envelope (dash-dotted blue line). We show some Solar System planets for reference (Venus, Earth, Uranus, and Neptune). -- astro-ph.EP

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

TOI-283 b: A Transiting Mini-Neptune In A 17.6-day Orbit Discovered With TESS And ESPRESSO

by Keith CowingOctober 23, 2025October 22, 2025

Super-Earths and mini-Neptunes are missing from our Solar System, yet they appear to be the most abundant planetary types in our Galaxy.

Top: Simulated EVE observation of an exocomet transit of a K7V at 100 pc expected during a 20 d stare at ∼20 Myr Theia 43 or 45 associations. We scale the optical light curve template used for the RZ Psc events into the NUV and NIR bands using a 50-50% weighted average of empirical extinction curves of ∼200 nm water ice (Kratschmer & Sorg 1985) and olivine dust (Huffman 1975). Bottom: Distribution of optical ADs versus SpT for 590 simulated detections. The SNR of the NUV detections (left) enable color differences due to composition (middle) and grain size (right) to be distinguished given the color predictions for the narrow-tail multiband comet models of K´alm´an et al. (2024). Each panel highlights the region in which EVE should detect exocomets given a 20% M-star disk fraction, but not for a 2.1% fraction. -- astro-ph.EP

Astronomy & Telescopes, Comets and Asteroids, Exoplanets, -moons, -comets, Icy Worlds, Imaging & Spectroscopy, Status Report

TESS Discovers a Second System of Transiting Exocomets in the Extreme Debris Disk of RZ Psc

by Keith CowingOctober 22, 2025October 22, 2025

We present the TESS discovery of only the second system of transiting exocomets with a sufficient number of events to measure the size distribution in the RZ Psc system, enabling […]

ONC-T images of (a) WASP-189 (image hyb2 onc 20240918 073620 tif l2b) and (b) MASCARA-1 (image hyb2 onc 20241130 093826 tif l2b) captured during transit events 10 and 12, respectively. The left panels show a single reduced ONC-T image (p t (x, y)) without hot pixel correction (i.e., data reduced assuming phot = 0 in Equation 1). The center panels show the same reduced images with hot pixel subtraction. The right panels show the reduced ONC-T image after applying a 3 × 3-pixel median filter and stacking all frames co-aligned on the target star, allowing the stellar positions to be clearly visualized. The host stars are marked with circles. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Missions & Hardware, Status Report

Demonstrating Exoplanet Transit Photometry From Space With A 15-mm Aperture Optical Navigation Camera On Hayabusa2

by Keith CowingOctober 20, 2025October 20, 2025

Observations of exoplanet transits by small satellites have gained increasing attention for reducing detection biases.

Phase folded transits of TOI-2345 b (purple) and TOI-2345 c (green) with the best-fit model from the joint fit in juliet in the top panel. The bottom panel shows the residuals. Left: TESS data. Right: CHEOPS data. -- astro-ph.EP

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

An Ultra-Short Period Super-Earth and Sub-Neptune Spanning the Radius Valley Orbiting the Kinematic Thick Disk Star TOI-2345

by Keith CowingOctober 16, 2025October 16, 2025

A crucial chemical link between stars and their orbiting exoplanets is thought to exist. If universal, this connection could affect the formation and evolution of all planets. Therefore, this potential […]

Orbital characterization of TOI-402 B around A using multiple datasets.

Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report, Stellar Cartography

Dynamical Architectures Of S-type Transiting Planets in Binaries II: A Dichotomy in Orbital Alignment of Small Planets in Close Binary Systems

by Keith CowingOctober 2, 2025October 2, 2025

Stellar multiplicity plays a crucial role in shaping planet formation and dynamical evolution. We present a survey of 54 TESS Objects of Interest (TOIs) within 300 pc that exhibit significant […]

The result of applying the trained Planet-FP SOMs on their respective training data. The plots showcase the position of each training event on the SOM pixel map with some added random scatter up to 0.5 from the position to enhance clarity. The synthetic planet events are plotted in green and each respectiveFPeventinorange.The plots highlight the clustering of the similarly shaped events and thus the effectiveness of each SOMind istinguishing between the Planetand FP candidates. As expected, the SOM is highly effective for EB based FP scenarios and increasingly less effective for diluted planet scenarios. -- astro-ph.EP

Exoplanets, -moons, -comets, Imaging & Spectroscopy, Press Release

RAVEN: RAnking And Validation Of ExoplaNets

by Keith CowingSeptember 24, 2025

We present RAVEN, a newly developed vetting and validation pipeline for TESS exoplanet candidates.

We present the discovery by the TESS mission of one transiting Neptune-sized planet, TOI-6223 b and two transiting super-Earths, TOI-1743 b and TOI-5799 b. We validate these planets using a statistical validation method, multi-color light curves and other ancillary observations. astro-ph.EP

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

TOI-1743 b, TOI-5799 b, TOI-5799 c and TOI-6223 b: TESS Discovery And Validation Of Four Super-Earth To Neptune-sized Planets Around M dwarfs

by Keith CowingSeptember 19, 2025September 19, 2025

We combined TESS and ground-based photometric data to constrain the physical properties of the planets. TOI-6223-b is slightly larger than Neptune (Rp=5.12+0.24−0.25 R⊕) orbiting an early M dwarf in 3.86 […]

Scientists have found thousands of exoplanets (planets outside our solar system) throughout the galaxy. Most can be studied only indirectly, but scientists know they vary widely, as depicted in this artist’s concept, from small, rocky worlds and gas giants to water-rich planets and those as hot as stars. Credit: NASA’s Goddard Space Flight Center Larger image

Astronomy & Telescopes, Exoplanets, -moons, -comets, Press Release

NASA’s Exoplanet Discovery Exceeds 6,000 Worlds

by Keith CowingSeptember 17, 2025September 17, 2025

The official number of exoplanets — planets outside our solar system — tracked by NASA has reached 6,000. Confirmed planets are added to the count on a rolling basis by […]

An example of difference image analysis of the known false positive TOI-164.01.

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

LEO-Vetter: Fully Automated Flux- and Pixel-Level Vetting of TESS Planet Candidates to Support Occurrence Rates

by Keith CowingSeptember 16, 2025September 16, 2025

The Transiting Exoplanet Survey Satellite (TESS) has identified several thousand planet candidates orbiting a wide variety of stars, and has provided an exciting opportunity for demographic studies.

Multi-night ZTF stacks centered at the nominal ephemeris position of 3I of periods from UT 2024 June 15 to UT 2025 May 9. Each stack is smoothed by a 2′′-wide Gaussian function for clarity. The 3σ uncertainty ellipses (appeared largely as a thin line due to very small semi-minor axis) are plotted in the upper-right corner of each panel. The images are color-inverted. -- astro-ph.EP

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Interstellar, Status Report

Prediscovery Activity of New Interstellar Object 3I/ATLAS: A Dynamically-Old Comet?

by Keith CowingSeptember 12, 2025September 12, 2025

We report on the prediscovery observations and constraints of the new interstellar comet 3I/2025 N1 (ATLAS), made by the Zwicky Transient Facility (ZTF), for the inbound leg of the comet […]

TESS

TOI-283 b: A Transiting Mini-Neptune In A 17.6-day Orbit Discovered With TESS And ESPRESSO

TESS Discovers a Second System of Transiting Exocomets in the Extreme Debris Disk of RZ Psc

Demonstrating Exoplanet Transit Photometry From Space With A 15-mm Aperture Optical Navigation Camera On Hayabusa2

An Ultra-Short Period Super-Earth and Sub-Neptune Spanning the Radius Valley Orbiting the Kinematic Thick Disk Star TOI-2345

Dynamical Architectures Of S-type Transiting Planets in Binaries II: A Dichotomy in Orbital Alignment of Small Planets in Close Binary Systems

RAVEN: RAnking And Validation Of ExoplaNets

TOI-1743 b, TOI-5799 b, TOI-5799 c and TOI-6223 b: TESS Discovery And Validation Of Four Super-Earth To Neptune-sized Planets Around M dwarfs

NASA’s Exoplanet Discovery Exceeds 6,000 Worlds

LEO-Vetter: Fully Automated Flux- and Pixel-Level Vetting of TESS Planet Candidates to Support Occurrence Rates

Prediscovery Activity of New Interstellar Object 3I/ATLAS: A Dynamically-Old Comet?

Relevance of the Avalon Assemblage as an Astrobiological Analog for Icy Ocean Worlds

The Climate and Potential Habitability of a Warm and Oxygenated Mars

Variable X-ray flux May Explain Variable Helium Escape From The Habitable-zone Exoplanet LHS 1140b

Spacetime Contactability in Galactic Civilization Networks: Contact Counts and Percolation

Surprisingly Enriched CO and CH4 in Halley-type Comet 13P/Olbers: Clues to Its Interstellar Heritage