free-floating planet Archives - Astrobiology

ESO/L. Calçada/P. Delorme/Nick Risinger (skysurvey.org)/R. Saito/VVV Consortium via NASA Larger image

Exoplanets, -moons, -comets

Free Floating Exoplanets or Merely Detached?

by Keith CowingJuly 1, 2026July 1, 2026

[Astrophysical Journal] Microlensing surveys suggest the presence of a surprisingly large population of free-floating planets, with a rate of about two Neptunes per star.

Life-friendly moon -- A realistic depiction of a free-floating gas giant planet and its Earth-like moon © Dahlbüdding/DALL-E

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Habitable Zones, Imaging & Spectroscopy, Interstellar, Press Release

Conditions Suitable For Life On Distant Moons

by Keith CowingMarch 16, 2026March 16, 2026

Liquid water is considered essential for life. Surprisingly, however, stable conditions that are conducive to life could exist far from any sun. A research team from the Excellence Cluster ORIGINS […]

This illustration shows a rogue planet traveling through space. Credit: NASA/JPL-Caltech/R. Hurt (Caltech-IPAC)

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

A Free-floating-Planet Microlensing Event Caused By A Saturn-mass Object

by Keith CowingJanuary 6, 2026January 6, 2026

A population of free-floating planets is known from gravitational microlensing surveys. None have a directly measured mass, owing to a degeneracy with the distance, but the population statistics indicate that […]

The visual representation of the parameters used for modelling the SN II explosion. The progenitor system (top) can evolve into two distinct end states (bottom): the planet-moon system can stay bound to the neutron star or can leave the remnant and travel as a rogue system. The moons stay bound to the planet in both scenarios. -- astro-ph.EP

Astrogeology, Astronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Origin & Evolution of Life, Status Report

Life In The Dark: Potential Urability Of Moons Of Rogue Planets

by Keith CowingNovember 10, 2025November 10, 2025

Free-floating (rogue) planets are thought to be numerous in the Galaxy and may retain their moons after ejection from their natal systems. If those satellites acquire or preserve orbital eccentricity, […]

Maps of average lensing parameters of simulated microlensing events due to different BFFPs over the 2D space log10[s(AU)]−log10[Mtot(M⊕)]. Here, Fi and Fw are fractions of simulated microlensing events due to BFFPs with intermediate and wide caustic topologies, respectively. ρ? shows the source radius projected on the lens plane and normalized to the Einstein radius, Lc is a length scale for caustic curves, ∆c represents the caustic area, τ is a time scale for microlensing events due to BFFPs, and P is the orbital period of binary lenses. -- Monthly Notices of the Royal Astronomical Society

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

On the Detection of Binary Free-Floating Planets in the Roman Galactic Exoplanet Survey

by Keith CowingOctober 31, 2025October 31, 2025

The recent discovery of 40 binary Jupiter-mass free-floating planets in the Trapezium cluster by the James Webb Space Telescope (Pearson & McCaughrean 2023) has opened new windows and questions in […]

Velocity at infinity vs. parameter α for ejected test particles -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Interstellar, Status Report

Free-floating Planets Produced by Planet-Planet Scatterings: Ejection Velocity and Survival Rate of Their Moons

by Keith CowingAugust 27, 2025August 27, 2025

The discovery of numerous free-floating planets (FFPs) has intensified interest in their origins and dynamical histories.

Eccentricity of inner super-Earth vs. the semimajor axis ratio between the outer cold Jupiter and the inner super-Earth from observations, with the color of the symbol showing the semimajor axis of the inner super-Earth. The red boxes mark the systems with multiple inner super-Earths. -- astro-ph.EP

Exoplanets, -moons, -comets, Status Report

Dynamical Instability of Multi-planet Systems and Free-floating Planets

by Keith CowingJuly 31, 2025July 31, 2025

The ejection of planets by the instability of planetary systems is a potential source of free-floating planets.

Example evolution of an unstable system with 5 one-Neptune-mass planets. Top: the semi-major axes of individual planets are plotted as solid lines. Orbits' radial extents between pericenter and apocenter are indicated by the corresponding shaded regions. The black dashed line indicates the semi-major axis of an orbit with the same binding energy as the initial five-planet system. Bottom: planets' orbital inclinations, measured relative to the system's initial invariable plane, as functions of time. -- astro-ph.EP

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

Free Floating or Merely Detached?

by Keith CowingJuly 16, 2025July 16, 2025

Microlensing surveys suggest the presence of a surprisingly large population of free-floating planets, with a rate of about two Neptunes per star.

The color shows the product of the radiation flux at a wavelength of 3 µm and the square of the distance for the case of a prograde fall of the planet onto the disk. Model parameters: q = 5 AU, ω = 90◦ , i = 10◦ . The time moment t = 200 years from the beginning of the calculations is shown on the left, t = 290 years is shown in the center, and t = 500 years is shown on the right. The upper graphs correspond to the direction of the line of sight against the z axis, and the lower ones along the y axis. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Interstellar, Press Release, Stellar Cartography

Simulation of Images of Protoplanetary Disks After Collision with Free-floating Planets

by Keith CowingJuly 5, 2025July 5, 2025

Observational manifestations of disturbances in a protoplanetary disk caused by a collision with a massive planet are studied.

The magnification excess maps for planet-satellite configurations with log q = −1.5 and | log s| = 0.3. The color coding indicates fractional magnification differences between the 2L1S and 1L1S models. The maps with wide-separation (log s = 0.3) and close-separation (log s = −0.3) cases are displayed in the upper and lower panels, respectively. The left and right panels correspond to Earthmass and Neptune-class planets. The x-y coordinates denote the source positions in units of θE, with the positive x-axis aligned in the direction pointing from the planet (gold star) to the satellite (cyan star). Magenta circles indicate the source stars’ sizes (ρ = 0.33 for Earth-mass lenses and ρ = 0.08 for Neptune-class). Caustics are depicted in red, with the central caustic located near the planet and the satellite caustics positioned farther away. Each panel includes a lower-right inset offering a zoom-in view of the central caustics. -- astro-ph.EP

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

Detecting Exomoons In Free-Floating-Planet Events From Space-based Microlensing Surveys

by Keith CowingMay 30, 2025May 26, 2025

When a planet is ejected from its star-planet system due to dynamical interactions, its satellite may remain gravitationally bound to the planet.