[NASA] NASA’s SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer) space telescope is shedding light on brown dwarfs, celestial objects that blur the line […]
Exoplanets, -moons, -comets
![Stability map of the TOI-2211 system in the (Ωc , Ic) plane for the outer planet candidate TOI-2211.02. All other orbital parameters were fixed to the nominal solution from Table A.4. The colour scale shows the adopted stability indicator, with blue regions corresponding to stable configurations and red regions to unstable configurations. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/Searching-for.png?resize=1200%2C719&ssl=1)
Posted inWater/Hycean Worlds & Oceanography
Searching For Hot Water World Candidates With CHEOPS: II. A Low-density Super-Earth Orbiting The K Dwarf TOI-2211
[astro-ph.EP] Small exoplanets on close-in orbits are exposed to high levels of stellar irradiation, which can effectively remove low-mass primordial H/He envelopes through atmospheric escape.
![The Target Pixel File (TPF) of HS 0209+0832 from the TESS observations in Sector 71. The SPOC pipeline aperture is overplotted with shaded red squares. The position of HS 0209+0832 is demarcated by the number “1” and a white cross. All nearby sources within ∆m = 4 are displayed as red circles, with their size proportional to their brightness relative to HS 0209+0832. Each source is labelled by the rank of their projected distances from HS 0209+0832. The white arrows denote the orientation of the spacecraft during the observations. This figure was created with tpfplotter121 -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/Discovery-of-a.png?resize=1200%2C718&ssl=1)
Posted inExoplanets, -moons, -comets
Discovery Of A Second-generation Planet Candidate Accreting Onto A White Dwarf
[astro-ph.EP] Many white dwarfs accrete the debris of disrupted planetary bodies, detected in the form of metal-enrichment in their atmospheres, dusty or gaseous circumstellar discs, and photometric transits from debris.
![1 and 2-planet detectability thresholds for 4 specific configurations of planet mass and period ratios (close to and outside of resonance). The black grid points represent systems where only a single planet is detectable. Grey points show where both planets are detectable. The red line is a power law fit to the upper black contour, parametrising the 2-planet detection threshold. Similarly, the blue line is a power law fit to the lower contour and parametrises the 1-planet detection threshold. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/Detecting-multiple.png?resize=1200%2C716&ssl=1)
Posted inGaia Mission
Detecting Multiple Planets In Gaia Data Using Bayesian Model Selection
[astro-ph.EP] Gaia will soon provide a census of cold giant planets. However, an astrometric signal contains the superimposed reflex motion of all companions, so planetary signals cannot be treated individually.
![The fitted source and lens system positions as measured in the HST F606W (V −band; blue) and F814W (I−band; red) data. The contours show the 68%, 95%, and 99% confidence intervals for the V and I data, respectively. The measured V −band and I−band position of the (brighter) source star is nearly identical. We detect a weak (∼1.3σ) color-dependent centroid shift at the location of the lens system. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/First-Direct.png?resize=1200%2C720&ssl=1)
Posted inExoplanets, -moons, -comets
First Direct Identification Of A Multi-Star Microlens System Hosting A Planet
[astro-ph.EP] Nearly 25 years have passed since gravitational microlensing delivered its first exoplanet discoveries.
Posted inMars
Mars’ Oddest Cloud May Be Even Odder Than We Thought
[ESA]. Scientists using the European Space Agency’s Mars Express, in combination with a state-of-the-art meteorological model of the Red Planet, have found that there may be some very exotic physics […]
Posted inAstronomy & Telescopes
An Analytic Error-Budget Model for the Habitable Worlds Observatory Coronagraph: From Optical Disturbances to Flux-Ratio Noise
[astro-ph.IM] A coronagraph stability allocation must protect a planet measurement, not merely satisfy a contrast target. Residual starlight both generates photon noise and interferes with small field perturbations, coupling optical […]
![In top panels transits of TOI1408 b (left) and c (right) are shown along with their best fitting models (computed for one of likelihood maxima). In panels below the corresponding binned residuals and their uncertainties are plotted. Notice that there are a few occurrences when planets b and c transits partly overlapped with each other; in such a case all transit curves are plotted in the same graph. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/TOI-1408.png?resize=1200%2C720&ssl=1)
Posted inExoplanets, -moons, -comets
TOI-1408: The Limb Darkening Models, Photometric And Doppler Noises, And The Exoplanetary System
[astro-ph.EP] We perform a self-consistent analysis of Doppler and photometric TESS and ground-based transit observations available for TOI-1408, known to host a system with two planets orbiting near 2:1 mean-motion […]
Posted inExoplanets, -moons, -comets
Hybrid Worlds Are The Commonest Outcome Among The M-dwarf Sub-Neptunes Characterised With JWST
[astro-ph.EP] The sub-Neptunes orbiting M dwarfs are usually assigned to one of two classes: rocky cores beneath primordial hydrogen, or volatile-rich bodies formed beyond the water-ice line.
![Sky map of the Plato benchmark stars in Galactic coordinates. Different symbols indicate benchmark quality samples as defined in the text (Sect. 5.3). Symbol size increases with apparent brightness. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/Plato-benchmark.png?resize=1200%2C719&ssl=1)
Posted inPLATO
Plato Benchmark Stars I. The Initial Benchmark Sample I
[astro-ph.SR] The ESA PLATO mission aims to detect and characterise Earth-size exoplanets orbiting bright, late-type stars using high-precision photometry and asteroseismology.