Stellar Cartography Archives

Normalised observed spectrum of the star GJ 880 as black dashed line, and best-fit model (synthetic spectrum predicted by the Payne’s ANN for the parameters given in Table 2) as orange solid line. Grey shaded areas indicate the location of the line mask we used. Derived parameters for this star are Teff: 3649 K, log g: 4.8 dex, and [Fe/H]: 0.25 dex -- astro-ph.SR

Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, Stellar Cartography

Performance of the Stellar Abundances and Atmospheric Parameters Pipeline Adapted for M Dwarfs I. Atmospheric Parameters from the Spectroscopic Module

by Keith CowingFebruary 14, 2025February 14, 2025

M dwarfs are important targets in the search for Earth-like exoplanets due to their small masses and low luminosities. Several ongoing and upcoming space missions are targeting M dwarfs for […]

Astronomy & Telescopes, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Missions & Hardware, PLATO, Status Report, Stellar Cartography

The PLATO Multiple Star Working Group (MSWG)

by Keith CowingFebruary 13, 2025April 27, 2026

The PLATO mission is scheduled for launch in December 2026. It is an ESA M-class mission designed to find small planets around bright stars via the transit technique.

GP model fit to the RV data. Left panel shows the entire RV time series in black and the GP model in blue, with residuals plotted in the lower panel, to demonstrate that a quasiperiodic GP model was able to capture the long-period variation caused by the stellar magnetic cycle. The gray shaded region is shown in the right panel. The right panel shows the same model and data over a centrally located 60 day baseline, to highlight the effects of the 9.42 day stellar rotation period. -- astro-ph.EP

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

The Magnetically Induced Radial Velocity Variation of Gliese 341 and an Upper Limit to the Mass of Its Transiting Earth-sized Planet

by Keith CowingFebruary 13, 2025February 13, 2025

The Transiting Exoplanet Survey Satellite (TESS) mission identified a potential 0.88 REarth planet with a period of 7.577 days, orbiting the nearby M1V star GJ 341 (TOI 741.01).

This artist’s concept visualizes a super-Neptune world orbiting a low-mass star near the center of our Milky Way galaxy. Scientists recently discovered such a system that may break the current record for fastest exoplanet system, traveling at least 1.2 million miles per hour, or 540 kilometers per second. NASA/JPL-Caltech/R. Hurt (Caltech-IPAC)

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

The Fastest Exoplanet System Yet Discovered

by Keith CowingFebruary 11, 2025February 11, 2025

Astronomers may have discovered a scrawny star bolting through the middle of our galaxy with a planet in tow. If confirmed, the pair sets a new record for the fastest-moving […]

Relations between mutual inclination and stellar metallicity and stellar mass after sample control. Left: stellar metallicity vs. mutual inclination plot for a subsample of 78 systems selected to minimize the influence of stellar mass. Right: stellar mass vs. mutual inclination plot for a subsample of 81 systems selected to minimize the influence of stellar metallicity. Unlike [Fe/H] vs. ∆i, the correlation between stellar mass and ∆i is not statistically significant in our sample, although we cannot completely rule out such a correlation. See Section 5 for more details. -- astro-ph.EP

Astrogeology, Exoplanets, -moons, -comets, Status Report, Stellar Cartography

Short-Period Small Planets with High Mutual Inclinations are more Common around Metal-Rich Stars

by Keith CowingFebruary 10, 2025

We present a correlation between the stellar metallicities and the mutual inclinations of multi-planet systems hosting short-period small planets (a/Rs<12, Rp<4Re). We analyzed 89 multi-planet systems discovered by Kepler, K2, […]

Artist impression of exoplanet Gaia-4b -- ESA

Astronomy & Telescopes, Brown Dwarfs, Exoplanets, -moons, -comets, Gaia Mission, Imaging & Spectroscopy, Press Release, Stellar Cartography

Wobbling Stars Reveal Hidden Companions In Gaia Data

by Keith CowingFebruary 4, 2025

New research, published today, uses data collected by ESA’s Gaia spacecraft to confirm the existence of two mysterious celestial objects. Gaia-4b is a ‘Super-Jupiter’ exoplanet, and Gaia-5b a brown dwarf. […]

Regions surveyed to identify sources likely to present spectra with detectable ice features of H2O, CO, CO2, 13CO2, and other species in the 3 − 5 µm wavelength range where SPHEREx is sensitive. Upper panel: The regions are projected onto a background greyscale image representing the Rowles & Froebrich (2009) extinction map stretched from AV = 0 (white) to 2 mag (black). Solid red lines enclose the fields from which candidate SPHEREx targets have been drawn. Dotted blue lines indicate the boundaries of nearby molecular clouds as defined by Zucker et al. (2019). Red circles indicate the locations and sizes of ‘dark nebulae’ identified on the Palomar plates by Lynds (1962). Lower panel: same symbols as the upper panel, but the background greyscale image is the integrated 12CO(1-0) line intensity survey executed with the CfA 1.2 m telescope and its southern hemisphere counterpart (e.g., Dame et al. 2001; Heyer & Dame 2015). The inverted greyscale stretch ranges from −1 to 25 K km s−1, to indicate the extensive CO survey footprint. The white background indicates regions unobserved by the CfA CO survey except for the Magellanic Clouds (the SMC and LMC maps are described respectively in Rubio et al. (1991) and Cohen et al. (1988)). -- astro-ph.GA

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Imaging & Spectroscopy, Missions & Hardware, Status Report, Stellar Cartography

The SPHEREx Target List of Ice Sources (SPLICES)

by Keith CowingJanuary 31, 2025January 31, 2025

One of the primary objectives of the SPHEREx mission is to understand the origin of molecules such as H2O, CO2, and other volatile compounds at the early stages of planetary […]

A grand summary highlighting all the physical processes that sculpt the small planet population in the radius-period space. Plotted in contour is the Gaussian Kernel density estimation of Kepler candidates from Data Release 25 (Thompson et al. 2018). We do not correct for detection biases as these contours are for illustration purpose. Rocky planets are expected to be found in a region bounded by the evaporation/primordial gap (orange dashed line / light grey region), tides (red dashed line), and magnetic drag (blue dashed line). All the boundaries drawn in this figure assume system age of 5 Gyr, M⋆ = M⊙, and B⋆,i =100 G. Varying these stellar parameters can widen or shrink the allowable region of surviving rocky planets. -- astro-ph.EP

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

Carving the Edges of the Rocky Planet Population

by Keith CowingJanuary 31, 2025

Short-period planets provide ideal laboratories for testing star-planet interaction. Planets that are smaller than ∼2R⊕ are considered to be largely rocky either having been stripped of or never having acquired […]

Cartoon depiction of the sulfur-cycle in different planetary regimes. In the Earthlike case (A), atmospheric SO2 is scrubbed from the atmosphere by wet deposition (19). In the Venus-like case with high-UV irradiation (B), for example irradiation by the Sun, SO2 can be abundant in the deep atmosphere, however in the upper atmosphere SO2 is efficiently catalysed into H2SO4 by UV photons and subsequent reaction with H2O (80). In the Venus-like case with low-UV irradiation (C), such as irradiation by a low-UV M-dwarf, SO2 can survive in the upper atmosphere (20), potentially enabling SO2 to be identified in spectroscopic observation and thereby revealing the lack of a surface water ocean. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Habitable Zones, Status Report, Stellar Cartography

Tracing the Inner Edge of the Habitable Zone with Sulfur Chemistry

by Keith CowingJanuary 31, 2025January 31, 2025

The circumstellar liquid-water habitable zone guides our search for potentially inhabited exoplanets, but remains observationally untested. We show that the inner edge of the habitable zone can now be mapped […]

1-to-1 plots of our inferred abundances vs. the reported abundances of M dwarfs from the Hyades cluster using either our FGK-M sample (top row) or the Souto et al. (2022) sample (bottom row) as the training set. The points are colored by the χ2 of the flux model spectral fit. We report the rms scatter between the inferred and reported abundance values from Wanderley et al. (2023) in the top left of each plot, and the scatter of the reported values for that label below. The rms scatter from training on our FGK-M sample (∼0.05 dex) are lower than those from training on the Souto et al. (2022) sample (∼0.07−0.08 dex). -- astro-ph.SR

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

A Data-Driven M Dwarf Model and Detailed Abundances for ∼17,000 M Dwarfs in SDSS-V

by Keith CowingJanuary 29, 2025September 18, 2025

The cool temperatures of M dwarf atmospheres enable complex molecular chemistry, making robust characterization of M dwarf compositions a long-standing challenge.

Stellar Cartography

Performance of the Stellar Abundances and Atmospheric Parameters Pipeline Adapted for M Dwarfs I. Atmospheric Parameters from the Spectroscopic Module

The PLATO Multiple Star Working Group (MSWG)

The Magnetically Induced Radial Velocity Variation of Gliese 341 and an Upper Limit to the Mass of Its Transiting Earth-sized Planet

The Fastest Exoplanet System Yet Discovered

Short-Period Small Planets with High Mutual Inclinations are more Common around Metal-Rich Stars

Wobbling Stars Reveal Hidden Companions In Gaia Data

The SPHEREx Target List of Ice Sources (SPLICES)

Carving the Edges of the Rocky Planet Population

Tracing the Inner Edge of the Habitable Zone with Sulfur Chemistry

A Data-Driven M Dwarf Model and Detailed Abundances for ∼17,000 M Dwarfs in SDSS-V

Astrobiologist Dale Andersen’s Antarctic Field Report: Preview: Fall 2026 Lake Untersee Field Season

ALMA Reveals Planetary Formation Structures In Small Disks

Compatible Comma-Free Codes and the Origin of the Genetic Code

Simulations Of The Evolving Ozone Layer: Implications For The Early Earth, Exoplanets, And The Search For Life

VUV And mid-UV Photoabsorption Cross Sections Of Thin Films Of Glycine And Alanine: Application To Their Photochemistry In The Solar System