spectorscopy Archives - Page 4 of 5 - Astrobiology

Stellar flares observed in JWST/NIRISS time-series spectroscopy of TRAPPIST-1. Each column shows one flare event during transits of the TRAPPIST-1c or TRAPPIST-1f planets. Tow row: Light curves with the total flux (integrated over the full spectral range and normalized to the mean out-of-transit flux). Colored points indicate pre-flare (green), flare (orange), maximum flare light (red), and post-flare (blue) phases. Green and blue dashed lines mark the average pre- and post-flare flux levels. Middle row: Light curves of the normalized Hα flux. Bottom row: Time-resolved spectrograms (wavelength vs. time) normalized to the pre-flare spectrum. The shaded blue region shows the drop in flux caused by the planetary transit. For comparison, the time axis in all panels are aligned such that t = 0 corresponds to the beginning of the maximum flare light phase. In all four events, the total flux in the post-flare phase is systematically elevated relative to the pre-flare level. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Magnetic Fields, Electromagnetism, bioelectricity,, Press Release, Radiation, Space Weather & Heliophysics, TRAPPIST-1

Flares On TRAPPIST-1 Reveal The Spectrum Of Magnetic Features On Its Surface

by Keith CowingAugust 8, 2025August 8, 2025

TRAPPIST-1 is an M8 dwarf hosting seven known exoplanets and is currently one of the most frequently observed targets of the James Webb Space Telescope (JWST).

Visual extinction maps of the observed regions. Contours in the Barnard 1b map (left) correspond to [7, 14, 21, 28, 35, 42, 49, 56, 63, 70] mag levels. The contours in the IC 348 map (right) correspond to [6, 9, 12, 15, 18, 21, 24] mag levels. These maps were obtained from the τ850 optical depth maps in Zari et al. (2016) applying the K-band to V-band extinction ratio of ∼ 1/16 (Nishiyama et al. 2008). The crosses mark the pointings from where data was taken. Selected spectra of CH3OH lines at 90 GHz (Table 2) and H2S 11,0 → 10,1 line observed at different offsets are included in the maps. -- astro-ph.GA

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Interstellar, Status Report

Fine-tuning The Complex Organic Molecule Formation: Sulfur And CO Ice As Regulators Of Surface Chemistry

by Keith CowingJuly 24, 2025July 24, 2025

Grain-surface chemistry plays a crucial role in the formation of molecules of astrobiological interest, including H2S and complex organic molecules (COMs).

Planetary reflectivity (top; total flux) and polarization (bottom; polarized flux) as a function of scattering angle (or phase angle) and wavelength (colors). Glories, rainbows, Rayleigh scattering, and ocean glint generate strong polarization signatures and subtle reflectance signatures. (Figure from Vaughan et al. 2023). -- astro-ph.IM

Astronomy & Telescopes, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, Water/Hycean Worlds & Oceanography

Detecting Surface Liquid Water On Exoplanets

by Keith CowingJuly 8, 2025July 8, 2025

Planets with large bodies of water on their surface will have more temperate and stable climates, and such planets are the ideal places for life-as-we-know-it to arise and evolve.

(a): Total land fraction posteriors for the nominal Earth-like retrieval at different SNR with 50% cloud coverage. Given these conditions, an SNR of 20 is required for land detection. (b): Total land fraction posteriors for the nominal Earth-like retrieval at an SNR of 20 with varying cloud fractions from 30% to 100%. 100% results in a clear non-detection, and for an SNR of 20, cloud fractions of approximately 50-60% or less are necessary for a land detection. (c): Total land fraction posteriors for the nominal Earth-like retrieval at an SNR of 20 for more restrictive wavelength ranges. A wavelength coverage of at least 0.3 − 1.1 µm is required for detection (dark blue contour). Restricting to 0.4 − 1.1 µm (red contour) results in a non-detection. (d): Long wavelength cutoff tests for SNR of 20. We find the total land constraint to be relatively unaffected by the cutoff as long as it is beyond 1.1 µm (red contour). The pink contour, 0.2 − 0.7 µm does not permit land detection. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, Water/Hycean Worlds & Oceanography

Detecting Land With Reflected Light Spectroscopy To Rule Out Waterworld O2 Biosignature False Positives

by Keith CowingJuly 1, 2025July 1, 2025

The search for life outside our solar system is at the forefront of modern astronomy, and telescopes such as the Habitable Worlds Observatory (HWO) are being designed to identify biosignatures.

Properties of the atmosphere of WASP-121b. a, PT profiles inferred from the retrieval analysis for the dayside (red) and nightside (blue) atmospheres assuming thermochemical equilibrium. Condensation curves for refractory species are shown as labelled dash-dot lines. b, Normalized contribution functions for the dayside (red) and nightside (blue) atmospheres integrated across the G395H passband, illustrating the relative amount of radiation originating from each pressure level. c, Volume mixing ratios (VMRs) inferred for key molecules in the nightside atmosphere. d, The same as c for the dayside atmosphere. Solid lines in a, c, and d are the median values obtained at each pressure level and the shaded regions indicate the associated 1 sigma uncertainties defined by the 16th and 84th percentiles (68% credible interval) based on n = 1,000 posterior samples. -- astro-ph.EP

Astrochemistry, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Status Report

SiO and a Super-stellar C/O Ratio in the Atmosphere of the Giant Exoplanet WASP-121b

by Keith CowingJune 8, 2025June 8, 2025

Refractory elements such as iron, magnesium, and silicon can be detected in the atmospheres of ultrahot giant planets.

Typical abundances of 11 atom and ions in β Pic exocomets, relative to Fe ii and normalised by solar abundances. The numerical values used to build this figures are provided in Tab. 2. Grey crosses indicate the best-fit model with Saha’s equation -- astro-ph.EP

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

Abundances Of Refractory Ions In Beta Pictoris Exocomets

by Keith CowingMarch 25, 2025March 25, 2025

Beta Pic is a young, A5V star, known for harbouring a large number of exocomets, which frequently transit the star and produce absorption signatures.

From Lee et al. (2019b): the rotating disk around the FU Ori object V833 Ori. The imaged species is indicated in each panel. -- astro-ph.GA

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Imaging & Spectroscopy, Interstellar, Status Report

Observations Of Complex Organic Molecules In The Gas Phase Of The Interstellar Medium

by Keith CowingMarch 25, 2025March 25, 2025

Thanks to the advent of sensitive and broad bandwidth instrumentation, complex organic molecules (COMs) have been found in a wide variety of interstellar environments, not only in our Galaxy but […]

This image shows the precise location in the night sky of the galaxy JADES-GS-z14-0, an extremely tiny dot in the Fornax constellation. As of today, this is the most distant confirmed galaxy we know of. Its light took 13.4 billion years to reach us and shows the conditions of the Universe when it was only 300 million years old. The inset of the image shows a close-up of this primordial galaxy as seen with the Atacama Large Millimeter/submillimeter Array (ALMA). The inset is overlaid on an image taken with the NASA/ESA/CSA James Webb Space Telescope. Credit: ALMA (ESO/NAOJ/NRAO)/S. Carniani et al./S. Schouws et al/JWST: NASA, ESA, CSA, STScI, Brant Robertson (UC Santa Cruz), Ben Johnson (CfA), Sandro Tacchella (Cambridge), Phill Cargile (CfA) Larger image

Astrochemistry, Astronomy & Telescopes, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Imaging & Spectroscopy, Press Release

Oxygen Has Been Discovered In The Most Distant Known Galaxy JADES-GS-z14-0

by Keith CowingMarch 20, 2025March 20, 2025

Two different teams of astronomers have detected oxygen in the most distant known galaxy, JADES-GS-z14-0. The discovery, reported in two separate studies, was made possible thanks to the Atacama Large […]

Exoplanet GJ 9827d (artist’s concept) -- ESA

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Press Release, Water/Hycean Worlds & Oceanography

Hubble Finds Water Vapour In The Atmosphere Of Small Exoplanet GJ 9827d

by Keith CowingDecember 29, 2024December 28, 2024

Astronomers using the NASA/ESA Hubble Space Telescope observed the smallest exoplanet where water vapour has been detected in its atmosphere. At only approximately twice Earth’s diameter, the planet GJ 9827d […]

This image features NGC 346, one of the most dynamic star-forming regions in nearby galaxies, as seen by the NASA/ESA/CSA James Webb Space Telescope. NCG 346 is located in the Small Magellanic Cloud (SMC), a dwarf galaxy close to our Milky Way. Larger image

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

Planet-forming Discs Lived Longer In The Early Universe

by Keith CowingDecember 16, 2024December 16, 2024

In 2003, Hubble spotted a massive planet around a very old star, almost as old as the Universe. This implied that some planet formation happened when our Universe was very […]