spectorscopy Archives - Page 4 of 5 - Astrobiology

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 […]

Top panels: Results from the white light curve fit of the supreme-SPOON reduction for Visits 1 (left) and 2 (right), and fitted systematics models. The order 1 systematics-corrected light-curves are shown (teal points), binned for visual purposes, along with the best-fit transit model (black) and the systematics model including the GP component (red, with the GP scaled for visualization purposes). The vertical blue shaded regions indicate the three candidate flares with the highest signal-to-noise spectra and following typical flare evolution profiles (see Section C). Bottom panels: Spectroscopic light-curve fits to the two NIRISS/SOSS transits of GJ 9827 d from the supreme-SPOON reduction. The left panel corresponds to the first visit and the right panel to the second visit. We show the detrended broadband light-curve for order 2, and seven spectroscopic light-curves from order 1, from top to bottom. The best-fit astrophysical model is shown for each light-curve (black) and light-curves are offset relative to each other for clarity. -- astro-ph.EP

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

JWST/NIRISS Reveals The Water-rich Steam World Atmosphere of GJ 9827 d

by Keith CowingOctober 7, 2024October 7, 2024

With sizable volatile envelopes but smaller radii than the solar system ice giants, sub-Neptunes have been revealed as one of the most common types of planet in the galaxy.

This picture shows many tiny cells in which DNA is abundantly included inside the cells. First, the microbial cells were detected in fractures in the rock sample using an infrared imaging technique called O-PTIR spectroscopy. After that, they were stained with a green solution and analyzed using both a scanning electron microscope and then fluorescent microscopy. The combination of readings from these three imaging techniques enabled the researchers to confirm the indigenous and living microbial cells in the 2-billion-year-old rock fissure. -- University of Tokyo

Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Caves, Craters, Mountains, Subsurface, Lava Tubes, Fossils & Paleontology, Imaging & Spectroscopy, Microbiology & Virology, Press Release

A 2-billion-year-old Rock Is Home To Living Microbes

by Keith CowingOctober 4, 2024October 4, 2024

Pockets of microbes have been found living within a sealed fracture in 2-billion-year-old rock. The rock was excavated from the Bushveld Igneous Complex in South Africa, an area known for […]