Astronomy & Telescopes Archives

Two new spaceborne Earth-observing instruments will help scientists better understand how global forests and ecosystems are affected by changes in climate and land use change. This image of the Amazon rainforest is from a 2010 global map of the height of the world’s forests based on multiple satellite datasets. Credits: NASA Earth Observatory

White Paper On Phototrophic Biosignatures: Research Priorities For The Search For Life On Other Worlds

by Keith CowingJuly 8, 2026July 8, 2026

[astro-ph.IM] Photosynthesis is of prime interest in the telescopic search for life beyond the Solar System, because, on Earth, oxygenic photosynthesis produces two strong “biosignatures,” global scale signs of life […]

Modes of interstellar expansion across two dimensions. The horizontal axis (expansion agent) runs from biological (crewed colonization, settlers, generation ships) to machine (autonomous probes, robotic seed systems). The vertical axis (visibility) runs from quiet (low-mass, low duty cycle, weak technosignatures) to loud (high-power, high waste heat, galaxy-scale signatures). The four quadrants summarize alternative expansion modes considered in the literature; the quiet expansion filter proposed in this paper occupies the lower-right quadrant (highlighted). -- [astro-ph.IM]

SETI & Technosignatures

Autonomous AI-Cosmoindustry and the Quiet Expansion Filter: A Threshold-Based Resolution of the Fermi Paradox

by Keith CowingJuly 8, 2026July 8, 2026

[astro-ph.IM] The Fermi paradox is sharpened, not weakened, by plausible extrapolations of artificial intelligence, autonomous robotics, in-situ resource utilization, orbital manufacturing, space-based computing, and uncrewed interstellar probes.

Astrometric reflex signal (color scale, µas) induced by an exomoon as a function of moon mass and system distance

Astronomy & Telescopes

A Scalable Path to Astrometric Exomoon Discoveries with the Nautilus Space Observatory

by Keith CowingJuly 8, 2026July 8, 2026

[astro-ph.IM] Moons orbiting exoplanets (exomoons) can be detected through the reflex motion they impart to their host planet, which is recoverable in relative star-planet astrometric time series.

The mid-infrared transmission spectrum of TOI-270 d obtained with the JWST MIRI LRS instrument and the JExoRES pipeline. The data points with error bars (in dark red) show the observed spectrum. The horizontal error bars correspond to the spectral bin width. The dark blue curve denotes the median retrieved spectral fit to this MIRI dataset using the canonical retrieval discussed in Section 3.2, while the two lighter shaded regions denote the 1σ and 2σ intervals. The yellow points denote the binned median model. -- astro-ph.EP

Exoplanets, -moons, -comets

The Mid-Infrared Transmission Spectrum of the Temperate Sub-Neptune TOI-270 d

by Keith CowingJuly 8, 2026July 7, 2026

[astro-ph.EP] Observations of temperate sub-Neptunes with JWST have ushered in a new era for atmospheric characterization of small exoplanets.

A selection of the data products that can be generated using 2D-CARMApy.

Exoplanets, -moons, -comets

CARMApy: An Open-Source Python Framework for Simulating Microphysical Clouds in Planetary Atmospheres

by Keith CowingJuly 8, 2026July 7, 2026

[astro-ph.EP] CARMApy is a new open-source python code that performs bin-scheme microphysical modeling of clouds in exoplanet atmospheres.

This image of interstellar comet 3I/ATLAS was taken on 18 January 2026 with the FORS2 instrument on ESO’s Very Large Telescope (VLT). It is a stack of several images spanning 14 minutes. As the comet moves on the sky, the stars appear as trails in the background. Credit: ESO/O. Hainaut

Comets and Asteroids

Older Than The Sun: Astronomers Find New Clues To The Origin Of Interstellar Comet 3I/ATLAS

by Keith CowingJuly 7, 2026July 7, 2026

[ESO] Astronomers have used the European Southern Observatory’s Very Large Telescope (ESO’s VLT) to study the composition of 3I/ATLAS, the brightest interstellar object ever seen, in detail.

Surveying the Trade Space with Engineering Architecture Concepts (EACs) From right to left, these are EACs 1, 2, and 3. EAC-1 is a 6m, segmented, off-axis telescope. EAC-2 is the same but uses a round keystone mirror and surrounding segments. EAC-3 is an 8m on-axis telescope with round segments. Each model has an extendable barrel, not pictured here, to protect its primary mirrors from impact damage with micrometeorites. NASA Goddard/Conceptual Image Labs -- astro-ph.IM

Astronomy & Telescopes

The Habitable Worlds Observatory Technology Development Plan

by Keith CowingJuly 7, 2026July 7, 2026

[astro-ph.IM] The Habitable Worlds Observatory (HWO) is NASA’s next large space telescope, selected by the 2020 Decadal Survey in Astronomy and Astrophysics to search for and characterize habitable exoplanets while […]

Carbon ion chemistry network. The red arrows indicate endoergic reactions, which proceed rapidly at high T or in regions with significant FUV-pumped H∗ 2 . We also show possible reactions (dashed) involving Polyaromatic Hydrocarbon (PAH) and Hydrogenated Amorphous Carbon (HAC) grains, which may be relevant in certain conditions. The figure is adapted from Goicoechea et al. (2025a). -- astro-ph.GA

Astrochemistry

Searching For The Elusive CH2+ With The James Webb Space Telescope. Another Carbocation To Constrain Astrochemical Networks

by Keith CowingJuly 7, 2026July 7, 2026

[astro-ph.GA] Carbocations are key species in interstellar chemistry, providing entry points for building larger hydrocarbons. CH+, and more recently, CH3+, have been detected. Other carbocations await detection to provide a […]

Integrated MIRI-MRS spectrum of HK Tau A (top) and B (bottom) in grey, with the black line representing the continuum baseline. In the top panel, the insets zoom into wavelength regions where molecular emission from 12CO, H2O, 12CO2 , and H2 is visible. In the bottom panel, the shaded bands in the indicate the main ices absorption regions. H2 rotational lines are marked with blue ticks, and gas emission features are labelled where present. -- astro-ph.EP

Astrochemistry

MINDS: Complementary Inclinations In The Binary Ssystem HK Tau Reveal Gas- And Ice-phase Chemistry

by Keith CowingJuly 7, 2026July 7, 2026

[astro-ph.EP] HK Tau is a roughly equal mass pre-main sequence binary system consisting of a low-inclination primary (57 deg) and an edge-on (83 deg) secondary. We present JWST/MIRI observations targeting […]

The transmission spectrum of TOI-1231 b. The observed JWST spectrum and retrieved model fits are shown for the fiducial retrieval using the JexoPipe data, considering the six prominent CNO molecules, with a single offset and no stellar heterogeneity, as discussed in Section 3. For visual clarity, the data shown here have been binned to R∼50. A retrieved offset of 79.38 ppm has been added to the NIRSpec data. The dark blue line indicates the median retrieved spectrum, with the shaded regions indicating the 1σ and 2σ uncertainties. The yellow points show the median retrieved spectrum binned at the same resolution as the plotted data. -- astro-ph.EP

Exoplanets, -moons, -comets

Transmission Spectrum of the Benchmark Temperate Exo-Neptune TOI-1231 b

by Keith CowingJuly 7, 2026July 7, 2026

[astro-ph.EP] The JWST is revolutionizing our understanding of the temperate sub-Neptune population through atmospheric spectroscopy.

Astronomy & Telescopes

White Paper On Phototrophic Biosignatures: Research Priorities For The Search For Life On Other Worlds

Autonomous AI-Cosmoindustry and the Quiet Expansion Filter: A Threshold-Based Resolution of the Fermi Paradox

A Scalable Path to Astrometric Exomoon Discoveries with the Nautilus Space Observatory

The Mid-Infrared Transmission Spectrum of the Temperate Sub-Neptune TOI-270 d

CARMApy: An Open-Source Python Framework for Simulating Microphysical Clouds in Planetary Atmospheres

Older Than The Sun: Astronomers Find New Clues To The Origin Of Interstellar Comet 3I/ATLAS

The Habitable Worlds Observatory Technology Development Plan

Searching For The Elusive CH2+ With The James Webb Space Telescope. Another Carbocation To Constrain Astrochemical Networks

MINDS: Complementary Inclinations In The Binary Ssystem HK Tau Reveal Gas- And Ice-phase Chemistry

Transmission Spectrum of the Benchmark Temperate Exo-Neptune TOI-1231 b

Determining The “Biosignature Threshold” For Life Detection On Biotic, Abiotic, or Prebiotic Worlds.

Icy Ocean Planet Research: NASA ROSES-25 Amendment 71: New Opportunity A.16 Cryosphere

Global Carbon Fixation In Earth’s Subsurface Biosphere

tinyRNA-seq: An Optimized Approach To Sequencing Tiny RNAs And Primitive RNA Genomes

Stellar Flares Rather Than High Tint As Possible Cause For the Missing Methane In Young Exoplanets: The Case Study of V1298-Tau b