Habitable Worlds Observatory Archives

An example of a three-dimensional cube depicting the spatial dimensions and a visible spectral dimension. A 3D cube is one of the main data products from an Integral Field Spectrograph. -- astro-ph.IM

Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Missions & Hardware, Status Report

PyISH: Python Integral Field Spectroscopy Simulation for Habitable Worlds Observatory (HWO)

by Keith CowingJanuary 23, 2026January 23, 2026

The Habitable Worlds Observatory (HWO) will be a large ultraviolet/optical/near-infrared space telescope operating at the Sun-Earth Lagrange point L2.

A decision tree strategy for characterizing Earth-like exoplanets (Young et al. 2024). This tree indicates which gasses to observe, and in which order, to detect the biosignatures of Earth through time and rule out relevant false positives. The blue path was followed in spectral retrievals of Young et al. (2024) to categorize modern Earth, and the orange path for Archean Earth. Reproduced with permission from Young et al. (2024).-- astro-ph.IM

Astronomy & Telescopes, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Gaia - Planetary Perspectives, Habitable Zones, NASA Astrobiology Program, Status Report

Habitable Worlds Observatory (HWO): Living Worlds Community Working Group: The Search for Life on Potentially Habitable Exoplanets

by Keith CowingJanuary 16, 2026January 16, 2026

The discovery of a biosphere on another planet would transform how we view ourselves, and our planet Earth, in relation to the rest of the cosmos.

Left: Reflectance spectra of photosynthetic organisms on rock, mineral, and snow/ice abiotic surfaces with Archean, Proterozoic, and Modern atmospheric compositions (planetary spectra provided by Anna Grace Ulses, Univ. of Washington). The thick angled lines show the pigment ”edge” features in the spectrum. Right: Top: purple anoxygenic phototrophs with bacteriochlorophyll pigments absorbance and reflectance features at 805-880 nm at 15% planet coverage under an Archean atmosphere with 50% cloud cover. Middle: cyanobacterial microbial mat (oxygenic phototroph) with chlorophyll a absorption at 660-680 nm at 15% coverage under a Proterozoic atmosphere with 50% cloud cover. Note that the 3-D structure of the mat is effective at scattering light to create a ”red edge” feature similar to the vegetation red edge (VRE) shown in the bottom panel. Top two spectra provided by N. Parenteau, unpublished data. -- astro-ph.IM

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

Habitable Worlds Observatory Living Worlds Working Group: Surface Biosignatures on Potentially Habitable Exoplanets

by Keith CowingJanuary 15, 2026January 15, 2026

The Habitable Worlds Observatory (HWO) is the first NASA Astrophysics flagship mission with a key science goal of searching for signs of life on rocky habitable exoplanets beyond our solar […]

Habitable worlds - Grok via Astrobiology.com

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report

NASA Decadal Astrobiology Research and Exploration Strategy (NASA-DARES 2025) White Paper — Habitable Worlds Observatory Living Worlds Science Cases: Research Gaps and Needs

by Keith CowingJanuary 13, 2026January 16, 2026

Executive Summary: The Habitable Worlds Observatory (HWO) is the first astrophysics flagship mission with a key cross-divisional astrobiology science goal of searching for signs of life on rocky planets beyond […]

The Earth’s Lyman-α geocorona as observed from a distance of 0.1 au (panel a). The Earth’s exosphere is predominantly composed of neutral hydrogen, which escapes the lower atmosphere after being photodissociated into H and O atoms.95 Panel b represents the illumination of Earth by the Sun at the time of the observation. HWO may be capable of detecting this feature in Earth-like exoplanets, and we aim to make sure the its UV spectrograph is capable of doing so. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report

Ultraviolet Observations Of Atmospheric Escape In Exoplanets With The Habitable Worlds Observatory

by Keith CowingJanuary 13, 2026January 13, 2026

Among the many recommendations of the Decadal Survey on Astronomy and Astrophysics 2020, we found that a priority area of research is to pave the pathways towards finding and characterizing […]

Stellar SEDs for α Cen A (blue) and B (orange) binned to 1 ˚A. The SED of the Sun, scaled to a distance of 1.33 pc, from Woods et al. (2009) is shown in gray for comparison. Colored background regions show the various regions described in §5.2. The regions containing the reconstructed Lyα (1214–1217 ˚A, §5.2.4) and SISTINE detector gap (1270–1300 ˚A, §5.2.3) are not colored for clarity. The PHOENIX model extends to 107 ˚A but we have restricted the Y axis to 10−17 erg s−1 cm−2 ˚A −1 , again to aid visual clarity of features within the main spectra. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Radiation, Space Weather & Heliophysics, Status Report

Investigating the High-energy Radiation Environment of Planets in Sun-like Binary Systems

by Keith CowingJanuary 13, 2026January 13, 2026

Far-ultraviolet (FUV) radiation is a driving source of photochemistry in planetary atmospheres. Proper interpretation of atmospheric observations requires a full understanding of the radiation environment that a planet is exposed […]

Color-magnitude diagram showing the targets in the ExEP target list for HWO. The grey points represent a sample of stars within 100 pc taken from Gaia DR3. The cyan points indicate the locations of the Mamajek & Stapelfeldt (2024) targets that are in Gaia and have not been observed with speckle imaging. Orange squares highlight 80 ExEP list targets that have ‘Alopeke, Zorro, or NESSI observations. Red stars show the 27 targets that have been identified as members of stellar multiples by this work. The top axis provides approximate G − GRP values for F0V, G0V, K0V, and M0V stars. -- astro-ph.SR

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

Paving the Road to the Habitable Worlds Observatory with High-Resolution Imaging I: New and Archival Speckle Observations of Potential HWO Target Stars

by Keith CowingJanuary 12, 2026

One of the key goals of the Habitable Worlds Observatory (HWO) is to directly image about 25 potentially habitable exoplanets and determine their properties.

SEDs scaled to the EEID (top panel) and to the semi-major axis of each planet b (bottom panel). In the bottom panel the wavelength range is changed to expand the X-ray and ultraviolet range. The Sun at 1 au is overplotted in black for reference in both panels. Dashed lines show regions where proxies were used. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release, Stellar Cartography

The MUSCLES Extension for Atmospheric Transmission Spectroscopy: Spectral energy distributions For 20 Exoplanet Host Stars That JWST Observed in Cycle 1

by Keith CowingJanuary 9, 2026January 9, 2026

Correctly interpreting JWST spectra of close-in exoplanets requires a measurement of the X-ray and ultraviolet light that the planets receive from their host stars. Here we provide spectral energy distributions […]

Simulated image of a Solar System analog 30 light-years away, as captured by a large Infrared/Optical/Ultraviolet space telescope. STScI, NASA GSFC

Analog Studies, Astronomy & Telescopes, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release

NASA Selects Proposals To Advance The Habitable Worlds Observatory Astrobiology Mission Concept

by Keith CowingJanuary 5, 2026January 5, 2026

NASA announced Monday the selection of industry proposals to advance technologies for the agency’s Habitable Worlds Observatory concept – the first mission that would directly image Earth-like planets around stars […]

Plot of the Habitable Zone (HZ) completeness as a function of host star luminosity (in units of Solar luminosity) and distance (in parsecs). Here the AYO results are on the left and the EXOSIMS results are on the right. -- astro-ph.IM

Astronomy & Telescopes, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report

yieldplotlib: A Unified Library For Exoplanet Yield Code Visualizations

by Keith CowingDecember 26, 2025December 26, 2025

NASA’s next flagship observatory, the Habitable Worlds Observatory (HWO), aims to detect and characterize ~25 habitable zone planets.

Habitable Worlds Observatory

PyISH: Python Integral Field Spectroscopy Simulation for Habitable Worlds Observatory (HWO)

Habitable Worlds Observatory (HWO): Living Worlds Community Working Group: The Search for Life on Potentially Habitable Exoplanets

Habitable Worlds Observatory Living Worlds Working Group: Surface Biosignatures on Potentially Habitable Exoplanets

NASA Decadal Astrobiology Research and Exploration Strategy (NASA-DARES 2025) White Paper — Habitable Worlds Observatory Living Worlds Science Cases: Research Gaps and Needs

Ultraviolet Observations Of Atmospheric Escape In Exoplanets With The Habitable Worlds Observatory

Investigating the High-energy Radiation Environment of Planets in Sun-like Binary Systems

Paving the Road to the Habitable Worlds Observatory with High-Resolution Imaging I: New and Archival Speckle Observations of Potential HWO Target Stars

The MUSCLES Extension for Atmospheric Transmission Spectroscopy: Spectral energy distributions For 20 Exoplanet Host Stars That JWST Observed in Cycle 1

NASA Selects Proposals To Advance The Habitable Worlds Observatory Astrobiology Mission Concept

yieldplotlib: A Unified Library For Exoplanet Yield Code Visualizations

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

Excess Oxygen Stored In Deep Earth Magma May Help Explain How Earth’s Atmosphere Became Oxygen-rich

Using Nuclear Technology To Change How We Explore Icy Ocean Worlds: Examples From Nuclear Powered Mission Concept Designs

Radiation Limits On Amino Acid Preservation And Chiral Measurement At Oxia Planum

Tree of Life Program Targets Publication Of 200 Genome Notes Per Month