Active Galactic Nucleus Archives

Resolving The Extended Interstellar Medium Of Infrared Galaxies I. Polycyclic Aromatic Hydrocarbon Emission

by Keith CowingOctober 22, 2026October 22, 2026

[astro-ph.GA] We investigate spatial variations in polycyclic aromatic hydrocarbon (PAH) properties and photoelectric heating efficiency in 67 nearby luminous infrared galaxies from the Great Observatories All-sky LIRG Survey (GOALS).

Transition between different accretion regimes as shown by the shading and top labels. From left to right the panels show central AGN masses of 109, 108 and 107 𝑀⊙. The top row shows 𝑣frag = 1m s−1 and the bottom row shows 𝑣frag = 10 m−1 . The symbol 𝑚p gives the characteristic planetesimal mass, 𝑀HB is the transition mass between the Hill and the Bondi accretion regime, 𝑀BG is the transition mass between the Bondi and the geometric accretion regimes, and 𝑀p,iso is the pebble isolation mass. The transition between 2D and 3D accretion is also shown. In general, the objects will accrete in the 3D regime right after formation, except in the 1–10 pc range in the case 𝑣frag = 10 m/s, 𝑀SMBH = 109 𝑀⊙ (lower left). Accretion is also more efficient in the inner disk than in the outer disk, with a progression from Hill, Hill/Bondi, Bondi, and Bondi/Geometric as the central mass object decreases. The horizontal dotted black line is the hydrogen burning limit. -- astro-ph.EP

Astrogeology, Astronomy & Telescopes, Exoplanets, -moons, -comets, Status Report

Active Galactic Nucleus Tori: Potential Birthplace to Millions of Planets

by Keith CowingMay 23, 2026May 23, 2026

The outer regions of AGN disks have temperatures similar to those of circumstellar disks, permitting dust condensation. Therefore, planet formation and growth could be active in these dust tori through […]

Active Galactic Nucleus

Resolving The Extended Interstellar Medium Of Infrared Galaxies I. Polycyclic Aromatic Hydrocarbon Emission

Active Galactic Nucleus Tori: Potential Birthplace to Millions of Planets

Astrobiologist Dale Andersen’s Antarctic Field Report: 14 November 2026: Setting Up Lab and Dive Tents

Testing The Hypothesis, ‘Planetary Protection Is Expensive’ From The ESA Perspective

Tracing Galactic Dust Reddening with Polycyclic Aromatic Hydrocarbon Emission: SPHEREx Observations of the North Ecliptic Pole

Signatures of CH4 and NH3 in the Atmosphere of β Pictoris b

Hydrolyzed Hazes on Water-rich Exoplanets: Composition and Prebiotic Chemistry