Tag: #astronomy

Fermi Releases Most Sensitive Low‑Energy Gamma‑Ray Catalog, Identifying 60 New Sources

Fermi-LAT's 2FLE catalog lists 450 sources between 20–200 MeV, including 60 previously unseen gamma-ray sources, helping close the MeV gap.

#astronomy, #gammarays, #fermilat, #astrophysics

Webb Pins Most Distant Localized Fast Radio Burst to Tiny Star‑Forming Dwarf Galaxy

James Webb identified the host and redshift (z=2.148) of FRB 20240304B — the most distant localized FRB — linking it to a tiny, star-forming dwarf galaxy.

#frb, #jameswebb, #astronomy, #magnetars

Study finds eight ultramassive (>10 billion M⊙) black holes in brightest cluster galaxies

Accepted ApJ paper reports eight new direct detections of ultramassive black holes (>10 billion M⊙) in brightest cluster galaxies; core size may predict mass better than velocity dispersion.

#astronomy, #blackholes, #galaxies, #astrophysics

Gaia astrometry suggests hidden fifth companion in HR 8799 system

Gaia and archival data point to a possible 10–14 Jupiter-mass object 2–3 au from HR 8799, filling a long-standing inner detection gap.

#exoplanets, #gaia, #hr8799, #astronomy

Preprint claims first direct auroral radio detection and magnetic-field measurement for exoplanet β Pictoris b

Unreviewed arXiv preprint reports MeerKAT detections of auroral radio bursts from β Pictoris b and infers a ≳1.25 kG magnetic field; confirmation needed.

#exoplanets, #astronomy, #radioastronomy, #magneticfields

Preprint: Strong helium outflow detected on sub‑Neptune GJ 3090b could strip its gas in ~300 million years

An arXiv preprint reports a strong metastable-helium signal from sub‑Neptune GJ 3090b, implying rapid photoevaporative loss that could strip its H‑He envelope in ~300 million years.

#exoplanets, #astronomy, #helium, #photoevaporation

Study of eROSITA clusters gives first constraints on Early Dark Energy; joint fit suggests H0 ≈ 71 km/s/Mpc

eROSITA cluster counts yield first cluster-based constraints on Early Dark Energy; combined with CMB and BAO the fit finds f_EDE≈0.10 and H0≈71.4±1.4 km/s/Mpc.

#astronomy, #cosmology, #erosita, #hubbletension

Roman Space Telescope Begins Three-Month Journey to Sun‑Earth L2 After Aug. 30 Launch

Launched Aug. 30, NASA’s Nancy Grace Roman Telescope is en route to Sun‑Earth L2 to map galaxies, probe dark energy and hunt exoplanets with a wide-field infrared camera.

#space, #nasa, #telescope, #astronomy, #roman

Deeper X‑ray and JWST Data Cast Doubt on Claimed Black Hole in Galaxy UHZ1

Deep Chandra and JWST reanalysis finds no solid X‑ray or mid‑IR evidence that galaxy UHZ1 (z=10.05) hosts the luminous, obscured black hole claimed in 2023.

#astronomy, #black-holes, #jwst, #chandra

Deep JWST spectrum of GN-z11 shows very massive stars and resolved Lyα at z=10.6

New JWST spectroscopy of GN‑z11 (z=10.6) finds signatures of very massive stars, strong winds and a redshifted Lyα wing that may let Lyα escape the early universe.

#astronomy, #jameswebb, #gnz11, #reionization

ALMA resolves thin molecular filaments near HESS J1023-575; preprint suggests possible microquasar jet traces

An arXiv preprint shows ALMA-resolved thin filaments near HESS J1023-575 and proposes they may be remnants of an ancient microquasar jet.

#astronomy, #cosmicrays, #alma, #microquasar

NASA’s Astronomy Picture of the Day Features Zaragoza Photo of Aug. 12 Total Solar Eclipse

NASA’s Astronomy Picture of the Day spotlights a Zaragoza photo capturing the fleeting Aug. 12 total solar eclipse over the Cathedral-Basilica and Ebro River.

#solar-eclipse, #spain, #astronomy, #apod

Preprint: FRB–Planck analysis suggests about half of the missing baryons sit in warm-hot intergalactic gas

A new preprint finds a CHIME FRB–Planck cross-correlation implying roughly half of ordinary baryons may lie in the warm-hot intergalactic medium; result awaits review.

#astronomy, #frb, #cosmology, #whim

H.E.S.S. detects no gamma-ray line from Galactic Centre, but reaches thermal Higgsino benchmark

H.E.S.S.'s deepest search found no gamma-ray line from the Galactic Centre but sets the strongest limits yet, probing thermal Higgsino models.

#darkmatter, #astronomy, #gamma-rays, #astrophysics

Spent SpaceX Falcon 9 Upper Stage Predicted to Strike Moon; Plume Might Be Visible

A spent SpaceX Falcon 9 upper stage is predicted to strike the Moon Aug. 5; models suggest a sunlight-lit debris plume might be briefly visible from Earth.

#space, #moon, #spacex, #astronomy