Tag

Observational Astronomy

All articles tagged with #observational astronomy

science13 days ago•3 min saved

Third Dark-Matter-Free Galaxy Upends Galaxy Formation Theories

Yale-led researchers using Keck's KCWI measured the faint dwarf galaxy DF9, part of a 45-million-light-year linear chain with DF2 and DF4, to have a mass around 100 million solar masses that matches only its visible matter, showing no dark matter and supporting a violent-collision formation scenario that could strip dark matter from newborn galaxies; the finding strengthens the case for galaxies forming without dark-matter halos and prompts follow-up observations (including with the Mothra telescope) to search for residual gas and validate the proposed formation mechanism, with the study published June 16 in The Astrophysical Journal.

via Universe Today|

#dark-matter #dwarf-galaxies #galaxies

science2 years ago•11 min saved

"Using 'Echoes' to Study Black Holes in Detail"

Astrophysicist Erin Kara uses reverberation mapping to study supermassive black holes, measuring time delays in X-ray glows to reveal their immediate surroundings and understand their behavior. By tracking the gas and plasma near black holes, Kara can approximate their mass and reveal how they create extreme cosmic structures. Her work has provided unprecedented detail on black holes' feeding frenzies, earning her the 2022 Newton Lacy Pierce Prize. Kara discusses her research, the technique of reverberation mapping, and the questions she aims to address about black holes.

via Quanta Magazine|

#astrophysics #black-holes #observational-astronomy

astronomy2 years ago•3 min saved

Unveiling the Source of Intense Light in Supermassive Black Holes

New simulations have accurately replicated the entire sequence of a Tidal Disruption Event (TDE) from stellar disruption to the peak luminosity of the resulting flare, unveiling a previously unknown type of shockwave within TDEs and settling a longstanding debate about the energy source of the brightest phases in these events. This breakthrough paves the way for future studies to utilize TDE observations as a means to measure essential properties of black holes and potentially test Einstein's predictions in extreme gravitational environments, shedding new light on the mysteries of supermassive black holes.

via Phys.org|

#astronomy #observational-astronomy #shockwaves

astronomy2 years ago•4 min saved

"Scientists Witness Supernova Transforming into Black Hole, Confirming Link Between Massive Stars and Black Holes"

Scientists have observed the emergence of a compact object, possibly a neutron star or black hole, from a supernova explosion in a nearby galaxy, providing direct evidence of the stellar process that produces these dense objects. The supernova, named SN 2022jli, exhibited periodic changes in brightness, which were attributed to interactions between the remnant and its companion star. This marks the first time astronomers have observed the real-time emergence of a compact object from a supernova, advancing our understanding of stellar evolution and the formation of neutron stars and black holes.

via ScienceAlert|

#astronomy #black-hole #neutron-star

science-and-technology2 years ago•10 min saved

Revolutionizing Astronomy: The Game-Changing Extremely Large Telescope

The Extremely Large Telescope (ELT), set to be completed in 2028, will be the world's largest optical telescope, with a main mirror diameter of 39.3 meters. It will revolutionize observational astronomy by shedding light on various aspects of the universe, including the role of black holes, the effects of dark matter and dark energy, and the study of exoplanets. The ELT's enormous mirror will enable direct imaging of exoplanets and the analysis of their atmospheres, potentially revealing signs of alien life. Additionally, the telescope will provide insights into the early universe and help resolve mysteries surrounding the formation of stars and galaxies.

via The Economist|

#astronomy #exoplanets #extremely-large-telescope

astronomy2 years ago•3 min saved

Unintentional Discovery: Scientists Capture First-Ever Image of Black Hole's Swirling Ring

Scientists have accidentally measured the size of the disk of matter swirling around a supermassive black hole for the first time. The discovery, made while collecting data to confirm the presence of the accretion disk, could provide insights into the growth of black holes and the evolution of surrounding galaxies. The researchers used the Gemini Near-Infrared Spectrograph to detect a second double-peak emission from the outside edge of the accretion disk, allowing them to calculate its radius. This finding will help scientists observe the feeding process and inner structure of active galaxies, shedding light on the mysteries of supermassive black holes.

via Livescience.com|

#accretion-disk #astronomy #astrophysics

astronomy2 years ago•3 min saved

Unintentional Discovery: Scientists Capture First-Ever Image of Black Hole's Swirling Ring

via Yahoo Life|

#accretion-disks #astronomy #astrophysics

astronomy3 years ago•2 min saved

Ultra-diffuse local galaxies abound, say researchers.

Using cosmological simulations, an international team predicts that there may be up to 12 ultra-diffuse galaxies in the Local Group, a small cluster that currently contains approximately 60 known galaxies, including the Milky Way and Andromeda. Ultra-diffuse galaxies are faint and difficult to observe, but understanding their total number in the Local Group is crucial to our understanding of the cosmos. The discovery of these new galaxies could have far-reaching implications for our understanding of galaxy formation and evolution.

via Phys.org|

#astronomy #cosmological-simulations #galaxy-formation