“We know it has to be at the outskirts of galaxies, but we don’t know what happens at the very centre,” says Valentina Crespi at the National University of La Plata (UNLP) in Argentina.

https://www.newscientist.com/article/2516077-is-our-galaxys-black-hole-actually-made-of-dark-matter/

#DarkMatter #BlackHole #Cosmology #NewScientist

#Masto

#CranfordTeague

“We know it has to be at the outskirts of galaxies, but we don’t know what happens at the very centre,” says Valentina Crespi at the National University of La Plata (UNLP) in Argentina.

https://www.newscientist.com/article/2516077-is-our-galaxys-black-hole-actually-made-of-dark-matter/

#DarkMatter #BlackHole #Cosmology #NewScientist

#Masto

#FickleFutures

“We know it has to be at the outskirts of galaxies, but we don’t know what happens at the very centre,” says Valentina Crespi at the National University of La Plata (UNLP) in Argentina.

https://www.newscientist.com/article/2516077-is-our-galaxys-black-hole-actually-made-of-dark-matter/

#DarkMatter #BlackHole #Cosmology #NewScientist

#Masto

#JasonSpeaks

Sonification of Every Gravitational Wave

Experience the cosmic symphony of gravitational waves!
This is a sonification of the first 90 confirmed gravitational wave detections, each the result of merging black holes and/or neutron stars. The extracted waveforms are synthesized and played as audio in the actual sequence they were discovered.

In the final seconds of each merger the black holes and neutron stars orbit each other faster and faster, reaching frequencies of 10s or 100s of times per second. These frequencies are within the human hearing range so we can listen to each merger unfold in real time. The increasing frequency of their spiralling dance creates a characteristic 'chirp' sound, marking the moment they finally merge. The time between each merger is compressed to let you experience the rhythm and variety of these remarkable cosmic collisions.

The first gravitational wave was detected in 2015 using 4km long laser interferometers called LIGO. The black hole merger that created this wave happened over a billion light years away, and hence over a billion year ago. Over the course of 3 observing runs, 89 more gravitational waves were detected, and at an increasing rate as the sensitivity of the detectors was improved. The 4th observing run started on May 24 2023 and holds the promise of even more astounding discoveries.

The black holes and neutron stars involved in these mergers are each 10s of kilometers across and orbit each other at a sizeable fraction of the speed of light. In the final few milliseconds the merger releases energy at a greater rate than all of the stars in the observable universe combined. This energy radiates as gravitational waves, carrying the signature of this cataclysmic event across the universe.

CREDIT
Video and sonification by SYSTEM Sounds (Matt Russo and Andrew Santaguida)
www.system-sounds.com

Background illustration by LIGO/Caltech/MIT/Sonoma State (Aurore Simonnet, http://auroresimonnet.com/)

Special thanks to Carl-Johan Haster

#space #blackhole #astrophysics #astrophotography #photography #astronomy #science #nature #NASA #ESA

2026 March 26

Black Holes and Neutron Stars: 218 Mergers and Counting
* Image Credit: Ryan Nowicki, Bill Smith & Karan Jani
https://ryannowicki.github.io/
https://www.fisk-vanderbilt-bridge.org/bill-smith
https://www.karanjani.com/
* Text: Cecilia Chirenti (NASA GSFC, UMCP, CRESST II)
https://science.gsfc.nasa.gov/sci/bio/cecilia.chirenti

Explanation:
What is the sound of two black holes merging in deep space? Sound waves don't propagate in vacuum, but gravitational waves do. In 2015 we were able to "hear" them for the first time and confirm one of Albert Einstein's theoretical predictions. Each square on the grid of the featured image represents one of the gravitational wave detections announced so far by the LIGO-VIRGO-KAGRA Collaboration. These plots show how the binary pair accelerates in their orbit around each other towards merger: the rising frequency effect is called a "chirp". Although there are significantly more neutron stars than black holes, most of the detections are binary black hole mergers. That happens because black holes are heavier and their signals are louder and can be seen farther away, resulting in more detections. These events are rare, and we don't expect to see one close by in our Galaxy any time soon. But they are happening continuously throughout the cosmos.
https://www.youtube.com/watch?v=QyDcTbR-kEA
https://www3.nasa.gov/specials/Quesst/science-of-sound.html
https://en.wikipedia.org/wiki/Gravitational_wave
https://apod.nasa.gov/apod/ap160211.html
https://www.nobelprize.org/prizes/physics/1921/einstein/biographical/
https://www.youtube.com/watch?v=gT1VwCTe_90
https://apod.nasa.gov/apod/ap211207.html
https://www.ligo.caltech.edu/image/ligo20250826a
https://www.ligo.caltech.edu/WA/news/ligo20260305
https://images.unsplash.com/photo-1533601017-dc61895e03c0
https://www.ligo.caltech.edu/
https://www.virgo-gw.eu/
https://gwcenter.icrr.u-tokyo.ac.jp/en/organization
https://gcn.nasa.gov/missions/lvk
https://apod.nasa.gov/apod/ap160212.html
https://www.ligo.caltech.edu/video/ligo20160615v2
https://science.nasa.gov/universe/neutron-stars-are-weird/
https://science.nasa.gov/universe/black-holes/
https://arxiv.org/abs/2508.18082
https://media.ligo.northwestern.edu/gallery/mass-plot
https://arxiv.org/pdf/2508.18083
https://science.nasa.gov/resource/the-milky-way-galaxy/
https://science.nasa.gov/resource/the-milky-way-galaxy/
https://science.nasa.gov/resource/the-milky-way-galaxy/

https://apod.nasa.gov/apod/fap/ap260326.html

#space #blackhole #astrophysics #astrophotography #photography #astronomy #science #nature #NASA #ESA