APOD: 2026 March 26 Б
26.03.2026

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.

Two Black Holes Merge
12.02.2016

Just press play to watch two black holes merge. Inspired by the first direct detection of gravitational waves by LIGO, this simulation video plays in slow motion but would take about one third of a second if run in real time.

A Road to the Stars
15.03.2022

Pictured -- a very scenic road to the stars. The road approaches La Silla Observatory in Chile, with the ESO's 3.6-meter telescope just up ahead. To the left are some futuristic-looking support structures...

APOD: 2023 June 29 Б A Message from the Gravitational Universe
29.06.2023

Monitoring 68 pulsars with very large radio telescopes, the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has uncovered evidence for the gravitational wave (GW) background by carefully measuring slight shifts in the arrival times of pulses. These shifts are correlated between different pulsars in a way that indicates that they are caused by GWs.

Simulation: Two Black Holes Merge
14.04.2019

Sit back and watch two black holes merge. Inspired by the first direct detection of gravitational waves in 2015, this simulation video plays in slow motion but would take about one third of a second if run in real time.

GW200115: Simulation of a Black Hole Merging with a Neutron Star
14.07.2021

What happens when a black hole destroys a neutron star? Analyses indicate that just such an event created gravitational wave event GW200115, detected in 2020 January by LIGO and Virgo observatories. To better understand the unusual event, the featured visualization was created from a computer simulation.

GW190521: Unexpected Black Holes Collide
8.09.2020

How do black holes like this form? The two black holes that spiraled together to produce the gravitational wave event GW190521 were not only the most massive black holes ever seen by LIGO and VIRGO so far, their masses -- 66 and 85 solar masses -- were unprecedented and unexpected.

Unusual Signal Suggests Neutron Star Destroyed by Black Hole
3.09.2019

What created this unusual explosion? Three weeks ago, gravitational wave detectors in the USA and Europe -- the LIGO and Virgo detectors -- detected a burst of gravitational radiation that had the oscillating pattern expected when a black hole destroys a neutron star.

Simulation: Two Black Holes Merge
10.05.2024

Relax and watch two black holes merge. Inspired by the first direct detection of gravitational waves in 2015, this simulation plays in slow motion but would take about one third of a second if run in real time. Set on a cosmic stage, the black holes are posed in front of stars, gas, and dust.