by APOD Robot » Wed Nov 04, 2020 5:05 am
Fifty Gravitational Wave Events Illustrated
Explanation: Over fifty
gravitational wave events have now been detected. These events mark the distant, violent collisions of
two black holes, a black hole and a neutron star, or
two neutron stars. Most of the
50 events were detected in 2019 by the
LIGO gravitational wave detectors in the
USA and the
VIRGO detector in
Europe. In the
featured illustration summarizing the masses of the first
50 events, blue dots indicate higher-mass
black holes while orange dots denote lower-mass
neutron stars. Astrophysicists are
currently uncertain, though, about the
nature of events marked in white involving masses that appear to be in the middle -- between two and five solar masses. The
night sky in optical light is dominated by nearby and bright planets and stars that have been known since the dawn of humanity. In contrast, the
sky in gravitational waves is dominated by distant and dark
black holes that have only been known about for less than five years. This contrast is enlightening -- understanding the
gravitational wave sky is already reshaping humanity's knowledge not only of
star birth and death across the universe, but
properties of the universe itself.
[url=https://apod.nasa.gov/apod/ap201104.html] [img]https://apod.nasa.gov/apod/calendar/S_201104.jpg[/img] [size=150]Fifty Gravitational Wave Events Illustrated[/size][/url]
[b] Explanation: [/b] Over fifty [url=https://en.wikipedia.org/wiki/Gravitational_wave]gravitational wave[/url] events have now been detected. These events mark the distant, violent collisions of [url=https://apod.nasa.gov/apod/ap151020.html]two black holes[/url], a black hole and a neutron star, or [url=https://apod.nasa.gov/apod/ap171016.html]two neutron stars[/url]. Most of the [url=https://www.ligo.org/science/Publication-O3aCatalog/]50 events[/url] were detected in 2019 by the [url=https://apod.nasa.gov/apod/ap160207.html]LIGO gravitational wave detector[/url]s in the [url=https://en.wikipedia.org/wiki/United_States]USA[/url] and the [url=https://www.virgo-gw.eu/]VIRGO[/url] detector in [url=https://en.wikipedia.org/wiki/Europe]Europe[/url]. In the [url=https://www.ligo.org/science/Publication-O3aCatalog/images/Stellar_Graveyard_noerror_GWonly.png]featured illustration[/url] summarizing the masses of the first [url=https://www.aei.mpg.de/549420/dozens-of-new-gravitational-wave-events-in-six-months]50 events[/url], blue dots indicate higher-mass [url=https://www.nasa.gov/audience/forstudents/k-4/stories/nasa-knows/what-is-a-black-hole-k4.html]black holes[/url] while orange dots denote lower-mass [url=https://imagine.gsfc.nasa.gov/science/objects/neutron_stars1.html]neutron stars[/url]. Astrophysicists are [url=https://img1.wsimg.com/isteam/ip/f9769a59-a6b9-4e5e-8893-3ca270b404ce/EA145108-1AC0-4755-A73A-836CFD6EA571.jpeg]currently uncertain[/url], though, about the [url=https://apod.nasa.gov/apod/ap200908.html]nature of events[/url] marked in white involving masses that appear to be in the middle -- between two and five solar masses. The [url=https://apod.nasa.gov/apod/ap201021.html]night sky in optical light[/url] is dominated by nearby and bright planets and stars that have been known since the dawn of humanity. In contrast, the [url=https://apod.nasa.gov/apod/ap170928.html]sky in gravitational waves[/url] is dominated by distant and dark [url=https://en.wikipedia.org/wiki/Black_hole]black holes[/url] that have only been known about for less than five years. This contrast is enlightening -- understanding the [url=https://youtu.be/iphcyNWFD10]gravitational wave[/url] sky is already reshaping humanity's knowledge not only of [url=https://science.nasa.gov/astrophysics/focus-areas/how-do-stars-form-and-evolve]star[/url] birth and death across the universe, but [url=https://arxiv.org/abs/1908.06060]properties[/url] of the universe itself.
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