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|More from kilonova light & gravity reading||Oct 17, 2017 11:04 PM PDT | url | discuss | + share|
Added 1 new A* page:reported by NASA and discussed in this blog yesterday:|
- A new BBC article mentions that such dual observations give us another way to measure the expansion rate of the universe, since the shape and intensity of the signal tell you the distance to the event, and its speed relative to Earth can be determined by the redshift of the light emitted (I think that's what they mean by "analysing the light associated with the event", anyway). The universe's rate of expansion, symbolized by the Hubble Constant, in theory determines the ultimate fate of the universe, confirms or throws into question the Big Bang theory of the universe's creation, and is vastly important to fundamental theories of physics; it's precise value has been the subject of some debate for years, so having another way to measure it should ultimately help solve some of those big questions.
As the article describes, one widespread way to calculate the Hubble Constant has relied on stringing together estimated distance measurements to certain classes of stars, but the multiple measurements and assumptions required for those calculations can lead to problems in accuracy; the measurement made by combining gravity and light wave readings from a neutron star collision, on the other hand, can be done pretty much in one go, and thus, in theory, may prove more reliable.
- A reader tells me that, upon informing someone of yesterdays big space news, including the BBC's sound wave version of the gravitational waves generated by the neutron star collision, which converted into a surprisingly cool science-fiction type effect, that person aptly responded with The Pointer Sisters' "Neutron Dance." : D