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DausHMS t1_ja7h6ag wrote

Telescopes come in many shapes and sizes, with different types catering to different kind of observations, from radio all the way to gamma rays.


best_of_badgers t1_ja91pcr wrote

And gravitational wave! And neutrino! … except so far, our gravitational wave telescope has only two pixels.


jazzwhiz t1_ja9gx63 wrote

VIRGO is (sometimes) online so three pixels, but of varying quality.


Other-Weakness-9177 t1_ja9r9ac wrote

I don't know what this means but it made me think of me having only two to three brain cells. 😭


jazzwhiz t1_jaa01tf wrote

We can detect gravitational waves at a few points on the Earth. From this they can estimate the direction it came from by using timing and other information. The most sensitive experiment is called LIGO and is composed of two separate detectors, one in Washington state and one in Louisiana. The one in Louisiana is better than the one in Washington. There is also another experiment called VIRGO in Italy that is less sensitive but provides a third point to try to identify the direction of the gravitational wave burst event. See for example this plot which shows the region on the sky one real event is likely to have come from based on information from different sources. The green dashed region (HL) is what can be determined from the two LIGO detectors (Hanford and Livingston). The green solid region (HLV) is with VIRGO added in. The orange region is the directional information from a totally different experiment: the Fermi telescope in orbit around the Earth which measures gamma rays (photons). The gamma ray and gravitational wave signal happened at the same time and basically from the same direction so we're extremely confident that they are due to the same underlying physics.

The plot comes from here which has some code for playing around with these sorts of things. The paper for the plot is here.