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Astronomers Successfully Predict Appearance of Supernova
schwit1 writes: For the first time ever astronomers have been able to predict and photograph the appearance of a supernova, its light focused by the gravitational lensing caused by a galaxy and the dark matter that surrounds it: "The NASA/ESA Hubble Space Telescope has captured the image of the first-ever predicted supernova explosion. The reappearance of the Refsdal supernova was calculated from different models of the galaxy cluster whose immense gravity is warping the supernova's light." What makes this significant is that the prediction models were based on the theory of gravitational lensing and required the presence of dark matter to work. That they worked and were successful in predicting the appearance of this gravitationally bent light (bent by the dark matter it passed through) is a very strong confirmation of both concepts.
They didn't predict that a supernova was about to happen. They'd already seen the supernova happening in its ghost image created by gravitational lensing. They predicted where another image of the supernova would turn up.
That it obeys the rules that dark matter would have to obey, and disobeys every theorem of mond that has ever been proposed.
Duh.
What else did you think a test and validation of a theory would incur? Cookies and presents for all?
We can ... in theory. The trouble is that our neutrino detectors aren't as sensitive as our optical telescopes. We can detect optical supernovae billions of light-years away, but we can only detect the neutrinos from a supernova within a few hundred thousand light-years.
The most recent supernova that was close enough to detect in neutrinos was in 1987 (SN1987A). Three detectors spotted neutrinos from it a few hours before the optical supernova, but they only noticed this coincidence after the fact.
We're a bit more savvy about it now, and I bet that, if there was another nearby supernova setting off multiple neutrino detectors, they'd notice the coincidence and send out an alert within a few minutes. They just need another nearby supernova (roughly, within our own galaxy), which happens once a decade or so.