Which is more difficult:
(1) Putting a telescope in space
(2) Focusing and detecting very high energy neutrinos
This is especially the case when photons will have, what, 15 orders of magnitude less energy than the neutrinos?
(1) Putting a telescope in space
(2) Focusing and detecting very high energy neutrinos
This is especially the case when photons will have, what, 15 orders of magnitude less energy than the neutrinos?
This is why I always search for my keys under the streetlamp, even though I dropped them in the unlit field nearby.
That said, putting a telescope in space is easy; we've done it several times...
But, can we filter photons intentionally sent from some far off solar system out of the stream of photons coming from their local star?
It would be VASTLY easier than using neutrinos.