Astronomers Watch a Supernova and See Reruns

nytimes.com

142 points·fspeech··6 comments

This the most exciting astronomical development I've heard about for several years. One gets the impression that there might be perspectives like this all over the place, much as the discovery of the first few exoplanets was followed by an avalanche of others.

Am I right in thinking that the temporal offsets of the gravitational lensing allow for a sort of controlled experiment, eg where astronomers study the oldest image of the supernova and form hypotheses about its development, then test those hypotheses against the later ones?

Not quite, I think. The supernova is more used to study the dark matter lens, which cannot be seen directly. Seeing the supernova being lensed by different parts of the galaxy cluster will allow them to map the dark matter profile of the galaxy and study how it's distributed.

I used to think about this: Would it be possible to find a configuration of galaxies with enough mass to bend light from one point on earth back to another point on earth? If we could do that, we actually look at an older timestamp of earth.

Yes, we'd need a reeeeally powerful telescope, but maybe we could find that in another configuration of galaxies as well.

Yes, it is possible, but we'd need better telescopes. This post has a pretty good analysis: http://rein.pk/gravitational-lensing-to-observe-ancient-eart...

The whole series of videos about various astronomic subjects is extremely well done. The music and narration of Dennis Overbye remind me of the old Carl Sagan movies, this time made for the newer generation, with a shorter attention span.

If we had powerful enough telescope that we could see a civilization growing up 1000 light years away we could record it and provide it as a gift for when we finally meet. Or maybe there is someone out there doing that for us.

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