2/ I have, as usual, all the details in that linked article. But one thing I want to mention is the FRACKING UNBELIEVABLE resolution of this image. They are seeing details as small as 0.4 light years across on a galaxy over 5 *billion* light years away!
3/ We use angles to measure size on the sky. So the sky is 180° from horizon to horizon. The full Moon (did you see it last night?) is 1/2 a degree (0.5°) across.

The human eye can resolve objects down to about 1/60th of a degree. Anything smaller than that looks like a dot.
4/ We call 1/60th of a degree an arcminute, and each arcmin is further divided into 60 arcseconds (yes, this is based on time for historical reasons). So the Moon is 0.5° = 30 arcmin = 1800 arcsec wide in our sky.
5/ Still with me? OK, from the ground in general a telescope can resolve objects down to about 1 arcsec. Smaller than that and the motion of our atmosphere blurs them out. Usual special tech to account for that blurring we can drop that to 0.1 arcsec or so.
6/ Another technique allows us to combine telescopes at different locations. It can resolve MUCH smaller objects, down to a few thousandths of an arcsec. We call 1/1000th of an arcsecond a milliarcsecond.
7/ That’s with OPTICAL telescopes, the kind that see the same kind of light our eyes do. With radio telescopes we can do even better. Combining them from all over the planet allows vastly higher resolution. The technology is very advanced and takes a lot of work. But it’s doable.
8/ These new observations were made with that kind of array (the same one that made the black hole shadow image that wowed everyone last year).

This telescope has a resolution measured in MICRO arc seconds. Millionths of an arcsecond.

That’s staggering. INCREDIBLE.
9/ The new images have a resolution of about 20 microarcsec. That’s an angle so small it’s hard to relate to.

It’s like seeing an orange *sitting on the Moon*. Or standing in NYC and seeing the shape of a grain of sand in LA (ignoring Earth curvature there).

PHENOMENAL.
10/ So yeah, the Event Horizon Telescope, the name of this array of radio telescopes, is just mind-bendingly cool. And this isn’t even talking about *what* it actually saw.

And that’s… well, again, read the article. I’m blown away by this tech and this science. Amazing.
11/ Blobs of superheated material screaming away from a black hole at 99.5% the speed of light! Moving so rapidly that over the course of a few days the motion *was physically obvious in the images* even though it was occurring 50 billion trillion kilometers away! AIIEE AIIIEEEE!
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