[ExI] ...a long time ago in a galaxy far far away...

BillK pharos at gmail.com
Sat Jan 21 22:52:05 UTC 2023

On Sat, 21 Jan 2023 at 22:34, spike jones via extropy-chat
<extropy-chat at lists.extropy.org> wrote:
> This is really cool, but the way it is being reported in the popular press makes it sound to normal people like they are getting signals such as we get on our radios:
> https://spacecoastdaily.com/2023/01/radio-signal-detected-9-billion-light-years-away-from-earth-captured/
> We physics hipsters know that “radio signals” mean and know what the 21 cm hydrogen line is, but when they say “radio signals” from 9 billion years ago, far too many proles imagine stuff like Wolfman Jack saying things like “Hey there cats and dolls, put on your hipster shoes and get ready for back seat bingo with some BOSS rock and roll!”
> Still this is crazy cool the signals from that dang far out there.
> spike
> _______________________________________________

This article explains how this feat was achieved -
Neutral hydrogen emits light at a characteristic wavelength of 21
centimeters. But using neutral-hydrogen signals to study the early
universe is a tough task, as the long-wavelength, low-intensity
signals often get drowned out across vast cosmic distances. Until now,
the farthest 21 cm hydrogen signal detected was 4.4 billion
light-years away.
To find a signal at double the previous distance, the researchers
turned to an effect called gravitational lensing.
"In this specific case, the signal is bent by the presence of another
massive body, another galaxy, between the target and the observer,"
study co-author Nirupam Roy, an associate professor of physics at the
Indian Institute of Science, said in the statement. "This effectively
results in the magnification of the signal by a factor of 30, allowing
the telescope to pick it up."

Remarkable, indeed!


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