For what it's worth, this is on the Arecibo website:
Click image for source page.
Posted on 01/11/2018 7:44:14 PM PST by MtnClimber
n Christmas Eve 2016, Andrew Seymour, an astronomer at the Arecibo Observatory in Puerto Rico, kissed his 4-year-old daughter, Cora Lee, goodnight, telling her he was off to track Santa. He walked to the well-worn telescope, occasionally passing revelers riding horses through the empty streets — a common sight in Arecibo during the holidays. Sometimes a lonely firework would light up in the distance. Close to midnight, he nodded to a guard and entered the nearly empty complex.
The radio dish was on a break from its regular schedule, so Seymour decided to test out new hardware that he and his colleagues had been working on. Soon after he began recording his observations, an extremely powerful radio source, 3 billion light-years away, decided to say hello. Seymour didn’t find Santa that Christmas, but rather an unexpected twist in the tale of one of the most mysterious objects in the cosmos.
The object that Seymour caught that night was the only known repeating fast radio burst (FRB), an ultra-brief flash of energy that flickers on and off at uneven intervals. Astronomers had been debating what might be causing the mysterious repeater, officially called FRB 121102 and unofficially the “Spitler burst,” after the astronomer who discovered it.
In the weeks following that Christmas detection, Arecibo registered 15 more bursts from this one source. These flashes were the highest frequency FRBs ever captured at the time, a measurement made possible by the hardware Seymour and his team had just installed. Based on the new information, the scientists have concluded in a study released today in the journal Nature that whatever object is creating the bursts, it must be in a very odd and extreme cosmic neighborhood, something akin to the environment surrounding a black hole with a mass of more than 10,000 suns.
(Excerpt) Read more at quantamagazine.org ...
Lucky to spot it with a parabolic reflector built into the earth that can’t be pointed.
Extreme Cosmic Neighbourhood is a great name for a rock band.
Actually it CAN be pointed.
It is pointed by manipulating the feed-point/focus-point to look at only part of the reflective parabola below.
It is true that the only time the entire reflector can be utilized is when the target is directly in front.
The farther the target gets from 90deg the lower the gain.
With a reflector that large the movement of the feed where there is gain to point off a bit must be only a few tenths of a degree, depending on frequency.
To be technically precise the reflector is spherical and not perfectly parabolic.
This in fact allows use of the reflector far away from 90deg without any astigmatic aberrations...just a diminishing gain the farther off axis.
A simple parabolic satellite dish can in fact be used several degrees off-center. This has been done for a long time with small ground-based antennae, i.e. systems for home reception of TV signals. They do suffer from a bit of astigmatic loss.
1. We do not know what it really is.
2. The energy of these bursts are beyond belief.
Okay. This is officially the poindexter thread.
Making it a good place to learn stuff. I knew that the Aricebo dish could be directed, I just didn’t know that it was by that much.
Thanks for posting.
That’s an excellent science article.
For what it's worth, this is on the Arecibo website:
Click image for source page.
Thanks for that link.
It’s still broken though - I couldn’t get it to move even 1 degree!
I do pick up some small knowledge that way.
Carry on, eggheads.
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