DSS-43 boasts a pointing accuracy of 0.005 degrees (18 arc seconds)—which is important for ensuring that it is pointed directly at the receiver on a distant spacecraft. Voyager 2 broadcasts using a 23-watt radio. But by the time the signals traverse the multibillion-kilometer distance from the heliopause to Earth, their power has faded to a level 20 billion times weaker than what is needed to run a digital watch. Capturing every bit of the incident signals is crucial to gathering useful information from the transmissions.
The antenna has a transmitter capable of 400 kilowatts, with a beam width of 0.0038 degrees. Without the 1987 upgrade, signals sent from DSS-43 to a spacecraft venturing outside the solar system likely never would reach their target.
A cosmically interesting troubleshoot. But I'm not sure about their explanation. Why would the intermod disappear when they moved the Parkes Radio Telescope off of Proxima Centauri?
From https://www.thewrap.com/watch-crazy-footage-of-the-arecibo-observatory-collapse-goldeneye-video/ :
"Alas, over the 2010s it was battered by a series of severe, climate change-linked tropical storms and hurricanes, culminating in terrible damage inflicted by Hurricane Maria in 2017. Unfortunately the 2016 election led to a government unwilling to fund repairs. Though new sources of funding were cobbled together late in 2018, in late Nov. 2020 it was determined there was no way to safely repair the telescope and the National Science Foundation announced it would be decommissioned.
The decommissioning was supposed to proceed after NSF determined the safest possible method, but physics had other plans. So it is that on Dec. 4, the whole thing up and collapsed with almost no warning."
More info (from NSF):
https://www.nsf.gov/news/special_reports/arecibo/index.jsp
Here is a good 2017 article that discusses the electronic and mechanical arrangements at Arecibo, and the budget cuts it was facing. The article seems to almost predict the collapse:
Here is a comment from someone who worked there and heard the collapse:
Jonathan Friedman, who worked for 26 years as a senior research associate at the observatory and still lives near it, told the Associated Press news agency of the moment the telescope collapsed on Tuesday.
"It sounded like a rumble. I knew exactly what it was," he said. "I was screaming. Personally, I was out of control... I don't have words to express it. It's a very deep, terrible feeling." https://www.bbc.com/news/world-us-canada-55147973?fbclid=IwAR3RuwzTfJmqInrOOFB-nctknDzyB_VSr_qdNrjg9LbbxUnAbynKBv9stPQ
Here is an interesting WIKIpedia article on China's FAST dish, with comparisons to Arecibo:
This Hack-A-Day article explains the significance of 6EQUJ5 on the paper readout of the Big Ear radio telescope. It is a signal-to-noise readout.
The article also has interesting information about the radio telescope that was used.
I have on my shelf John Kraus W8JK's wonderful book "Big Ear Two -- Listening for Other Worlds." John Kraus is the guy who built the Big Ear. In a reminder of how new radio technology really is, Kraus got his start in radio as a ten year-old boy in 1920. He ripped the wire out of the ignition coil of a Model T Ford to make a tuning coil for a crystal radio. He took the earpiece out of the family telephone. His father gave him a chunk of Galena. He used the crystal radio to listen to the early broadcasts of WWJ in Detroit.
Not long ago we took the DISH satellite antenna off our roof. For a while I resisted pleas to put the big thing on the curb for pickup. I fantasized about using it for radio astronomy. In the end, I threw it away. I do have VHF/UHF aspirations, but being able to use that dish just seemed to be something in my distant future (if ever!).
But check out what David N2QG is doing with his dishes: He is listening to very distant spacecraft normally picked up only by NASA's Deep space network. Very cool. Truly inspirational.
Here are the links:
http://www.prutchi.com/2020/10/15/recap-of-x-band-dsn-activities-and-plans-for-the-future/
http://www.prutchi.com/wp-content/uploads/2020/10/DSN_Lessons-_Learned_N2QG.pdf
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