Arecibo radio telescope to be de-comissioned

[Rick]

America's largest radio telescope blind after falling cable slashes 100-foot gash in reflector dish

On Tuesday, the University of Central Florida, which helps manage the National Science Foundation facility, said that on Monday, around 02:45 local time, a three-inch auxiliary cable supporting a metal platform above the observatory broke free and fell.

In addition to the damage to the main reflector, the cable's collapse also broke six to eight panels on the Gregorian Dome, a structure above the dish that houses sub-reflectors for focusing radiation, and twisted the platform providing access to the dome.

More: https://www.theregister.com/2020/08/12/arecibo_observatory_damaged/

[Rick]

NSF to decommission Arecibo radio telescope

The National Science Foundation announced Nov. 19 it will perform a "controlled decommissioning" of the giant radio telescope at the Arecibo Observatory in Puerto Rico, citing recent damage that made it unsafe to operate or even repair.

More: https://spacenews.com/nsf-to-decommission-arecibo-radio-telescope/

[Rick]

NSF begins planning for decommissioning of Arecibo Observatory's 305-meter telescope due to safety concerns

Following a review of engineering assessments that found damage to the Arecibo Observatory cannot be stabilized without risk to construction workers and staff at the facility, the U.S. National Science Foundation will begin plans to decommission the 305-meter telescope, which for 57 years has served as a world-class resource for radio astronomy, planetary, solar system and geospace research.

The decision comes after NSF evaluated multiple assessments by independent engineering companies that found the telescope structure is in danger of a catastrophic failure and its cables may no longer be capable of carrying the loads they were designed to support. Furthermore, several assessments stated that any attempts at repairs could put workers in potentially life-threatening danger. Even in the event of repairs going forward, engineers found that the structure would likely present long-term stability issues.

More: https://www.nsf.gov/news/news_summ.jsp?cntn_id=301674

[Rick]

Adiós Arecibo Observatory: America's largest radio telescope faces explosive end after over 50 years of service

The Arecibo Observatory, America's largest radio telescope, is to be blown up after the National Science Foundation decided recent damage has left it too dangerous to repair.

"NSF prioritizes the safety of workers, Arecibo Observatory's staff and visitors, which makes this decision necessary, although unfortunate," its director, Sethuraman Panchanathan, said in a statement on Thursday.

"For nearly six decades, the Arecibo Observatory has served as a beacon for breakthrough science and what a partnership with a community can look like. While this is a profound change, we will be looking for ways to assist the scientific community and maintain that strong relationship with the people of Puerto Rico."

More: https://www.theregister.com/2020/11/19/arecibo_telescope_decommissioned/

[Rick]

Arecibo Observatory brings forward 'controlled demolition' plans by collapsing all by itself

The Arecibo Observatory appears to have been destroyed with the collapse of the platform previously suspended above the giant dish.

Before and after shots of the facility show the triangular platform, which had hung over the dish, is no longer in place.

More: https://www.theregister.com/2020/12/01/arecibo_collapse/

[Rick]

Puerto Rico: Iconic Arecibo Observatory telescope collapses

A huge radio telescope in Puerto Rico has collapsed after decades of astronomical discoveries.

The US National Science Foundation (NSF) said the telescope's 900-ton instrument platform fell onto a reflector dish some 450ft (137m) below.

It came just weeks after officials announced that the telescope would be dismantled amid safety fears, following damage to its support system.

More: https://www.bbc.co.uk/news/world-us-canada-55147973

[AndrewRamsay]

There is an interesting article in this week's Economist about the background to the building and use of the Arecibo telescope.  It seems it was used to send a message into space - and it is now 46 light years away and can't be recalled!  See https://www.economist.com/science-and-technology/2020/11/25/with-the-death-of-arecibo-an-era-ends-for-radio-astronomy

[Carole]

They were right to be cautious about sending staff in to fix it, there could have been a serious accident.

Carole

[Rick]

The big loss is in its transmitting capability. Interferometer arrays aren't much good for transmitting, so only something like Arecibo was big enough to be used for things like radar imaging of asteroids. There is that new big dish in China, but not much else.

There are some videos of the collapse happening.

[Mac]

Drone footage of the collapse, it just happened to be checking the cables as they failed. 

https://www.youtube.com/watch?v=u34uwFOCM-4

Mac.

[Rick]

Interesting shots of the event. Neither camera was in a place anyone would have wanted to be anywhere close!

[Rick]

Here's a fairly detailed analysis of those videos: https://www.youtube.com/watch?v=59WQIRvezzI