Second Cable Fails at Arecibo, Causing Even More Damage to Famed SETI Dish

Second Cable Fails at Arecibo, Causing Even More Damage to Famed SETI Dish
Damage to the dish as a result of the August cable failure. (Image: UCF Today)

Another cable has fallen onto the reflector dish at the Arecibo Observatory in Puerto Rico, in yet another frustrating setback for this beloved facility.

The main support cable of the Arecibo Observatory failed and fell onto the dish below at 7:30 p.m. Puerto Rico time on Friday November 6, reports UFC Today. The extent of the damage is not yet known, but the dish was damaged further, as were some nearby cables. No one was hurt, but a safety zone has been set up around the facility as a precaution. With two failed support cables in three months, it’s imperative that response teams now find a way to stabilise the structure.

File photo showing the observatory as it appeared in the spring of 2019.  (Photo: UCF Today) File photo showing the observatory as it appeared in the spring of 2019. (Photo: UCF Today)

The first incident happened on August 10, when a 3-inch-thick auxiliary cable fell onto the observatory’s main reflector dish, creating a 3.05 m-long gash. The reason for the failure has yet to be determined, but the auxiliary cable appears to have slipped out from its socket. This doesn’t appear to be the case for the main cable, which simply snapped, possibly a result of the extra weight imposed on the remaining cables, according to observatory officials. As UFC Today reports, officials were aware of broken wires on the main cable, and engineers were scheduled to make emergency repairs this week.

Like the failed auxiliary cable, the main cable connects to the main support tower. The incident from this past August also resulted in damage to the Gregorian Dome and the platform used to access the dome. The facility at Arecibo is managed by the University of Central Florida on behalf of the U.S. National Science Foundation, under a cooperative agreement with Universidad Ana G. Méndez and Yang Enterprises.

Here’s what observatory director Francisco Cordova told UFC today in response to this latest incident:

“This is certainly not what we wanted to see, but the important thing is that no one got hurt. We have been thoughtful in our evaluation and prioritised safety in planning for repairs that were supposed to begin Tuesday. Now this. There is much uncertainty until we can stabilise the structure. It has our full attention. We are evaluating the situation with our experts and hope to have more to share soon.”

The response team will try to reduce the tension in the existing cables by installing steel reinforcements — something they’d like to do as soon as possible. The team is also hoping to expedite procurement of two new support cables currently on order. These plans could evolve over the next few days as the situation is assessed further.

Progress at Arecibo has been slow since the August incident, as officials struggle to pinpoint the cause of the auxiliary cable failure. The failed socket, for example, was sent to NASA for a forensic analysis. Arecibo officials had previously asked the National Science Foundation for funds needed to make temporary repairs, but the projected cost of the repairs is not yet known. The observatory, which was built in the 1960s, has a long history of fiscal uncertainty, in addition to enduring damage from hurricanes and earthquakes.

We reached out to Arecibo to learn more about the recent damage and other details, and we’ll update this post should we hear back.

This is all so very sad, as Arecibo hosts some very valuable scientific work. In addition to contributing to the search for extraterrestrial intelligence (SETI), the dish is used for radio astronomy and atmospheric and planetary science. Importantly, the observatory is also on the lookout for potentially hazardous near-Earth objects.