Unintended Starlink signals hamper telescopes

Unexpected emissions from Starlink satellites are interfering with radio astronomy, a study from Curtin University has found.

The research showed that even in “radio quiet zones”, such as in outback Western Australia, electronics on board the satellites are emitting signals at “unexpected and unintended frequencies” that are brighter than natural objects in the sky.

These signals are picked up by sensitive radio telescopes like the under-construction Square Kilometre Array (SKA), Curtin University Professor Steven Tingay wrote in The Conversation.

“Even an extremely weak radio transmitter hundreds or thousands of kilometres away from the telescope appears as bright as the most powerful cosmic radio sources we see in the sky. So these signals represent a serious source of interference,” he said.

“The signals are an issue at the location where we tested them: the site in WA where construction has already begun for part of the biggest radio observatory ever conceived, the Square Kilometre Array (SKA). This project involves 16 countries, has been in progress for 30 years, and will cost billions of dollars over the next decade.

“Huge effort and expense has been invested in locating the SKA and other astronomy facilities a long way away from humans. But satellites present a new threat in space, which can’t be dodged.”

Speaking to Sky News, Professor Tingay stressed that the satellites are not breaking any international rules.

“The signals that we are seeing appear to be consistent with the regulations. Nonetheless, they’re a problem for doing astronomy,” he said.

“The regulatory approach to communications including between Earth and space, the evolution of those regulations occur at an almost glacial pace. So I think we’re in the situation where technology is really running ahead of the ability for regulation to keep pace.”

He added in The Conversation that his team has had a “very positive engagement” with SpaceX engineers working on the satellites.

“It is likely that the goodwill of satellite operators, and their willingness to mitigate the generation of these signals, is the key to solving the issue,” he said.

“In response to earlier criticisms, SpaceX has made improvements to the amount of sunlight Starlink satellites reflect, making them one-twelfth as bright in visible light as they used to be.

“We estimate emissions in radio wavelengths will need to be reduced by a factor of a thousand or more to avoid significant interference with radio astronomy.”

By: Jake Nelson

From: https://www.spaceconnectonline.com.au/satellites/6037-unintended-starlink-signals-interfere-with-radio-telescopes