SpaceX satellite leaked radio waves. Astronomers are worried

SpaceX satellite leaked radio waves

On July 5, 2023, astronomers from various institutions announced that their new research had detected «unintended electromagnetic radiation» emitted by electronic devices on the planet’s surface. ships of the controversial Starlink satellites. They say this measurable leak from satellites — which make up SpaceX’s massive constellations of satellites — may have interfered with radio astronomy.

These scientists are working under the auspices of the International Astronomical Union (IAU) Center for the Protection of the Dark and Quiet Sky from Constellation Constellation Interference (CPS).

Scientists confirmed radiation leaks in observations made with the LOFAR telescope, a low-frequency radio array in the Netherlands.

Reviewed magazine Astronomy and Astrophysics accepted the study for publication on May 12, 2023.

Pretty proud of my answer to this Elon fanboy in a Reddit thread about major constellation effects on radio astronomy pic.twitter.com/GNZppDoJ5c

– Yvette Cendes (@whereisyvette) July 11, 2023

Musk’s SpaceX Starlink Satellite

For the study, scientists observed 68 Starlink satellites. While the researchers focused on the Starlink satellites because they dominate the category of man-made objects in orbit around Earth, they realized that there are other large constellations of satellites. Their statement said:

The authors hope to detect similar unintended emissions from other low-Earth-orbiting satellites, and further measurement work is planned to focus on other constellations of satellites.

Lead author Federico Di Vruno of the IAU said:

This study represents the latest attempt to better understand the impact of satellite constellations on radio astronomy. Previous workshops on Dark and Quiet Sky have hypothesized this radiation, and our observations confirm that it is measurable.

Listen to the sky

Radio astronomers detect weak radio signals from the sky to learn more about dying stars, the black hole at the center of our galaxy, etc. On Earth, radio astronomers are always faced with man-made radio signals, and as a result they often build their telescopes in locations far from interference. In fact, there are even plans to build a radio telescope in a crater on the far side of the moon.

But it is clearer that radio telescopes on Earth are facing an increasing problem of satellite interference. While all astronomical observatories must deal with the problem of satellites passing through the field of view of their instruments, radio astronomers say the problem is particularly acute for them.

The radio signal of a satellite is many, much stronger than the faint background sources that radio astronomers study. And a satellite doesn’t have to pass directly in front of a study object to cause interference. Satellite sources in the “peripheral line of sight” of radio telescopes also cause interference.

But there is much more. Astronomers explain:

With thousands of satellites in low Earth orbit, any radio telescope will have multiple signaling satellites in its line of sight at any given time. It is expected that the main source of interest from the satellite constellations will be their planned transmission of communications to and from Earth.

Also, radio telescopes don’t just look at dim light in the night. They are looking up at the sky 24/7. So satellites are an issue every hour of the day, not just at dusk.

And now they have confirmed there is a measurable electromagnetic radiation leak from the satellites.

How to prevent satellite radiation leakage

On Earth, the law regulates how much radiation from a device can cause interference to a nearby device. But for satellites, this type of radiation is not subject to any international law. Cees Bassa, co-author from ASTRON, said:

With LOFAR, we detected radiation between 110 and 188 MHz from 47 of the 68 observed satellites. This frequency range includes a protected frequency band between 150.05 and 153 MHz specifically allocated by the International Telecommunication Union (ITU) for radio astronomy.

So, in space, satellite owners don’t break any laws. But astronomers say they want to work with satellite operators and regulators to address this impact. In fact, astronomers have worked with SpaceX. The aerospace company has introduced several mitigation devices for their next generation of satellites. Co-author Gyula Józsa of the Max Planck Institute for Radio Astronomy and Rhodes University said:

We believe that early recognition of this situation will give astronomical and major constellation operators the opportunity to work together to proactively mitigate technical measures, in parallel with discussions. necessary to develop appropriate regulations.

The future of expanding satellite constellations

According to the IAU’s Center for the Protection of Dark and Quiet Sky, there are currently 4,276 active constellation satellites orbiting the Earth. While that may sound like a lot, there are 427,171 constellation satellites planned. So the problem will only get worse. Benjamin Winkel from the Max Planck Institute for Radio Astronomy said:

Our simulations show that the larger the constellation, the more important this effect becomes when the radiation from all the satellites is combined. This worries us not only about the existing constellations, but even more about the planned ones…and also about the lack of clear regulation to protect the radio astronomy bands. from unwanted radiation.

Here’s hoping the budding teamwork between scientists and satellite operators will be a bright step towards darker and quieter skies.

The bottom line: A new study confirms that 68 satellites are leaking radio waves that could harm radio astronomers’ observations of the universe. Astronomers are worried.

Source: Unintended electromagnetic radiation from Starlink satellites detected with LOFAR between 110 and 188 MHz

Long live IAU