Highlights
- Solar storms can affect satellites in a number of ways.
- Recent solar storms have reportedly knocked dozens of satellites out of skies above, getting them toasted upon re-entry to the Earth's atmosphere.
- Heads up, skywatchers: fresh data from NASA models suggests a solar storm sparked by the recent M9.7 flare might reach Earth around noon on June 11.
- This could disrupt communications for aviators, high-frequency (HF) and very-high-frequency (VHF) radio operators, and GPS users, especially in high-latitude regions.
Forget the calm yellow ball of blinding light you see in the sky on a postcard-perfect sunrise or sunset. Our sun is really a giant ball of churning hot gas with a magnetic field.
Now, imagine a bubble of superheated gas, a billion tonnes strong, flying at a million miles per hour. That’s a solar flare. There are no warning signs for these bursts. Because they’re so fast, we don't get a heads-up before they hit. It's causing concern.
• Sun bursts: Imagine a super bright flash of light, that’s a solar flare. These travel super fast, like turning on a light switch – they hit us right away.
• Sun clouds: These are giant clouds filled with energetic particles, called coronal mass ejections (CMEs). They move slower, taking days to reach Earth.
Risks to satellites
The risks, especially to communication satellites, are real. On December 16, 2023, a massive solar flare disrupted radio signals on Earth.
These flares happen more often when the sun's magnetic field is extra knotted up, which peaks every 11 years or so, according to astronomers.
Earlier, on February 8, 2022, SpaceX reported that it “lost” 40 satellites after a “geomagnetic storm” a day after launch. “Onboard GPS suggests the escalation speed and severity of the storm caused atmospheric drag to increase up to 50% higher than during previous launches,” SpaceX stated then.
Its engineers tried to put the satellites into a “safe mode”, turning them to fly edge-on to minimise drag. But the drag was so strong that it stopped the satellites ever getting out of that “safe mode” and go back to the desired orbit.
40
Number of satellites lost by Starlink network following 'geomagnetic storm'Those 40 satellites, 80 per cent of the batch deployed in low-earth orbit, were burned up on atmospheric re-entry after progressive orbital “decay” following the solar burst (as of May 2024, there were 6,078 Starlink satellites in orbit, according to a tracking site.)
Strong solar bursts can disrupt not only satellites but also power grids. In extreme cases, they could even cause widespread blackouts.
Scientists are constantly monitoring the Sun for solar activity and develop ways to predict and mitigate the effects of solar storms.
3,409
number of known “inactive” satellites orbiting the earth (Source: UN Office for Outer Space Affairs)It is currently unknown how many satellites were hit or damaged by recent solar storms. In addition to the February incident, SpaceX also admitted on May 11, 2024 that its services had been “degraded”. CEO Elon Musk wrote on X that its satellites were “under a lot of pressure, but holding up so far.”
Of the 8,261 satellites orbiting the Earth, only 4,852 satellites are active (as of December 2021).
(Sources: Index of Objects Launched into Outer Space, UN Office for Outer Space Affairs; Union of Concerned Scientists, UCS)
Flares can fry them
In general, satellites will continue to be at risk from solar flares or solar storms. This is because flares can fry or slow down spacecraft around the earth.
Communication satellites, GPS satellites, even the International Space Station (ISS) can be affected depending on the severity of the flare.
Scientists are studying these effects to protect our power grids and help satellite operators protect their equipment, and astronauts can avoid spacewalks during such bad storms.
Because these particles can mess with Earth's upper atmosphere, they can cause surges in power lines that might damage equipment. Scientists are studying these effects to protect our power grids and help satellite operators protect their equipment, and astronauts can avoid spacewalks during such bad storms.
Here's a breakdown:
Communication satellites
These are particularly susceptible to damage from energetic particles, which can disrupt their ability to transmit signals. NOAA Solar Energetic Particles (energetic protons) can also penetrate satellite electronics – and cause electrical failure.
These energetic particles also block radio communications at high latitudes during solar storms.
GPS satellites
The puffed-up atmosphere caused by flares can interfere with radio signals, affecting the accuracy of GPS readings. Because these particles can mess with Earth's upper atmosphere, they can cause surges in power lines that might damage equipment. Scientists are studying these effects to protect our power grids. The charged particles can also disrupt radio signals and mess with GPS accuracy for a while.
Spacecraft in orbit
Even astronauts on the ISS need to take shelter during strong flares to avoid radiation exposure.
Earth's magnetic shield
Luckily, Earth has a magnetic field that helps to deflect most of the particles and radiation from solar storms.
This magnetic field channels some of the charged particles towards the poles, creating the beautiful auroras (northern and southern lights).
However, solar storms can and do cause problems for our technology. Strong solar bursts can disrupt satellites, power grids, and GPS systems. In extreme cases, they could even cause widespread blackouts. Scientists are constantly monitoring the Sun for solar activity and have developed ways to predict and mitigate the effects of solar storms.
Solar flares can mess with satellites in a couple of ways:
Charged particles
Solar flares unleash a burst of energetic particles. These can directly damage the electronics on a satellite, causing malfunctions or even complete failure. Like a tiny space zap.
Supercharged atmosphere
The ultraviolet radiation from flares heats up the Earth's upper atmosphere, making it “expand”, or puff up. This “expansion” event increases the drag on Earth-orbiting satellites, thus reducing their lifetime in orbit.
Because a satellite in orbit moves faster when it is close to the planet or other body that it orbits – and slower when it is farther away – when a satellite “falls” from high altitude to lower altitude (due to atmospheric drag), it gains speed. When it rises from low altitude to higher altitude, it loses speed. Satellites use on-board fuel to “correct” their orbital altitude.
Eventually, drag can shorten a satellite’s lifespan by making it use more fuel to maintain its orbit.
Most satellites orbiting the Earth do so at altitudes between 160 and 2,000 kilometers, according to Aerospace Security. This orbital regime is called “low Earth orbit” (LEO), due to the satellites' relative closeness to the Earth
Scientists are constantly monitoring the Sun for solar activity and develop ways to predict and mitigate the effects of solar storms.
It’s a reminder that space is challenging – getting satellites or astronauts into orbit is no easy feat.
