How do you feel when you view the aurora?
An aurora, often known as the northern or southern lights, is light emitted by upper atmospheric particles when they interact with charged magnetosphere particles.
It’s an awe-inspiring and unearthly phenomenon that folks living in high latitudes might witness on a regular basis. The northern lights are ancient spirits who stay and communicate from the sky, according to Cree and Ojibwe teachings.
According to experts, the aurora is an immensely complex concoction of ionospheric processes, a manifestation of Earth’s inherent link to the sun. To industry, it is a risk element.
The Starlink destruction event
SpaceX deployed 49 Starlink broadband satellites into low-Earth orbit (LEO) in February 2022. This was SpaceX’s 36th Starlink launch, and they expected it to go off without a hitch, just as the previous 35 had.
A coronal mass ejection – a massive burst of plasma ejected from the sun – slammed Earth on launch day. It generated a geomagnetic storm in the atmosphere between 100 and 500 kilometers altitude, the Starlink target range.
This occurrence shot a massive amount of electromagnetic radiation directly into Earth’s upper atmosphere.
The energy produced stunning auroral displays, but it also increased the density of the air. Higher air density isn’t usually a problem for LEO satellites because it’s already extremely low at normal operational altitudes (up to 400 kilometers).
Starlink, on the other hand, was initially launched at a height of 210 kilometers. That’s significantly closer to Earth, with much higher air density. Thirty-eight of the initial 49 launch satellites were lost owing to atmospheric drag from the dense atmosphere, which pulled them down to Earth.
Surprising solar cycle
The sun goes through an 11-year cycle in which its activity increases and declines on a regular basis.
We witness more sunspots on the solar surface, more radiation emitted, and more solar flares during the top of a cycle.
Geomagnetic storms like the one that destroyed Starlink are relatively common, especially when the sun is at the pinnacle of its 11-year cycle of strengthening and decreasing activity.
There were 927 storms classified as moderate or weak alone in the previous cycle, which concluded in 2019 (the 24th monitored cycle since 1755), an average of one every five or so days.
We are already four years into Solar Cycle 25, but it has already surprised us.
The 25th cycle’s maximum activity was anticipated to occur in 2025, but solar activity has already exceeded that. This means that there have been more geomagnetic storms, auroral displays (at lower latitudes than usual), and potentially more hazardous conditions for LEO satellites.
Space weather – the unseen force of nature
Why don’t geomagnetic storms cause more problems if they’re so common? The truth is that they do, but the repercussions are far less visible than satellites exploding in the atmosphere.
When space weather radiation, for example, penetrates Earth’s high atmosphere, the ionospheric composition changes in addition to the air becoming denser. To broadcast over vast distances, high-frequency, or “shortwave,” radio transmission relies on a predictable ionosphere.
Geomagnetic storms that disturb ionospheric composition, such as the one that occurred in North America on August 7, can induce radio blackouts. Minor storms can degrade radio transmissions used in military and naval systems, aviation communication, or amateur radio.
Extreme storms can generate radio outages that persist for hours and cover a whole continent. Storms of that magnitude can also generate more visible issues, such as the nine-hour power outage suffered by Hydro-Québec in 1989.
Space weather warning systems
But it’s not all doom and collapsing rockets. We can detect when a solar flare leaves the sun’s surface and anticipate when it will impact the Earth, providing warning of certain sorts of storms and opportunities to witness the aurora.
Many storms, however, have little or no prediction capability since they are dependent on how the Earth’s magnetic field interacts with the solar wind, which is more difficult to perceive.
One of our most powerful tools is nowcasting, which uses real-time data to comprehend conditions as they occur. We can measure the electromagnetic space weather energy entering the atmosphere nearly instantly using devices like ground-based radar and magnetometers on satellites.
It was only a matter of timing when SpaceX lost satellites in February 2022 during a mild geomagnetic storm. The loss of the satellites, on the other hand, is a stunning reminder of the power of the cosmos in which we live.
Daniel Billett, Postdoctoral Fellow in Space Physics, University of Saskatchewan
This article is republished from The Conversation under a Creative Commons license. Read the original article.
