The Sun provides nearly all Earth’s energy, but it’s also a hazard. Our nearby star occasionally emits a tremendous energy jet that knocks down technology.
Here’s the worrisome part: Earth hasn’t been hit by powerful space weather since humanity started relying on technology. As the Sun nears peak activity, some worry about potential threats.
Space weather specialists claim we’ve had a couple of low-level events recently. Interesting Engineering got down with heliophysics Gregory D. Fleishman, a specialist on the Sun’s outer layers, to learn more.
Length and clarity were edited.
What’s space weather?
Gregory D. Fleishman: It discusses interplanetary conditions that affect Earth’s infrastructure, technology, and life. Space weather has many components. The solar wind is the ground state. Uneven solar wind. It’s Sun-bound plasma. Not steady-state. This persists. Depending on plasma velocity, the solar wind can be fast or sluggish.
IE: It’s common. Rare processes include…
Fleishman: The ground state is then perturbed. This disruption is co-rotating structures or CIR. Interplanetary coronal mass ejections are ejections of plasma bubbles and magnetized plasma.
Space weather also includes energetic charged particles, which can be created by solar flares or CME shockwaves.
Finally, there’s the solar radiation itself, the electromagnetic waves. These solar flares emit radio waves, X-rays, and gamma rays.
What does this signify for Earth?
Fleishman: All of these elements have physical impacts and concerns for technology, infrastructure, and astronaut health. Strong radio bursts, especially polarized ones, can disable all GPS navigation devices on the sunny section of Earth. This is critical and dangerous since you need the GPS to work 24/7. If it’s disrupted, even for 15 minutes, it won’t work.
What if a burst impacted New York City?
Imagine living on the Moon, which has no atmosphere or magnetic field, says Fleishman. The Moon will hit such bubbles. If big enough, it’d demolish New York City. Craters dot the moon’s surface. There’s no shield.
We have a shield on Earth, right?
Fleishman: Earth has two protective shields. Atmospheric meteors burn up. The terrestrial magnetic field protects humans from charged particles from the Sun or galactic cosmic rays. The magnetic field shelters Earth from particle strikes. Charged particles revolve around magnetic field lines and can only travel to the poles or into radiation belts.
The magnetic field protects against CMEs. Magnetized bubbles. They strike Earth’s magnetic field. When this happens, intriguing physical phenomena occur, such as sandstorms, but there is no direct influence on New York City. It’s widespread and sheltered by the atmosphere and magnetic field.
1859 solar storm caused issues on Earth. What happened, and how would things be different now?
Fleishman: This is well-known. Only the telegraph was affected. Electromagnetic fields induce electric currents in cables. Electromagnetic fields and electric current are used in a lab. More EM field, more electric current. Too much electricity in the cables causes heat. Overloading the wire might damage equipment. It’s grave. A similar occurrence now would harm far more sophisticated systems. All modern technology that relies on electromagnetic fields or waves will be harmed.
Do most solar ejections miss Earth? How often do they happen?
Fleishman: Yes, it’s a matter of statistics. If we have a few ejections per day during solar maximum years and each has an opening angle of 20 or 30 degrees, then around 5 to 10% of all ejections will hit Earth. The Sun’s polar regions don’t produce most ejections. They’re about 20 degrees from the solar equator. Every tenth or twentieth ejection hits Earth or its magnetosphere.
We have a massive fleet of satellites, and many are distant from Earth and face the Sun. Even non-Earth events can hit a satellite. It’s persistent. Engineers who build satellites must consider these implications.
Sometimes, these events occur more commonly. Describe the pattern.
Fleishman: Sunspots have minimums and maximums every 11 years. It oscillates, but it’s not. Change. Cycle lengths vary. After one cycle ends, a new one begins, and solar surface activity increases. Solar flares, jets, and mass ejections will increase proportionally. Sunspots roughly correlate.
If you have one sunspot with a 10% chance of erupting, you may or may not. Hundreds of active regions with a 10% chance will create at least 10 active regions. This is how it works in 2025. Many active zones, some flare-producing, are likely. Solar activity will increase proportionately.
Why do sunspots cause ejections?
Fleishman: Sunspots are dark areas where the plasma or gas temperature is lower than around them. How come it’s cooler? Because it’s stronger than outside. It blocks plasma. This reduces heat transfer from below to above. Less heat reduces the final temperature. Dark spots indicate a strong magnetic field.
Sunspots are symptoms of a larger mechanism that produces other occurrences.
Yes. An isolated sunspot won’t produce many flares since it won’t have enough magnetic energy. Magnetic energy is free. Free magnetic fields require electric currents. These appear as sigmoidal flux tubes, curved structures, or shared motion. When negative and positive magnetic fields collide and shift, stress and tension result. This is energy-free. This requires positive and negative magnetism.
Simply put, you need two sunspots with positive and negative magnetic fields. If they’re close, you’ll see free energy structures. Once it’s knotted and intricate enough, an explosion occurs because the system lacks stability.