Scientists Just Discovered Earth May Be Closer to Becoming Mars Than We Thought
What's not so commonly known is, what went wrong.
Mars once had a protective magnetic field generated by a molten, churning iron core. It's amazing that a force field of sorts can be generated around the entire planet, protecting it from deadly solar radiation. Scientists call it a geodynamo process. The outer core was made of molten iron, which conducts electricity. Heat from the inner core causes the molten iron to move around in huge convection currents. As Mars spun, the flow of liquid iron organized into spirals and -- astoundingly -- generated powerful electric currents. And those currents formed a magnetic field around the planet.
This invisible bubble of magnetism protected the Mars atmosphere from the constant blast of solar wind, a stream of high-energy particles streaming out from the Sun. But around four billion years ago, the Martian dynamo sputtered and died. The magnetic field collapsed. And without that shield, the planet's atmosphere slowly disappeared. The planet decayed into the barren, frozen, toxic world we know today.
We're very familiar with this protective magnetic bubble, because Earth has a strong one. Our molten outer core is still churning, still generating a powerful field that deflects the deadly solar wind. It's the reason our oceans remain, our air is thick enough to breathe, and our planet is not a lifeless wasteland.
We've been very confident this protection wasn't going away. Because we understood how it works, what keeps it in place.
Until now.
A new study from the Southwest Research Institute in Texas revealed we don't know as much about the solar wind as we thought -- and our magnetic field may not be so stable against it.
The study uses data from NASA's "Magnetospheric Multiscale Mission", which launched four spacecraft in orbit in 2015, specifically to observe Earth's magnetosphere. And they found something unexpected.
It was well known that things called "Pickup ions" (PUIs) exist around the sun. These are formerly neutral atoms drifting through space that are zapped into ions by the power of the sun. Once they're ionized, they get caught by the solar wind and spiral around magnetic field lines. In fact, they tend to create additional waves in the solar wind.
And that's what made this new study disturbing. The MMS spacecraft observed Pickup ions (PUIs) near Earth. Turns out, these PUIs are actively stirring up the solar wind barraging our planet. According to Dr. Michael Starkey, lead scientist on the study, "PUIs play a larger role in the heating and thermalization of the solar wind near Earth than previously thought."
It reveals a blind spot in our understanding of the toxic radiation raining down on us every minute of every day. These PUIs are stirring up turbulence and changing the heat levels of the solar wind as it hits the Earth's shield. Suddenly our confidence in how the magnetosphere holds up under stress is misplaced -- we didn't even realize this additional element was in play.
The magnetic field wouldn't have to disappear entirely for this to cause a devastating crisis. If a massive solar storm erupted, sending a coronal mass ejection hurtling toward Earth, the magnetosphere normally absorbs the shock. But if PUIs amplify turbulence in ways our models don't anticipate, the storm could opening cracks in Earth's magnetic field.
The initial problems would be scary but manageable. Satellites would be destroyed, cutting off GPS, communications, and weather forecasting. On Earth, geomagnetically induced currents would surge through power grids, frying transformers and plunging cities into darkness.
But the deeper danger is long-term. If Earth's magnetic field were ever to weaken significantly our air would become vulnerable to solar stripping. Earth's atmosphere would thin. Oceans would slowly evaporate as surface radiation levels rose. The lush, protective biosphere we depend on would slip away, leaving our planet exposed to the raw elements of space.
We keep dreaming of turning Mars into another Earth. But if we lose our magnetic field, the transformation will go the other way. Earth would become Mars.
It's highly unlikely. It would take some extraordinary event hitting us from the volatile sun to trigger the process.
Then again, based on recent solar activity, it may not be so unlikely.
Solar flares -- explosions of energy from the sun -- are ranked in size and strength in three classes: C for small, M for medium, and X class for the biggest. And within each class, numbers are added to indicate how strong they are. For example, an X2 flare is twice as strong as an X1.
In May of 2024, the sun unleashed an X8.7-class flare, one of the most powerful solar explosions our home star can produce. Its energy is equivalent to billions of nuclear bombs going off at once. The event triggered the strongest geomagnetic storm to hit Earth in 20 years.
Later that same year, the sun added an X9-class flare to the mix, making 2024 the most active year for solar weather in modern observation.
Will our magnetic bubble hold up against these growing solar explosions? Probably. But it's worth noting, looking at all the planets around us -- if Earth manages to stay 'blue', we'd be the only one.
