At midnight on Mars, the red planet’s magnetic field sometimes starts to pulsate in ways that have never before been observed. The cause is currently unknown.
That’s just one of the stunning preliminary findings from NASA’s very first robotic geophysicist there, the InSight lander. Since touching down in November 2018, this spacecraft has been gathering intel to help scientists better understand our neighboring planet’s innards and evolution, such as taking the temperature of its upper crust, recording the sounds of alien quakes, and measuring the strength and direction of the planet’s magnetic field.
As revealed during a handful of presentations this week at a joint meeting of the European Planetary Science Congress and the American Astronomical Society, the early data suggest the magnetic machinations of Mars are marvelously mad.
In addition to the odd magnetic pulsations, the lander’s data show that the Martian crust is far more powerfully magnetic than scientists expected. What’s more, the lander has picked up on a very peculiar electrically conductive layer, about 2.5 miles thick, deep beneath the planet’s surface. It’s far too early to say with any certainty, but there is a chance that this layer could represent a global reservoir of liquid water.
On Earth, groundwater is a hidden sea locked up in sand, soil, and rocks. If something similar is found on Mars, then “we shouldn’t be surprised,” says Jani Radebaugh, a planetary scientist at Brigham Young University who was not involved with the work. But if these results bear out, a liquid region at this scale on modern Mars has enormous implications for the potential for life, past or present. (Get the facts about previous evidence for an underground lake on Mars.)
So far, none of these data have been through peer review, and details about the initial findings and interpretations will undoubtedly be tweaked over time. Still, the revelations provide a stunning showcase for InSight, a robot that has the potential to revolutionize our comprehension of Mars and other rocky worlds across the galaxy.
“We’re getting an insight into Mars’s magnetic history in a way we’ve never had before,” says Paul Byrne, a planetary geologist at North Carolina State University who was not involved with the work.
A tale of two worlds
Earth has a major global magnetic field thanks to its rotation and churning, iron-rich, liquid outer core. We know that this field has been around for a while and that it has shifted about fairly dramatically across geological epochs, based on natural records of its strength and direction trapped in specific minerals within the crust. The history of Mars’s magnetic field is similarly archived in its crust, as scientists learned in 1997 thanks to data from the Mars Global Surveyor orbiter.
“The same zoo of magnetic minerals that exist on Earth exist on Mars,” says Robert Lillis, a planetary space physicist at the University of California, Berkeley, who wasn’t involved with the new research.
Source: National Geographic