Mars Orbit Wobble Could Be Evidence of Dark Matter, MIT Study Reveals

A potential new method for detecting dark matter involves monitoring subtle changes in the Red Planet’s orbit, caused by passing primordial black holes.

A groundbreaking study from the Massachusetts Institute of Technology (MIT) proposes that a subtle wobble in Mars’ orbit could provide new evidence of dark matter, specifically in the form of primordial black holes. The research, led by MIT physicists, suggests that these microscopic black holes could be zooming through our solar system every decade, potentially affecting the Red Planet’s trajectory.

The study, recently published in Physical Review D, explores the idea that primordial black holes, which are believed to have formed less than a second after the Big Bang, could make up a significant portion of the universe’s dark matter. Unlike particle-based searches for dark matter that have so far yielded little success, this new approach looks for gravitational effects caused by these tiny but massive objects.

According to lead author Tung Tran, the team’s simulation showed that a black hole flyby near Mars could cause a detectable wobble in the planet’s orbit. “If a primordial black hole were to pass within a few hundred million miles of Mars, the encounter would create a wobble in its orbit by about a meter,” said Tran. Given the precision with which scientists monitor Mars’ position, even a tiny shift could be significant.

Primordial Black Holes: A Different Approach to Dark Matter

Dark matter, an invisible substance that makes up around 80% of the universe’s matter, has long puzzled scientists. Most research has focused on detecting dark matter as exotic particles that scatter or decay into observable forms. However, the MIT team is revisiting a theory first proposed in the 1970s: that dark matter could instead consist of primordial black holes. These black holes, much smaller than their astrophysical counterparts, could be as small as an atom but as heavy as large asteroids.

David Kaiser, professor of physics at MIT and co-author of the study, emphasized that Mars offers a unique opportunity to test this hypothesis. “We’re taking advantage of this highly instrumented region of space to look for a small effect,” Kaiser explained. “If we see it, that would support the idea that primordial black holes are a primary source of dark matter.”

Simulations and the Search for Evidence

The team’s simulations, based on estimates of dark matter’s density in space, suggested that a black hole as massive as an asteroid could pass through the inner solar system roughly once every 10 years. These encounters could introduce slight deviations in the orbits of planets like Mars, which is monitored with extreme precision from Earth.

While the effect on Earth and its moon was harder to predict, Mars seemed to offer a clearer picture. Instruments already in place to track the planet’s movements could detect a shift caused by a passing black hole. Still, much work remains before scientists can definitively attribute such a wobble to dark matter. The team plans to collaborate with other experts to simulate a wide range of objects moving through the solar system to differentiate between mundane space rocks and black holes.

A New Path in the Search for Dark Matter

Sarah Geller, another co-author and postdoc at the University of California at Santa Cruz, stressed the importance of further simulations and data analysis. “We are working to simulate a huge number of objects, from planets to moons and rocks, and how they’re all moving over long time scales,” Geller said. The goal is to refine the search for close encounters and distinguish between ordinary space debris and primordial black holes.

This study opens a new frontier in the ongoing search for dark matter, offering an innovative way to detect these elusive objects. As Matt Caplan, a physicist at Illinois State University, noted, “Whether or not a search finds a loud and clear signal depends on the exact path a wandering black hole takes through the solar system. Now that they’ve checked this idea with simulations, they have to do the hard part — checking the real data.”

This research was supported by the U.S. Department of Energy and the National Science Foundation.