Dark matter near Mars?

If a theory about dark matter is true, it would be possible to detect the passage of such matter near Mars.

Dark matter is an unknown type of matter that cannot be detected except by its gravitational influence. It is more abundant in the cosmos than normal matter. It does not correspond to conventional black holes or any other known type of star. No one has seen it and no one knows what it is, although there are theories about its nature.

In a new study, a team led by Tung Tran of the Massachusetts Institute of Technology (MIT) and now at Stanford University in the United States has proposed a feasible way to capture dark matter in our interplanetary neighborhood — provided that there is dark matter here, and that all or almost all of it consists of primordial microscopic black holes of a hypothetical kind, created in the very first moments of the universe’s existence as a direct consequence of the Big Bang. Such black holes would be the size of an atom and have a mass comparable to that of an asteroid — characteristics impossible to achieve by any of the natural phenomena in the universe today that create black holes.

Monitoring whether certain very subtle oscillations occur in the orbit of Mars, but which indicate the action of a force that is not one of those contemplated by common causes, could be the key to detecting the passage of dark matter of this kind through this area of ​​our solar system.

Thanks to decades of precision telemetry, since Mars has had the most spacecraft orbiting it after Earth, scientists know the distance between Earth and Mars to within about 10 centimeters. This knowledge would allow them to detect the subtle but telltale effect of a passing microscopic black hole.

Such a detection would reveal that dark matter is a collection of microscopic black holes, each about the mass of an asteroid, that were created moments after the Big Bang from the collapse of dense pockets of gas and scattered across the cosmos as the universe expanded and cooled. If they exist, primordial black holes do not reside in solar systems; they are wanderers; if unstoppable, they travel endlessly through the universe.

Artist’s impression of a dark matter clump (left) near Mars (right). (Illustration: Jorge Munnshe for NCYT by Amazings)

According to some estimates, if a primordial black hole were to pass at its typical speed within 1 meter of a person, its gravitational force would pull the person up to 6 meters away in a single second. Still, the odds of a primordial black hole passing close to a person on Earth are astronomically unlikely.

Instead, if that is the primary nature of dark matter, then statistically one such black hole should pass through our solar system at least once per decade.

With this passing rate in mind, the authors of the new paper ran digital simulations of several asteroid-mass black holes flying through the solar system, from various angles and at speeds of about 150 miles per second. (These estimates of directions and speeds come from other studies of the distribution of dark matter in our galaxy.) The authors of the new paper focused on cases where the black hole passed close enough to a star to have a noticeable effect on it. They found that, unfortunately, any effects on Earth or the Moon were too uncertain to be attributed to such a black hole. On the other hand, on Jupiter and other stars farther from the Sun than Mars, the effects would not be detectable from Earth.

Fortunately, however, the effects on Mars would be fairly unambiguous.

Researchers found that if a primordial black hole were to pass within a few hundred million kilometers of Mars, the encounter would cause a “wobble,” or slight deviation in Mars’ orbit, on a scale that current technology could detect. (Source: NCYT by Amazings)