When the universe’s clock began to tick 14 billion years ago, space was still a tight, blazing hot, frenzied packet of cosmic stuff. Stars had yet to shine, planets had yet to be born, and jittery particles of all shapes and sizes whizzed around at random.
A few minuscule, unstable, and hyper-dense pockets of flaming matter may have collapsed somewhere amid the lawlessness, in between spirals of stardust. Scientists believe that if they did, they would have dotted the early universe with clusters of black holes as small as atoms.
Don’t be fooled by these tiny spheres of doom. A black hole half the size of a golf ball would have the same mass as Earth. Even microscopic black holes with masses comparable to asteroids would have sucked in and destroyed everything in their path indefinitely.
Swarms of them would have seen planetary systems rise and fall slowly as the universe progressed, and there’s a good chance they’d have whizzed through our corner of the cosmos billions of years ago. These mini black holes would have eventually drifted apart. Experts believe that if they did exist, they would be roaming the galaxies right now.
To ensure that this novel hypothesis does not become a dead end, we would need to find unseen, miniature versions of black holes. But how? We have enough trouble finding supermassive, visible ones with high-tech equipment tailored to the search.
But, even though we can’t see it, dark matter isn’t clever enough to hide its effects. That is how scientists discovered the existence of the hidden material in the first place. According to Sarah Shandera, associate professor of physics and director of Pennsylvania State University’s Institute for Gravitation and the Cosmos, the way astrophysical bodies move within the universe proves dark matter exists.
According to Shandera, one limitation of the theory is that astronomers aren’t yet studying the type of super small, early universe fluctuations required to create microscopic, primordial black holes. Instead, they study such perturbations on larger scales, because there’s more research to support the greater size.
Caplan conceived the ambitious theory three years ago when he asked Yalinewich a simple question: Can you tell whether a crater was formed by a regular impact or by a compact object, such as a black hole, based on the shape of the crater?
He realized the difference is in how matter splashes around when something falls into it. If we threw a penny onto a table of baby powder, dust particles would rise and land around the coin’s edge. Craters work in the same way: asteroids collide with the moon, creating a hill that tapers off around the impact site, giving the resulting crater its valley-like appearance. The hill around the crater rim changes, though they still look like the round craters we’re used to seeing. It would be steeper and taller, dubbed the ejecta blanket. The black hole would also leave an exit wound, similar to a bullet, on the other side of the moon.
While these eerily small black holes could have slammed into the early Earth, our planet’s atmosphere would have shielded it from the brunt of the impact. According to Caplan, any data from a possible collision would have been erased by erosion on Earth’s surface. That means that as long as our atmosphere remains intact – unless climate change has other plans for the planet – Earth will be safe from tiny black holes. In any case, the researchers believe that by now, these baby astrophysical bodies would be so far apart that the possibility of one of them colliding with us isn’t a concern.
They claim that because these black holes have a hyper-intense gravitational impact that is incomprehensible to the human mind, they would have hit the moon with enough force to change the properties of matter around it. Nuclear weapons behave similarly. The first was notorious for transforming all of the sand near its detonation site into glass.
However, finding these altered materials would necessitate astronauts returning samples from the lunar surface or sending a probe to the moon capable of sampling rocks, similar to how Mars rovers work. NASA hasn’t sent anyone to the moon since the 1970s, but the Artemis missions are attempting to do so this decade.