This illustration shows Earth surrounded by theoretical filaments of dark matter called "hairs." Image: NASA/JPL-CaltechIf dark matter were visible, the Earth would be in need of a haircut.

A researcher from NASA’s Jet Propulsion Laboratory (JPL) published a new study in the Astrophysical Journal proposing the existence of long filaments of dark matter, or hairs, near planetary bodies.

Undetectable, dark matter comprises 27% of all matter and energy in the universe. All the planets, stars, asteroids, meteoroids and anything visible is made up of matter, which is about 5% if the universe. Scientists are certain dark matter exists, however, it has never been directly detected. According to NASA, “the leading theory is that dark matter is ‘cold,’ meaning it doesn’t move around much, and it is ‘dark’ insofar as it doesn’t produce or interact with light.”

Calculations from the 1990s showed dark matter forms fine streams that orbit galaxies. Researcher Gary Prézeau said, “A stream can be much larger than the solar system itself, and there are many different streams crisscrossing our galactic neighborhood.”

“When gravity interacts with the cold dark matter gas during galaxy formation, all particles within a stream continue traveling at the same velocity,” said Prézeau, who used computer simulations in his study

Unlike regular matter, a filament of dark matter would pass right through Earth. And Earth’s gravity would actually focus and bend the dark matter into a denser hair, according to Prézeau. These hairs are complete with proverbial “roots” and “tips.”

Dark matter passing through the planet forms the root, a concentrated area about a billion time denser than average. The root would form about 600,000 miles from Earth’s surface, and the tip would be twice as far as that.

“If we could pinpoint the location of the root of these hairs, we could potentially send a probe there and get a bonanza of data about dark matter,” said Prézeau.

“Dark matter has eluded all attempts at direct detection for over 30 years,” added Charles Lawrence, the chief physicist of JPL’s astronomy, physics and technology directorate. “The roots of dark matter hairs would be an attractive place to look, given how dense they are thought to be.”

Interestingly, changes in the planet’s density, from the inner and outer cores to the mantle and crust, would be reflected as “kinks” in the dark matter hair, Prézeau’s research found.

According to NASA, if the information were obtainable, scientists could use dark matter hairs to map out the layers of planetary bodies, including the depths of oceans.