Scientists Say Dark Matter Could Turn Failed Stars Into ‘Dark Dwarfs’

Astronomers now suggest that “failed stars” often called brown dwarfs may very well be powered by darkish matter. Dark matter makes up about 85 % of the universe’s matter however doesn’t shine; it interacts solely through gravity. Brown dwarfs type like stars however lack sufficient mass to ignite fusion. The idea suggests brown dwarfs in galaxy facilities may lure darkish matter of their interiors. When that darkish matter annihilates, it releases vitality that heats the star, turning the dwarf right into a brighter “dark dwarf.” If such objects exist, discovering them would give scientists a brand new clue to the character of darkish matter.

Dark Matter in Failed Stars

According to the brand new mannequin, dense brown dwarfs on the facilities of galaxies act like gravity wells that accumulate darkish matter. Because darkish matter interacts solely through gravity, it naturally drifts to galactic cores, the place it may be captured by star. As University of Hawai‘i physicist Jeremy Sakstein explains, as soon as inside a star darkish matter can annihilate with itself, releasing vitality that heats the dwarf. The extra darkish matter a brown dwarf collects, the extra vitality it outputs. Crucially, this impact solely works if darkish matter particles self-annihilate (as with heavy WIMPs); lighter or non-interacting candidates like axions wouldn’t create darkish dwarfs.

They suggest utilizing a chemical signature: a darkish dwarf ought to maintain on to lithium-7 that ordinary brown dwarfs burn away. The researchers say highly effective telescopes like NASA’s James Webb Space Telescope may already be delicate sufficient to identify cool, dim darkish dwarfs close to the Milky Way’s middle. Detecting even one would strongly counsel that darkish matter is fabricated from heavy, self-interacting particles (like WIMPs).

In associated work, Colgate astrophysicist Jillian Paulin coauthored research of historical “dark stars” fueled by darkish matter, whereas SLAC physicist Rebecca Leane and collaborators have proven that darkish matter seize might warmth brown dwarfs and exoplanets – a course of known as “dark kinetic heating”. Together, these concepts spotlight how even dim, uncommon stars might illuminate the character of darkish matter.