How dark matter in exoplanets could create new black holes

• Dark matter is widespread throughout the cosmos, and makes up most of the matter in the universe. Could exoplanets help us understand it better?
• Dark matter might also accumulate inside giant exoplanets, researchers at the University of California, Riverside, say.
• Incredibly, if such a planet contains enough dense dark matter particles, they might cause a black hole to form inside it. That black hole could eventually consume the entire planet and turn it completely into a black hole.

Using dark matter to study exoplanets

The mysterious substance known as dark matter makes up most of the mass in the universe. But there is a lot we don’t know about it. Researchers at the University of California, Riverside, have suggested using exoplanets – planets orbiting distant stars – to study and better understand dark matter. They said on August 21, 2025, that dark matter particles could accumulate inside giant Jupiter-like exoplanets. Dense dark matter particles could eventually collapse to form a black hole inside a planet. The black hole could then ultimately consume the entire planet, fully transforming the world into a black hole.

Dark matter is a mysterious “substance” that scientists still know little about. We might tend to think of dark matter as something “floating around in space.” But it actually composes most of the matter and mass in the universe. This can include galaxies, gas clouds, stars and planets. Scientists say that 85% of the matter in the universe is dark matter, and just 15% is ordinary matter.

That’s distinct from the universe overall, which also includes dark energy. In that sense, 68% of the whole universe is dark energy, 27% is dark matter and 5% is ordinary matter. Dark energy is the name given to the mysterious force that’s causing the rate of expansion of our universe to accelerate over time, rather than to slow down.

The researchers published their peer-reviewed findings in the journal Physical Review D on August 20, 2025.

Dark matter in exoplanets

The new study suggests that dark matter particles could accumulate inside giant planets like Jupiter. If those particles are heavy enough, they could collapse on themselves to form a tiny black hole inside the planet. As lead author Mehrdad Phoroutan-Mehr at the University of California, Riverside, said:

If the dark matter particles are heavy enough and don’t annihilate, they may eventually collapse into a tiny black hole.

In fact, that black hole could grow until it swallowed up the whole planet. Phoroutan-Mehr said:

This black hole could then grow and consume the entire planet, turning it into a black hole with the same mass as the original planet. This outcome is only possible under the superheavy non-annihilating dark matter model.

Superheavy dark matter particles captured by exoplanets

So what happens inside the planets, according to the study? The researchers say that the planets capture superheavy (massive) dark matter particles with their gravity. Since the particles are so massive, they don’t destroy each other when they interact.

Rather, the particles lose their energy and drift downward toward the cores of the planets. That is where they accumulate. When enough particles accumulate together, they collapse together to form a black hole. There might potentially be even multiple black holes during the lifetime of the planet. Phoroutan-Mehr said:

In gaseous exoplanets of various sizes, temperatures and densities, black holes could form on observable timescales, potentially even generating multiple black holes in a single exoplanet’s lifetime. These results show how exoplanet surveys could be used to hunt for superheavy dark matter particles, especially in regions hypothesized to be rich in dark matter like our Milky Way’s galactic center.

If I were suffering from a plague of dark matter, I’d want to turn into a black hole, too. I mean, wouldn’t everyone? ???? physicsworld.com/a/exoplanets…

— Margaret Harris (@drmlharris.bsky.social) 2025-08-21T15:13:45.660Z

3 types of black holes

The black holes that scientists have found so far have masses at least that of the sun, or much greater. Right now, we know of three types of black holes. The first is the stellar-mass black hole. These are the remnants of huge stars – more than around five times the mass of our sun – that exploded in supernovas. Stellar-mass black holes have masses ranging from a minimum of about five times the mass of our sun up to about 60 times the sun’s mass. They have diameters between 10 to 30 miles (16 to 48 km).

Supermassive black holes can have masses of billions of suns. These are the types of black holes found in the centers of galaxies.

Intermediate black holes are ones with masses in between stellar and supermassive. Astronomers discovered the first one in 2021. It has a mass of about 55,000 suns.

Black holes with the mass of planets?

So, could miniature – or planetary-mass – black holes exist as well? We don’t know yet. But if so, it would support the results of the new study. As Phoroutan-Mehr noted:

Discovering a black hole with the mass of a planet would be a major breakthrough. It would support the thesis of our paper and offer an alternative to the commonly accepted theory that planet-sized black holes could only form in the early universe.

If astronomers were to discover a population of planet-sized black holes, it could offer strong evidence in favor of the superheavy non-annihilating dark matter model. As we continue to collect more data and examine individual planets in more detail, exoplanets may offer crucial insights into the nature of dark matter.

Dark matter collisions on Jupiter

Last year, scientists reported possible evidence for collisions of dark matter particles in Jupiter’s atmosphere. They might explain an unusual glow seen around midnight on Jupiter’s night side.

If so, the fact that Jupiter hasn’t (yet?) collapsed into a back hole might help scientists refine their dark matter models, including the superheavy dark matter particles model.

Scientists also said last year that tiny primordial black holes – formed just after the Big Bang – could be “hiding in plain sight.” They might have left traces behind in planetoids (including minor planets, dwarf planets and asteroids) or even right here on Earth. In fact, they could even be microscopic in size.

Bottom line: A new study suggests that particles of dark matter in exoplanets could form tiny black holes, which would eventually turn entire planets into black holes.

Source: Probing superheavy dark matter with exoplanets

Via University of California, Riverside

Read more: More evidence for black holes as the source of dark energy

Read more: Are primordial black holes hiding in plain sight?