Dark Dwarfs: New Star-Like Objects May Reveal Nature of Dark Matter

Astronomers predict an unseen class of star-like bodies called “dark dwarfs” near our galaxy's center. A new study suggests these objects could shine thanks to annihilating dark matter, not nuclear fusion. Dark matter makes up about a quarter of the universe and interacts via gravity. If WIMP-like dark matter particles collect in a brown dwarf, they would annihilate and heat it, causing a faint glow. Dark dwarfs would be too light to fuse hydrogen, but would keep lithium-7 in their atmospheres, offering a signature. This prediction comes from a JCAP study. The discovery of one could reveal dark matter's nature.

Predicted Dark Dwarf Properties

According to the paper, sub-stellar objects just below the hydrogen-burning threshold would be powered by dark matter. The authors find that the minimum mass for hydrogen fusion shifts above ∼0.075 M⊙ in dense dark-matter environments, so lighter brown dwarfs instead become stable dark-matter–powered stars ('dark dwarfs') via WIMP annihilation inside them. They predict such objects only appear in regions with extremely high dark-matter density, like the Galactic center (ρ_DM ≳ 10^3 GeV/cm^3), because further out the halo is too tenuous. Crucially, dark dwarfs should retain lithium-7 in mass ranges where ordinary brown dwarfs burn it away, providing a clear observational signature.

Observational Prospects and Implications

Sakstein notes that powerful telescopes like the James Webb Space Telescope might even already detect extremely cold objects like dark dwarfs near the galactic center. Alternatively, astronomers could survey brown dwarf populations for a rare sub-class with anomalous lithium content. Notably, even one confirmed dark dwarf would strongly favor heavy, self-annihilating dark matter.

Sakstein explains that finding dark dwarfs would provide “compelling evidence” for dark matter that is massive and interacts with itself – essentially WIMPs or similar particles. He notes that lighter candidates (like axions) would not produce such stars, so a dark dwarf discovery would disfavor those models. While not a proof of WIMPs, a dark dwarf detection would imply dark matter behaves like WIMPs (heavy and weakly interacting). Indeed, future surveys and JWST observations will also test these predictions.

Comments

Telegram Bot Reportedly Spotted Selling Sensitive Personal Data of Indian Users

Telegram reportedly has a bot that sells sensitive personal data of Indian users to willing buyers. As per the report, the bot operates independently and shares information such as names, addresses, father's name, and even Aadhaar, Pan Card, and Voter ID numbers. The bot reportedly lets users find the full profile data of another Indian user based on their phone number. It also charges a fee for this service, which starts as low as Rs. 99. Telegram Bot Charges Rs. 4,999 for Bulk Plans The Telegram bot was discovered by Digit. The publication did not reveal the name of the bot to avoid its misuse or spread, but mentioned that its existence was revealed to them via a tip. Bots are a staple feature of Telegram, and can be created by anyone. These bots can be set up to send automated messages, connect to databases, and even handle financial transactions. As per the report, this bot was designed to provide users with sensitive user data of users based on a mobile number. However, before...

Two Spacecraft Recreate Artificial Solar Eclipses to Observe the Sun’s Superhot Corona

Two spacecraft have achieved a rare milestone: recreating a total solar eclipse in space. The European Space Agency's (ESA) Proba-3 mission released the first images on June 16 from a successful test where one satellite blocked the sun's light, allowing the other to capture the blazing outer atmosphere—the corona. Unlike fleeting eclipses on Earth, this artificial version offers prolonged, repeated observations. “We could see the corona without any special image processing,” said Andrei Zhukov of the Royal Observatory of Belgium. “It was just visible there, like during a natural total solar eclipse.” ESA's Proba-3 Spacecraft Recreates Eclipses to Study Sun's Million-Degree Corona in Unprecedented Detail As per ESA reports, the Proba-3 spacecraft orbits Earth in an elliptical path, up to 60,000 kilometres at the far end. During alignment, they float a mere 150 metres apart, one satellite casting an accurate shadow on the other. This method allows scientists to block the ...

CSIRO Uses Quantum AI to Revolutionize Semiconductor Design

Researchers at Australia's CSIRO have achieved a world-first demonstration of quantum machine learning in semiconductor fabrication. The quantum-enhanced model outperformed conventional AI methods and could reshape how microchips are designed. The team focused on modeling a crucial—but hard to predict—property called “Ohmic contact” resistance, which measures how easily current flows where metal meets a semiconductor. They analysed 159 experimental samples from advanced gallium nitride (GaN) transistors (known for high power/high-frequency performance). By combining a quantum processing layer with a final classical regression step, the model extracted subtle patterns that traditional approaches had missed. Tackling a difficult design problem According to the study, the CSIRO researchers first encoded many fabrication variables (like gas mixtures and annealing times) per device and used principal component analysis (PCA) to shrink 37 parameters down to the five most important ones. ...

Kartavya Kant Tiwari

Search This Blog