STELLAR CHEMISTRY
Do "completely dark" dark matter halos exist?
illustration only
Do "completely dark" dark matter halos exist?
by Michelle Franklin for UCSD News
San Diego CA (SPX) Apr 14, 2025
Every galaxy is thought to form at the center of a dark matter halo - a region of gravitationally bound matter that extends far beyond the visible boundaries of a galaxy. Stars are formed when gravity within dark matter halos draws in gas, but astrophysicists don't yet know whether star-free dark matter halos exist.

Now Ethan Nadler, a computational astrophysicist at UC San Diego, has calculated the mass below which halos fail to form stars. This work was done using analytic predictions from galaxy formation theory and cosmological simulations.

"Historically, our understanding of dark matter has been linked to its behavior in galaxies. A detection of completely dark halos would open up a new window to study the universe," stated Nadler.

Previously, this threshold for star formation was thought to be between 100 million to 1 billion solar masses due to cooling of atomic hydrogen gas. Nadler's research shows that star formation can occur in halos down to 10 million solar masses through molecular hydrogen cooling.

With the Rubin Observatory coming online later this year and JWST already making unprecedented observations of our universe, there will soon be new data to test these predictions and reveal whether completely dark halos exist. This may have far-reaching consequences for cosmology and the nature of dark matter.

Research Report:The Impact of Molecular Hydrogen Cooling on the Galaxy Formation Threshold

Related Links
UCSD
Stellar Chemistry, The Universe And All Within It

Tweet

STELLAR CHEMISTRY
FSU researchers part of TESSERACT's hunt for dark matter
Tallahassee, FL (SPX) Mar 25, 2025
For decades, people have been trying to directly detect dark matter: the missing mass in our universe. Now, research from the FAMU-FSU College of Engineering is making possible a new, super-sensitive detector - and even though it's still in the research and development phase, it's already been able to search for kinds of dark matter that other detectors can't find. Historically, most dark matter searches have hunted for two kinds of dark matter: ultra-light axions and heavier WIMPs (weakly interac ... read more

STELLAR CHEMISTRY
Puerto Rico's power plants go offline, leading to widespread island blackout

Using liquid air for grid-scale energy storage

AI surge to double data centre electricity demand by 2030: IEA

Iraq signs deal with US firm to produce 24,000 MW of electricity

STELLAR CHEMISTRY
Chinese EV battery giant CATL posts 33% surge in Q1 profit

A new path to self-powered infrastructure with thermoelectric cement

Sophisticated fire use revealed in Ice Age hearths from Ukraine

Smart home platform lowers energy costs and boosts grid resilience

STELLAR CHEMISTRY
US halts Equinor's huge New York offshore wind project

Chinese energy giant Goldwind posts annual growth as overseas drive deepens

Clean energy giant Goldwind leads China's global sector push

Engineers' new design of offshore energy system clears key hurdle

STELLAR CHEMISTRY
Government urged to address disparity in access to green tech

Vietnam ups wind, solar targets as energy demand soars

Going green with fluoride-enhanced perovskite solar cells

Launch of AI-powered solar diagnostics platform boosts PV asset performance

STELLAR CHEMISTRY
Using AI to monitor inaccessible locations of nuclear energy systems

Czech nuclear plants to get uranium from Kazakhstan

GE Hitachi moves forward with UK SMR bid

Nuclear fuel reaches new enrichment standard

STELLAR CHEMISTRY
Turning wood waste into ultra strong material

Tunisian startup turns olive waste into clean energy

Airlines cast doubt on EU sustainable fuel targets

Eco friendly low-cost energy storage system from pine biomass

STELLAR CHEMISTRY
World-first flight test reveals how hydrogen engines form contrails

Study finds big gap in Australia's methane emissions

U.S. airstrikes targeting western Yemen oil port kill dozens

US sanctions second Chinese refinery in Iran pressure campaign

STELLAR CHEMISTRY
Trump wants to halt climate research by key agency: reports

Germany sees 'worrying' record dry spell in early 2025

Early holiday, more fans: Philippines schools adapt to climate change

Indigenous leaders want same clout as world leaders at UN climate talks