Fluffy Molecular Clouds Formed Stars in the Early Universe

This image from the research shows the overall view of the SMC and the positions of the target YSOs. Image Credit: Tokuda et al. 2025.

Stars form in Giant Molecular Clouds (GMCs), vast clouds of mostly hydrogen that can span tens of light years. These stellar nurseries can form thousands of stars. Astronomers know this because they observe these regions in the Milky Way and the Magellanic Clouds and watch as stars take shape. But the Universe is more than … Read more

What is dark energy? Exploding white dwarf stars may help us crack the case

a small white-and-blue mottled orb next to a fiery red-and-orange orb, against a background of stars

There are a lot of ways for dead stars to blow their tops. Astronomers discovered this explosive diversity when they assessed 3,628 exploding white dwarfs during a next-generation sky survey conducted using the Zwicky Transient Facility (ZTF) between March 2018 and December 2020. That means that this dataset of nearby supernovas is several times larger … Read more

Black holes snacking on small stars create particle accelerators that bombard Earth with cosmic rays

a bright orb next to a cloud of brown dust

Using 16 years of data from NASA’s gamma-ray detecting Fermi spacecraft, astronomers have discovered that “microquasars,” systems in which a black hole is slowly devouring a star, may be small, but they pack one heck of a punch. Despite their diminutive nature, this research suggests even microquasars snacking on small stars can have an impressive … Read more

The stars Shaula and Lesath herald the coming spring

Star chart showing stars Shaula and Lesath in the Tail of constellation Scorpius.

If you’re in the Northern Hemisphere, Shaula and Lesath will come over your southeastern horizon before dawn sometime this month. They’re a hopeful sign that spring is coming. How do you recognize the coming of spring? Maybe you spot a first returning robin. Or tune into news about a groundhog looking for its shadow. For … Read more

This Ancient Galaxy Cluster is Still Forming Stars When it Should be ‘Red and Dead’

This older image of the Phoenix Cluster (SPT-CLJ2344-4243) combines Chandra and Hubble's X-ray, ultraviolet, and optical wavelengths. In this new research, the team of scientists used the JWST's infrared capabilities to try to understand Phoenix better. Image Credit: By X-ray: NASA/CXC/MIT/M.McDonald et al; Optical: NASA/STScI - https://chandra.harvard.edu/photo/2015/phoenix/ (image link), Public Domain, https://commons.wikimedia.org/w/index.php?curid=45952066

The Phoenix Cluster is one of the most massive galaxy clusters known. Astronomers have identified 42 member galaxies so far, yet there could be as many as 1,000 in the cluster. Because of its size and its age, it should be finished with the vigorous star formation characteristic of young galaxies. But it’s not. Star … Read more

James Webb Space Telescope learns how a cosmic phoenix cools off to birth stars

A purple blob (the same image as header) that shows were the cooling gas is located, as seen by the JWST, and where the jet inflated bubbles are inflated, as seen by other telescopes. Both are in the middle of the purple blob, but the bubbles region is slightly lower.

How do you cool down a phoenix? I don’t mean the mythological birds of flame and rebirth, but rather a cosmic namesake with a fittingly fiery nature. Using the James Webb Space Telescope (JWST), astronomers may finally have the answer. They used the powerful instrument to investigate the extreme cooling of gas in the Phoenix … Read more

Some planet-forming stars never ‘grow up’ and lose their ‘Peter Pan’ disks

a bright white orb surrounded by dusty brown clouds

Planet formation around low-mass stars may be suffering from Peter Pan syndrome. While previous observations and models have suggested that a disk of planetary building blocks should be ‘fully grown’ – having burned through its world-making material – in about 10 million years, a new kid on the block is proving them wrong, weighing in … Read more

To Probe the Interior of Neutron Stars, We Must Study the Gravitational Waves from their Collisions

When massive stars reach the end of their life cycle, they undergo gravitational collapse and shed their outer layers in a massive explosion (a supernova). Whereas particularly massive stars will leave a black hole in their wake, others leave behind a stellar remnant known as a neutron star (or white dwarf). These objects concentrate a … Read more

Gravitational waves could turn colliding neutron stars into ‘cosmic tuning forks’

The kilonova associated with GW170817 (inset) as observed by NASA's Hubble Space Telescope (visible light) and Chandra X-ray Observatory (blue) over nine days in August 2017.

Scientists have discovered a new way to probe the interiors of neutron stars by using gravitational waves to turn them into “cosmic tuning forks.” The reverberations of such ripples in spacetime could reveal the interiors of these extreme stellar remains. Born when massive stars die, neutron stars have up to two times the mass of … Read more

Temperamental Stars are Messing With Our Exoplanet Efforts

This extraordinarily detailed image of the Sun's surface comes from the Solar Orbiter during a recent close encounter. Swirling magnetic fields help create cooler and hotter regions on the surface. Image Credit: ESA - European Space Agency

We have the transit method to thank for the large majority of the exoplanets we’ve discovered. When an exoplanet transits its star, the dip in starlight tells astronomers that a planet is present. Analyzing the light can tell them about the planet’s size and atmospheric properties. However, a star’s surface isn’t always uniformly heated. There … Read more