Stars and Stellar Evolution
88 reportsEvidence from main sequence is checked against stellar mass and white dwarf. The discussion considers how stars form and how stellar ages are estimated, comparing competing models without treating agreement as proof of mechanism.
Hubble Data Point to a Possible Planet Born After Its Star Died
Reanalyzed NASA Hubble spectroscopy and archival FUSE ultraviolet data reveal extreme niobium enrichment around the white dwarf HS 0209+0832, while TESS detected a 4.4-day brightness cycle consistent with-but not proving-the presence of a close-orbiting gas-giant candidate.
Algol's Blinking Eye Reveals an Eclipsing Star System
Algol appears to blink because two stars regularly eclipse each other. NASA's TESS data records the change while Perseus and the Witch Head Nebula add darker targets to October's night sky.
Chandra Finds 84 Hypersoft X-ray Sources Across Six Nearby Galaxies
NASA's Chandra X-ray Observatory has identified 84 hypersoft X-ray sources in six nearby galaxies. Their concentration of very low-energy X-rays may offer clues to Type Ia supernova progenitors and the ultraviolet radiation environment between galaxies.
XRISM Tracks Stellar Wind Falling Onto a Pulsar
XRISM has traced iron-rich plasma moving toward the pulsar GX 301-2 at about 540,000 kph, providing spectroscopic evidence that a neutron star captures its giant companion's stellar wind and powers recurring X-ray flares.
Youngest exoplanet yet found emerges from archival telescope data
Astronomers have identified Elias 2-24 b, the youngest known exoplanet, using direct imaging techniques and archival data from the Keck Observatory. The planet is less than a million years old and still sits within its birth disk.
Solar Storm Forces Historians to Revise Timeline of Early Technology Disruption
A new review of historical records has corrected the date of a well-known 19th-century train delay caused by a solar storm, offering a clearer picture of how early electrical systems responded to space weather.
Vampire white dwarfs can collapse into neutron stars under precise conditions
Researchers have modeled how certain white dwarfs feeding on companion stars can collapse into neutron stars if their mass and accretion rate fall within a narrow range, revealing a rare but physically distinct pathway for stellar evolution.
Hubble captures a superbubble shaping star formation in the Large Magellanic Cloud
A new Hubble Space Telescope image reveals a vast cavity in nebula LHA 120-N44, showing how massive stars reshape their surroundings and spark new star birth in a neighboring galaxy.
September sky offers rare view of five planets and the Harvest Moon
Astronomers in the Northern Hemisphere can observe all five naked-eye planets and the Harvest Moon this September as earlier sunsets and mild weather create optimal conditions for stargazing
ALMA reveals chaotic birth of massive binary stars in real time
Astronomers using ALMA have reconstructed the formation of a massive binary star system just 5,300 light-years away, finding evidence that the two stars joined forces only decades ago rather than forming together
Zodiacal Light to Illuminate September Skies Before Sunrise
A faint pyramid of zodiacal light will become visible in the eastern sky before dawn this September, offering a rare opportunity for observers to witness sunlight scattered by interplanetary dust using only the naked eye under dark conditions
Webb Telescope Reveals Rare O-Type Star Cluster in Carina Nebula
A new James Webb Space Telescope image exposes a dense cluster of newborn stars, including a rare O-type giant, inside the Treasure Chest globule in the Carina Nebula, offering a detailed look at early stellar evolution in one of the Milky Way's most active star-forming regions
Venus Reveals Its Crescent Phase as It Approaches Inferior Conjunction
Venus is now visible as a striking crescent through small telescopes as it draws closer to Earth and prepares to pass between our planet and the Sun, offering a rare chance to observe its changing phases and orbital motion
Meteorite dust reveals magnetic forces shaped the infant solar system
Analysis of ancient meteorite grains has uncovered evidence that strong magnetic fields influenced the earliest stages of the solar system's formation, challenging the long-held view that gravity alone sculpted the protoplanetary disk
Hubble Reveals Giant Superbubble Structure in Large Magellanic Cloud
A new Hubble Space Telescope image captures the nebula N44 in the Large Magellanic Cloud, highlighting a vast superbubble at its center and offering fresh insight into the impact of massive stars on their galactic environment
Supernova Experiments Reveal New Clues to Element Formation in Stars
Two new studies use nuclear experiments and astrophysical modeling to clarify how supernovae forge and distribute elements like titanium and nickel, offering the most precise look yet at the processes that shape the chemical makeup of the universe
Comet McNaught Surges in Brightness After Solar Outbursts
Comet 220P/McNaught unexpectedly brightened by a factor of 20,000 during two recent outbursts near its closest approach to the Sun, offering a rare opportunity for telescopic observation before it fades from view
Fermi Explorer Mission Targets 2029 Launch Toward Alpha Centauri
A nonprofit group aims to send a low-cost probe to Alpha Centauri by 2029, marking the first directed interstellar mission. The journey would last 80,000 years, raising new questions about the feasibility and purpose of such long-term exploration.
Stellar Spin Explains Dimming Flares from Black Hole Encounters
Astronomers have modeled why repeated flares from stars grazing supermassive black holes fade over time, revealing that a star's rotation and binary history play a key role in the observed dimming
Nancy Grace Roman Space Telescope Prepares for Launch and Legacy
NASA's Nancy Grace Roman Space Telescope, named for the agency's first chief astronomer, is nearing launch. The mission aims to investigate dark matter, dark energy, and exoplanets with advanced infrared instruments
Nancy Grace Roman's Legacy: The Astronomer Who Shaped NASA's Vision
As NASA prepares to launch the Nancy Grace Roman Space Telescope, the story of its namesake-pioneering astronomer and the agency's first chief of astronomy-offers insight into the evolution of space science and the people who shaped it
Webb Telescope Reveals Planet Formation Depends on Rapid Disk Evolution
Astronomers using the James Webb Space Telescope have tracked how gas and dust escape from disks around 72 young sun-like stars, showing that planet formation must compete with the rapid dispersal of raw material
ALMA Reveals Persistent Hotspots on Betelgeuse's Turbulent Surface
Astronomers using the Atacama Large Millimeter/submillimeter Array have mapped Betelgeuse's surface in unprecedented detail, revealing long-lived hotspots and complex plasma flows that challenge current models of red supergiant stars
Earth-Facing Sunspot Fires M6.9 Flare and CME Toward Earth
A highly active sunspot has produced an M6.9-class solar flare and launched a coronal mass ejection toward Earth, raising the possibility of geomagnetic disturbances and enhanced auroral activity later this week
Milky Way's Oldest Known Merger Leaves Lasting Mark at Galactic Center
Astronomers have identified evidence of the Milky Way's earliest known galactic merger, using Hubble Space Telescope data to trace ancient globular clusters and reveal a collision that shaped the galaxy's core nearly 12 billion years ago
Seventeen Spacecraft Reveal Asymmetric Structure in Solar Ejection
A coronal mass ejection observed in December 2024 was tracked by 17 spacecraft across the solar system, revealing an unexpected double-lobed structure with significant speed differences between its components
Dark Energy Camera Reveals Ancient Stars and Stellar Birth in Corona Australis
A new image from the Dark Energy Camera on the Blanco 4-meter Telescope captures the Corona Australis Molecular Cloud, highlighting both newborn stars and one of the oldest star clusters in the Milky Way
Webb Telescope Reveals Early Galaxies Are Richer in Small Stars
Astronomers using the James Webb Space Telescope have detected a higher proportion of faint, low-mass stars in ancient galaxies, suggesting these early systems are more massive than previously estimated
Webb Telescope Spots Candidate Black Hole Star in Early Universe
Astronomers using the James Webb Space Telescope have identified a luminous, solar-system-sized object from 660 million years after the Big Bang, offering the strongest evidence yet for a hypothesized 'black hole star' class.
Fastest Known Star Orbits Milky Way's Black Hole in Under 9 Years
Astronomers using the Very Large Telescope Interferometer have identified S301, a star orbiting Sagittarius A* at record speed, offering a new opportunity to test general relativity near the Milky Way's supermassive black hole
Hubble Data Reveals Ancient Milky Way Merger with Dwarf Galaxy
Astronomers have identified evidence that the Milky Way merged with a dwarf galaxy called LKH about 12 billion years ago, using globular cluster data from the Hubble Space Telescope and extending the timeline of our galaxy's early evolution
Five Essential Night Sky Targets for Binocular Astronomy
Astronomers highlight five celestial objects and regions that reveal striking detail through binoculars, from the Moon's shifting shadows to the Andromeda Galaxy's faint glow, offering accessible entry points for skywatchers of all experience levels
Discovery of GJ 523b Challenges Theories of Rocky Planet Formation
Astronomers have identified GJ 523b, a rocky exoplanet over 23 times Earth's mass, using TESS and ground-based spectroscopy, raising new questions about how such dense worlds form and retain-or lose-their atmospheres
Helix Nebula Reveals How Dead Stars Return Material to the Galaxy
Astronomers using the MOTHRA instrument have observed the Helix Nebula dispersing its outer layers into the interstellar medium, providing direct evidence of stellar material recycling that will enrich future generations of stars
Deneb and Cygnus: Tracing Stellar Remnants and a Nearby Black Hole
Astronomers use optical and X-ray observations to study Deneb, the Cygnus Loop supernova remnant, and the black hole Cygnus X-1, revealing the complex structure of the Cygnus constellation and its hidden extremes
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