Tag

Stellar Evolution

All articles tagged with #stellar evolution

science2 days ago•9 min saved

Astronomers Identify First 'Phoenix Planet' Formed From Dead Star's Ashes

A team led by the University of Warwick has identified a likely second-generation planet orbiting the white dwarf HS 0209+0832. Published in Nature Astronomy, the study suggests this world formed from debris ejected by the star during its dying phase, rather than from the original protoplanetary disk. The discovery, confirmed by Hubble and TESS data, marks the first time such a planet has been found around a white dwarf, challenging the assumption that planetary formation is a one-time event tied to a star's youth.

via NDTV|

#astronomy #exoplanets #hubble-space-telescope

science-and-space4 days ago•3 min saved

Astrophotographer’s 30-Hour Capture of Dumbbell Nebula Illustrates the Sun’s Future Fate

Astrophotographer Andrew McCarthy released a 30-hour exposure of the Dumbbell Nebula (Messier 27) for his 2027 cosmic calendar, using the image to illustrate the eventual death of the Sun. The nebula, located in the constellation Vulpecula, is a planetary nebula formed by a dying star similar to our Sun. McCarthy explains that the Sun will eventually expand into a red giant, shed its outer layers, and collapse into a white dwarf, mirroring the process seen in the Dumbbell Nebula. The image was captured using Hydrogen, Oxygen, and Sulfur-tuned filters to isolate trace gases, creating a 'Hubble Palette' effect that enhances contrast while maintaining visible spectrum colors. McCarthy notes that the image serves as a reminder that the solar system has an expiration date, with the Sun’s mass eventually contributing elements to form new planets.

via PetaPixel|

#andrew-mccarthy #astrophotography #dumbbell-nebula

science4 days ago•120 min saved

First 'Second-Generation' Planet Found Orbiting a White Dwarf

Astronomers have identified the first known 'second-generation' planet orbiting a white dwarf, a world formed from the ejected material of a dying star rather than the original protoplanetary disk. The discovery, centered on the white dwarf HS 0209+0832, reveals a gas giant whose atmosphere is being stripped by intense radiation, feeding heavy elements back into the star. This finding challenges previous assumptions about planetary formation around stellar remnants and offers a new method to detect similar systems.

via Space|

#astronomy #exoplanets #nucleosynthesis

science4 days ago

Caltech Study: Random Solar Mass Ejections Will Destroy Outer Planets in 1 Billion Years

A new study led by Konstantin Batygin at Caltech argues that the outer solar system will collapse within one billion years after the Sun becomes a white dwarf, a timeline a billion times shorter than previous estimates. The research suggests that random, violent mass ejections from the dying Sun, rather than smooth mass loss, will destabilize the orbits of Jupiter, Saturn, Uranus, and Neptune. While earlier models predicted stability for trillions of years, this new analysis indicates that stochastic 'kicks' from the Sun will trigger violent scattering, potentially ending the solar system's existence far sooner than anticipated.

via futurism.com|

#astronomy #caltech #orbital-mechanics

astronomy4 days ago•45 min saved

White Dwarf HS 0209+0832 Feeds on Planet Formed from Stellar Ashes

Astronomers have identified a white dwarf, HS 0209+0832, that is accreting material from a 'second-generation' planet. This planet likely formed from the ejected envelope of the star's progenitor after it died, rather than from the original protoplanetary disk. The discovery, published in Nature, marks the first evidence of such post-stellar planetary formation around a white dwarf.

via Nature|

#astronomical-spectroscopy #astronomy #exoplanets

science5 days ago•216 min saved

White Dwarf Feeds on Planet Born from Stellar Ashes

Astronomers have identified a white dwarf star, HS 0209+0832, that is accreting material from a 'second-generation' planet. This planet likely formed from the ejected envelope of the star’s progenitor after it died, rather than from the original protoplanetary disk. The discovery, published in Nature, marks the first evidence of such post-stellar planetary formation around a white dwarf.

via CNN|

#astronomy #exoplanets #nucleosynthesis

science7 days ago•4 min saved

Solar System Collapse Timeline Shortened to One Billion Years by Random Solar Mass Ejections

New simulations suggest the outer solar system will disassemble within one billion years after the Sun becomes a white dwarf, a timeline a billion times shorter than previous estimates. The instability is driven by random, directional mass ejections from the dying Sun, which destabilize planetary orbits far sooner than smooth mass loss models predicted.

via 404 Media|

#astrophysics #orbital-mechanics #science

science7 days ago•120 min saved

MEGATRON Simulation Links First Stars to Milky Way's Chemical Fossils

A new high-resolution simulation called MEGATRON bridges the gap between early universe observations and local stellar chemistry. Led by researchers at the University of Bath, Chicago, and Paris, the project models the formation of the first stars and galaxies from 2023 to 2030. By tracking gas, radiation, and chemical evolution simultaneously, MEGATRON explains how Population III stars enriched the cosmos with heavy elements. The simulation successfully reproduces the 'iron plateau' in dwarf galaxies, suggesting that single massive stellar explosions seeded these systems with iron. This work provides a physical link between James Webb Space Telescope data of distant galaxies and the chemical fingerprints preserved in ancient Milky Way stars.

via Space|

#astrophysics #cosmology #galaxy-formation

science9 days ago•1 min saved

Stochastic Solar Mass Loss May End the Outer Solar System in 1 Billion Years

New simulations by Konstantin Batygin and colleagues at the California Institute of Technology suggest the outer solar system may disassemble within one billion years after the Sun becomes a white dwarf, a timeframe a billion times shorter than previous estimates. The study accounts for random, directional mass ejections during the Sun’s red giant phase, which create velocity kicks that destabilize planetary orbits. While smooth mass loss models predicted stability for over 10^18 years, stochastic ejections with masses around 10^-4 solar masses could trigger instability before the white dwarf stage even completes, with 90% of simulations showing breakdown within three billion years.

via AAS Nova|

#astronomy #orbital-dynamics #science

science28 days ago•3 min saved

Ancient Planetary Ingestion May Explain the Sun's Mysterious Lithium

Modeling suggests the young Sun could have swallowed a super-Earth (5–10 Earth masses), leaving chemical and structural fingerprints such as a deeper convection zone and unusually low surface lithium; the scenario is not proven and would need independent confirmation.

via WTHR|

#lithium #planetary-ingestion #science

science2 months ago•14 min saved

Rare double-supernova binary reveals history of two massive stars

Scientists report evidence that two massive stars in a binary system both exploded as supernovas, creating the Jellyfish Nebula (IC 443) and a nearby nebula (G189.6+3.3). Based on more than a decade of NASA’s Fermi observations, the progenitors were roughly 15–25 and at least 20 solar masses; their explosions occurred tens of thousands of years apart, and the remnants are likely neutron stars. This rare system provides direct clues to how massive binaries evolve and end their lives.

via KSL.com|

#binary-star #ic-443 #jellyfish-nebula

science3 months ago•3 min saved

Some Black Holes May Be Born From Earlier Black Hole Mergers

A new analysis of 155 binary black-hole mergers detected by LIGO/Virgo/KAGRA finds about 14% could be second-generation black holes formed from prior mergers, suggesting hierarchical mergers occur in dense stellar environments and can create unusually massive BHs in the 40+ solar-mass range, challenging simple stellar-collapse narratives and raising questions about their true origins.

via Gizmodo|

#black-holes #gravitational-waves #hierarchical-mergers

space3 months ago•104 min saved

Earth Could Outsmart the Sun's Final Farewell, New Study Finds

New models of how aging stars interact with nearby planets suggest Earth could avoid being engulfed as the Sun swells into a red giant. The study finds that weaker tidal forces and mass loss from the Sun could allow Earth (and Mars) to migrate outward, while Mercury and Venus are still doomed to be swallowed. The outcome depends on uncertain mass-loss rates during the Sun’s final stages; with current data, Earth’s survival is possible but not guaranteed, and more observations of sun-like giants are needed, the team reports in Astronomy & Astrophysics.

via Space|

#astronomy #earth #planetary-systems

space3 months ago•112 min saved

Earth May Outlive the Sun: A Delicate Cosmic Tug-of-War Could Spare Our World

New stellar-evolution models and observations of a nearby dying star suggest Earth could survive the Sun’s giant phases if solar mass loss dominates over tidal forces, allowing Earth to move outward rather than be engulfed. Mercury and Venus are still expected to meet a fiery end, but the outcome hinges on how much mass the Sun will lose—an uncertainty researchers are currently trying to resolve, with future missions like PLATO expected to help. A Letter to the Editor in Astronomy & Astrophysics outlines these calculations and the remaining questions about Earth’s ultimate fate.

via Live Science|

#earth #planetary-fate #space

science3 months ago•3 min saved

Earth Could Escape the Sun’s Death by a Cosmic Tug-of-War, Study Finds

New modelling suggests Earth might avoid engulfment by the Sun if solar mass loss dominates tidal dissipation; the planet could drift outward as the Sun expands into a red giant and finally a white dwarf, while Mercury and Venus are still likely to be swallowed and life on Earth would end due to rising luminosity.

via geekspin|

#astronomy #earth #science