Tag

Red Dwarfs

All articles tagged with #red dwarfs

space10 days ago•6 min saved

Red Dwarfs: The Galaxy's Quiet, Long-Lived Stars

Red dwarfs are the longest‑lived stars—potentially around 10 trillion years—thanks to slow hydrogen fusion and a convective interior that reuses fuel; they make up about three‑quarters of stars, including nearby Proxima Centauri, which hosts Earthlike Proxima b. While such systems could harbor habitable worlds, tidal locking and stellar flares complicate life, though a distant greenhouse effect could help; in any case, red dwarfs will dominate the galaxy’s stellar population long after larger stars fade.

via Defector|

#alpha-centauri #exoplanets #habitable-zone

space1 month ago•13 min saved

Ultraviolet Spotlight Reveals Four Hidden White Dwarfs Within 65 Light-Years

Astronomers using the Hubble Space Telescope’s ultraviolet observations have directly confirmed four white dwarfs hiding in the glare of nearby red-dwarf companions, all within about 65 light‑years. One, G 203-47, is the ninth-closest white dwarf to the Sun. The detections show how UV imaging can reveal faint remnants that optical surveys miss, though three of the four temperatures are only estimates due to noisier data. The census of local white dwarfs within 20 parsecs rises by roughly 16% to 153, suggesting more hidden white-dwarf–red-dwarf pairs may exist and could be uncovered with Gaia data in the future.

via Space Daily|

#hubble-space-telescope #nearby-stars #red-dwarfs

science1 month ago•4 min saved

Four Hidden White Dwarfs Detected in Nearby Binary Star Systems

Astronomers using ultraviolet data from the Hubble Space Telescope confirmed four nearby red-dwarf binaries host concealed white dwarfs, each within 65 light-years. One system, G 203-47, harbors the ninth-closest white dwarf and shows unusual, unsynchronized rotation, hinting at varied evolutionary histories for such binaries. The findings revise the local white-dwarf census and suggest more hidden companions may lurk among nearby red dwarfs.

via ScienceDaily|

#binary-star-systems #hubble-space-telescope #red-dwarfs

space2 months ago•4 min saved

Nearby Super-Earth Could Harbor Life in Red Dwarf's Habitable Zone

A refined analysis places GJ 3378b at about 2.3 Earth masses with a 21‑day orbit, situating it in the habitable zone of a nearby red-dwarf star about 25 light‑years away. Detected with infrared radial velocities using the Habitable-zone Planet Finder on the Hobby‑Eberly Telescope, the discovery highlights red dwarfs as fertile ground for rocky, potentially life-bearing worlds, though stellar activity and a possibly thin atmosphere complicate habitability. Upcoming observatories like GMT, ELT, and the Habitable Worlds Observatory could enable direct observations and biosignature searches to assess its true habitability.

via Universe Today|

#exoplanets #gj-3378b #habitable-zone

astronomy2 months ago•7 min saved

Cosmic Cannibals: Red Dwarfs Reveal Planet-Devouring Signatures

Astronomers using Gaia-ESO data found six red-dwarf stars with unexpectedly high lithium in their atmospheres, a chemical that should be destroyed deep inside these stars. Because lithium should vanish quickly, its recent appearance signals the accretion of rocky planetary material, a phenomenon dubbed necroplanetology. The six stars (out of 318 examined in clusters) suggest roughly 3–10 Earth masses of planetary matter may have been swallowed, implying planet-devouring could occur in a notable fraction of red dwarfs depending on how long lithium lasts in their atmospheres. This finding offers a new way to study planet formation and early-system evolution.

via ScienceAlert|

#astronomy #gaia-eso-survey #lithium

science1 year ago•3 min saved

Stellar Flares Rapidly Alter Planetary Atmospheres and Climate

Stellar flares from active stars like red dwarfs can rapidly alter planetary atmospheres, stripping ozone and affecting habitability, but may also contribute to prebiotic chemistry, with effects observable within days to years, including on Earth.

via The Daily Galaxy|

#atmosphere #exoplanets #habitability

space-science2 years ago•7 min saved

"Potential for Earth Life on Red Dwarf Planets"

New research examines the potential habitability of exoplanets orbiting red dwarf stars by testing the survivability of Aspergillus niger spores, which produce melanin, when exposed to simulated red dwarf radiation. The study suggests that these spores could survive the intense radiation environments on red dwarf exoplanets if shielded by a few millimeters of soil or water, highlighting the potential role of melanin in the survival of organisms in harsh conditions. This research sheds light on the possibility of life on exoplanets orbiting red dwarfs and provides insights into how melanin may have played a role in the origin and evolution of life on Earth and potentially on other worlds.

via Universe Today|

#astrobiology #exoplanets #habitability

space3 years ago•3 min saved

Reconsidering the Possibility of Life Around TRAPPIST-1

New research challenges the theory that planets like TRAPPIST-1 e were once too hot to support life, as previously believed. The study suggests that these planets may not have lost their atmospheres and water, making them potentially habitable. The findings have implications for the search for life around red dwarf stars, which make up the majority of the galaxy's sources of light. The TRAPPIST-1 system, with its seven rocky planets, is at the center of this debate. Further investigation is needed to confirm these findings and determine the potential for life in these systems.

via IFLScience|

#habitable-zones #life-beyond-solar-system #planetary-systems

science-and-technology3 years ago•3 min saved

"Exploring E.T.'s Potential: Dyson Spheres and Red Dwarfs"

Astronomer Erik Zackrisson and his team at Uppsala University in Sweden are studying the possibility of detecting Dyson spheres, hypothetical megastructures that harness the energy of stars, around red dwarf stars. Red dwarfs make up 75% of the stars in the Milky Way and have estimated lifetimes that can span the age of the universe. By analyzing stellar catalogs, Zackrisson and his team have identified 10 faint red dwarf stars as potential candidates for harboring Dyson spheres. Detecting these structures is challenging, as they would appear dim in the optical and bright in the infrared. However, the research has the potential to advance our understanding of astrophysics and could provide insights into the existence of advanced alien civilizations.

via Forbes|

#alien-life #astro-engineering #astronomy

science3 years ago•3 min saved

"Potential for Life on One-Third of Milky Way Planets and Beyond"

A new study suggests that about one-third of planets orbiting red dwarf stars in our Milky Way galaxy may hold conditions to support life. The study found that a third of planets orbiting red dwarf stars could be in what scientists call the “habitable zone,” meaning they have temperatures that could permit liquid water to exist on the surface. The researchers measured the “eccentricity” of more than 150 exoplanets orbiting red dwarf stars and found that the Milky Way may have hundreds of millions of planets that could be studied for possible signs of life.

via VOA Learning English|

#exoplanets #habitable-zone #liquid-water

astronomy3 years ago•5 min saved

Small red stars lack Jupiter-sized planets.

A new study has found that Jupiter-like planets are rare around small red dwarf stars, which are the most common type of star in the universe. This could have implications for the development of Earth-like planets and the search for alien life. The study examined 200 small red dwarfs and found no Jupiter-equivalent planets, suggesting that rocky planets around red dwarfs may not have evolved into Earth-like, life-friendly places. However, the absence of Jupiter-like planets means more raw material should be available for building up smaller, rocky bodies, potentially leading to rich habitability possibilities.

via Phys.org|

#astronomy #exoplanets #habitable-planets