Jim CareyNASA's Chandra Finds Young Stars Dim Quickly https://www.nasa.gov/image-detail/dimming-lg/?utm_source=dlvr.it&utm_medium=mastodon #NASA #ChandraObservatory #YoungStars #Astronomy #SpaceDiscovery
Daniel FischerX-ray Evolution of Young Stars - Early Dimming and Coronal Softening in Solar-Mass Stars with Implications for Planetary Atmospheres: https://arxiv.org/abs/2512.12055 -> NASA Finds #YoungStars Dim in X-rays Surprisingly Quickly: https://chandra.si.edu/press/26_releases/press_041426.html and https://chandra.cfa.harvard.edu/photo/2026/dimming/
X-ray Evolution of Young Stars: Early Dimming and Coronal Softening in Solar-Mass Stars with Implications for Planetary Atmospheres
X-ray and ultraviolet (XUV) emission from young stars plays a critical role in shaping the evolution of planetary atmospheres and the conditions for habitability. To assess the long-term impact of high-energy stellar radiation, it is essential to empirically trace how X-ray luminosities and spectral hardness evolve during the first ~<1 Gyr, when atmospheric loss and chemical processing are most active. This study extends the X-ray activity-mass-age analysis of <25 Myr stars by Getman et al. (2022) to ages up to 750 Myr, using Gaia-based cluster memberships, new Chandra observations of five rich open clusters (~45--100 Myr), and archival ROSAT and Chandra data for three older clusters (~220--750 Myr). We find a mass-dependent decay in X-ray luminosity: solar-mass stars undergo a far more rapid and sustained decline, accompanied by coronal softening and the disappearance of hot plasma by ~100 Myr, compared to their lower-mass siblings. These trends in solar-mass stars are likely linked to reduced magnetic dynamo efficiency and diminished ability to sustain large-scale, high-temperature coronal structures. The trends are significantly stronger than predicted by widely used XUV-rotation-age relations. The revised trends imply systematically lower rates of atmospheric mass loss and water photolysis, as well as altered ionization environments and chemical pathways relevant to the formation of prebiotic molecules, for planets in close orbits around solar analogs. These effects persist throughout at least the ~<750 Myr interval probed in this study.
NewsletterTFThe Architecture of Absence: Why Hollywood’s Minors Exit the Frame
Why do young actors leave Hollywood? Many quit acting before 18 for education, stable jobs, and privacy. Learn about their reasons and new careers.
#ChildActors, #HollywoodExit, #YoungStars, #CareerChange, #StableJobs
https://newsletter.tf/child-actors-quit-hollywood-stable-jobs-before-18/
Many young stars are leaving Hollywood before they turn 18. They are choosing normal jobs like teaching or real estate instead of acting.
#ChildActors, #HollywoodExit, #YoungStars, #CareerChange, #StableJobs
https://newsletter.tf/child-actors-quit-hollywood-stable-jobs-before-18/
Celebrity Origins: Pre-Fame Portraits Unveiled
See pictures of famous people like Taylor Swift and Leonardo DiCaprio when they were young. Learn about their early jobs and lives before fame.
#CelebrityPhotos, #BeforeTheyWereFamous, #FamousPeople, #YoungStars, #CelebrityOrigins
New photos show famous stars like Taylor Swift and Leonardo DiCaprio when they were teenagers. Many had normal jobs before becoming famous.
#CelebrityPhotos, #BeforeTheyWereFamous, #FamousPeople, #YoungStars, #CelebrityOrigins
Dr. Juande Santander-VelaTeams using our ALMA Observatory have been able to clearly show how magnetism has a pre-eminent role in young star accretion and growth!
The best part is that the lead scientist for that paper is our colleague Paulo Cortés, who apart from doing notable science is also responsible for the scientific acceptance of ALMA software releases!
#ALMA #AtacamaLargeMillimeterArray #AtacamaLargeMillimeterSubmillimeterArray #YoungStars #StarFormation #Magnetism #CosmicMagnetism
Astronomers Spot Magnetically-Guided Streamer Funneling Star-Building Material into Newborn System in Perseus | ALMA Observatory
New ALMA observations reveal spiral-shaped gas streamer guided by magnetic fields in a star-forming nursery Highlights A team of astronomers led by Paulo Cortes, a scientist with the U.S. National Science Foundation National Radio Astronomy Observatory and the Joint ALMA Observatory, has made a groundbreaking discovery about how young star systems grow. Using the powerful...
Dr. Juande Santander-VelaOf course all of this builds on the initial success from the original ALMA long-baseline campaing that looked at HL Tau and found its protoplanetary disk in all its glory…
#ALMA #AtacamaLargeMillimeterSubmillimeterArray #AtacamaLargeMillimeterArray #ProtoplanetaryDisks #PlanetFormation #YoungStars #YoungSolarSystems #HLTau
Revolutionary ALMA Image Reveals Planetary Genesis | ALMA Observatory
A new image from ALMA, the Atacama Large Millimeter/submillimeter Array, reveals extraordinarily fine detail that has never been seen before in the planet-forming disc around a young star. ALMA’s new high-resolution capabilities were achieved by spacing the antennas up to 15 kilometers apart[1. Since September 2014 ALMA has been observing the Universe using its longest...
Using data from ALMA and advanced simulations, a research team led by Santiago Orcajo from the Instituto de Astrofísica de La Plata in Argentina (CONICET and Universidad Nacional de La Plata) has presented a new model that traces the evolution of protoplanetary disks through five distinct stages. The results strongly support a planet-driven origin of these substructures and offer new insights into how planets interact with the disks in which they form.
Stage I: Very young disks with shallow or no obvious substructures, corresponding to an epoch in which protoplanets are not massive enough to carve noticeable gaps in the disks.
Stage II: Disks with relatively narrow, but clear gaps and rings, indicating the growth of protoplanets
Stage III: A rapid widening of the gaps due to the sudden growth in the mass of some planets when they acquire their gaseous envelopes. This stage includes the rapid accumulation of dust at the outer edges of the gaps (the inner rims of the outer disks) due to the strong “pressure bumps” caused by the giant planets that recently formed, which stops the inward drift of dust.
Stage IV: Dust filtration at the edges of the cavities, resulting in dust-depleted inner disks. The millimeter dust from the outer disks efficiently drifts in and accumulates at the edges of the gaps.
Stage V: Eventually, the dusty inner disks drain completely onto the stars, and the outer disks become narrow rings (or collections of narrow rings).
#ALMA #AtacamaLargeMillimeterSubmillimeterArray #AtacamaLargeMillimeterArray #ProtoplanetaryDisks #PlanetFormation #YoungStars #YoungSolarSystems
ALMA Inspires New Models for the Evolution of Planet-Forming Disks | ALMA Observatory
By combining ALMA observations and simulations, the ODISEA team traces how planets may form and reshape their disks Ever since ALMA captured the striking image of HL Tau in 2014, revealing intricate rings and gaps in a disk around a newborn star, astronomers have sought to understand how such complex structures could emerge so early. The...
An international collaboration called exoALMA is using our telescopes to s peer through the dusty disks where planets are born. Thanks to their newly developed advanced imaging techniques, exoALMA has revealed the most sharp images of young solar systems, as never seen before. This research project has just published 17 papers, with several more coming on the several months.
The exoALMA collaboration is using ALMA to conduct a comprehensive planet hunting campaign in the sub-mm regime. They claim to be the first to focus on still-forming planets, instead of fully formed ones.
Unlike traditional planet-hunting methods that look for a young planet's direct light, exoALMA looks for the effects planets have on their surroundings. This approach potentially allows to detect much younger planets than ever before. "It's like trying to spot a fish by looking for ripples in a pond, rather than [the] fish itself.”
More information on the link below:
#ALMA #AtacamaLargeMillimeterSubmillimeterArray #AtacamaLargeMillimeterArray #exoALMA #ExoPlanets #YoungStars #StarFormation #PlanetFormation #YoungPlanets
ExoALMA survey reveals incredible images of structures in protoplanetary disks | ALMA Observatory
An international scientific team have embarked on an exciting new project to hunt for planets forming around young stars. The exoALMA project, using the powerful Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, is peering into the dusty disks where planets are born. Thanks to newly developed advanced imaging techniques, exoALMA has revealed the most sharp...