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Fastest-known star zooms under Milky Way black hole's influence

Fastest-known star zooms under Milky Way black hole's influence

WASHINGTON, Aug 19 (Reuters) - Scientists have detected the fastest-known star, a stellar speedster that is zooming around the supermassive black hole residing at the center of our galaxy and might hold the key to measuring the spin of this celestial beast for the first time.

Telescope spies the fastest star in the Milky Way zipping around a black hole

Telescope spies the fastest star in the Milky Way zipping around a black hole

A telescope has spotted the fastest known star in the Milky Way

James Webb Space Telescope Detects Water Molecules Near Milky Way's Central Black Hole

James Webb Space Telescope Detects Water Molecules Near Milky Way's Central Black Hole

Astronomers using the James Webb Space Telescope (JWST) have detected water molecules and silicate dust around IRS 3, a giant star located only 0.55 light-years from Sagittarius A*, the Milky Way’s central black hole. This discovery, detailed in a study by Florian Peißker and colleagues in Astronomy & Astrophysics, demonstrates that dust production and molecular material can persist in the intense radiation environment surrounding a supermassive black hole. The region around Sagittarius A* is characterized by extreme radiation, powerful winds, and gravitational stress, making the survival of fragile molecules like water a significant puzzle. IRS 3, a 72-million-year-old star with about six times the Sun's mass, is nearing the end of its life and shedding layers of gas and dust. The JWST's Mid-Infrared Instrument (MIRI) provided the most complete infrared spectrum for IRS 3 to date, confirming its oxygen-rich, silicate-based composition and, notably, the presence of water molecules. The research team sugges...

Hubble Space Telescope Uncovers Evidence of Ancient Galactic Collision Transforming Milky Way

Hubble Space Telescope Uncovers Evidence of Ancient Galactic Collision Transforming Milky Way

The Hubble Space Telescope has provided evidence of a significant collision and merger between our Milky Way galaxy and a dwarf galaxy, named LKH, approximately 11.8 billion years ago. This discovery, reported in the journal Nature Astronomy by lead author Davide Massari, indicates that the Milky Way's early evolution was influenced by stars originating from external galaxies, challenging previous assumptions that its earliest phases were solely defined by stars born within the galaxy itself. Researchers identified a third population of globular clusters that are neither native to the Milky Way nor from the previously known Gaia–Sausage–Enceladus (GSE) merger, which occurred about 10 billion years ago. These newly identified clusters arrived before the GSE merger, suggesting an even earlier and impactful galactic event. The LKH dwarf galaxy is estimated to have had a total mass of 500 million times the mass of our sun, contributing a substantial amount of stars, gas, and dark matter to the then-smaller Mil...

Astronomers Discover First Three-Lobed Asteroid, Nysa, Challenging Formation Models

Astronomers Discover First Three-Lobed Asteroid, Nysa, Challenging Formation Models

An international team of astronomers, led by Kate Minker of Lowell Observatory, has identified asteroid (44) Nysa as the first confirmed three-lobed asteroid ever imaged. This discovery, detailed in their paper 'Unmasking (44) Nysa: Evidence for a Trilobate Structure' posted on arXiv, challenges previous assumptions about asteroid formation. Until now, all known asteroids with distinct 'necks' or narrow waists, formed by the accumulation of smaller bodies, were observed to have exactly two lobes. Nysa, a 75-kilometer body in the main asteroid belt, was found to have two prominent valleys wrapping around its circumference, effectively dividing it into three connected sections. The observations were made using ground-based instruments, SHARK-VIS on the Large Binocular Telescope in Arizona and SPHERE/ZIMPOL on the European Southern Observatory’s Very Large Telescope in Chile, which employ adaptive optics to achieve spacecraft-quality imaging resolution from Earth. Additionally, the team discovered a small moo...

Hubble and Gaia Telescopes Uncover Evidence of Ancient Milky Way Merger, Extending Galactic History by 1.8 Billion Years

Hubble and Gaia Telescopes Uncover Evidence of Ancient Milky Way Merger, Extending Galactic History by 1.8 Billion Years

New data from the NASA/ESA Hubble Space Telescope, combined with information from ESA’s Gaia mission, has provided definitive evidence of a dwarf galaxy merging with the young Milky Way galaxy in its earliest evolutionary phases. This discovery pushes back the known history of our galaxy by 1.8 billion years. Researchers studied 39 globular clusters within the inner 20,000 light-years of the Milky Way, which are ancient star collections that act as 'cosmic archaeological sites.' By analyzing the age and metal content of these clusters, scientists identified a third population of globular clusters. These clusters are older than those from the Gaia-Sausage-Enceladus merger (10 billion years ago) but younger than those originally formed in the Milky Way. This indicates they originated from an even earlier merger, approximately 11.8 billion years ago, just 2 billion years after the Big Bang. The dwarf galaxy involved in this merger has been named Low-energy-Kraken-Heracles (LKH) and contained roughly 500 milli...

Astronomers Detect Gravitational Lensing of Blazar Jet by Unseen Dark Matter Cluster

Astronomers Detect Gravitational Lensing of Blazar Jet by Unseen Dark Matter Cluster

Astronomers have found evidence that a plasma jet emanating from the distant blazar PKS 2233-148 has been gravitationally lensed. This phenomenon, predicted by Albert Einstein's theory of general relativity, occurs when a massive object warps space, altering the path of light. In this specific case, researchers observed a sudden deviation in the jet's expected trajectory and peculiarities in its gamma-ray curve. The blazar PKS 2233-148 is a type of quasar where supermassive black holes are surrounded by vast amounts of matter, with some material being ejected as plasma jets directed towards Earth. The team, led by Silke Britzen, reanalyzed data from the Very Long Baseline Array, the Fermi space telescope, and the Swift space observatory to track the jet's motion over time. The absence of any visible massive object, such as a galaxy or galaxy cluster, in the position to cause this lensing effect suggests that an invisible cluster of dark matter is responsible. Dark matter does not interact with electromagne...

Hubble Space Telescope Reveals Ancient Galactic Collision Transformed Milky Way

Hubble Space Telescope Reveals Ancient Galactic Collision Transformed Milky Way

The Hubble Space Telescope has provided evidence of a significant collision and merger between our Milky Way galaxy and a dwarf galaxy, named LKH, approximately 11.8 billion years ago. This event occurred just two billion years after the Big Bang, when the Milky Way was considerably smaller. Researchers, led by Davide Massari of the Astrophysics and Space Science Observatory of Bologna, identified a third population of globular clusters that are neither native to the Milky Way nor associated with the previously identified Gaia–Sausage–Enceladus (GSE) galaxy merger, which happened about 10 billion years ago. These newly discovered clusters are believed to have originated from LKH. The team calculated LKH's total mass to be 500 million times that of our sun, a substantial contribution to the early Milky Way's mass, including stars, gas, and dark matter. This discovery adds a crucial event to the Milky Way's evolutionary timeline, predating the GSE merger.

JWST Detects Water and Dust Near Milky Way's Supermassive Black Hole

JWST Detects Water and Dust Near Milky Way's Supermassive Black Hole

The James Webb Space Telescope (JWST) has detected water, dust, and other oxygen-based chemical products in the vicinity of the Milky Way's supermassive black hole, Sagittarius A*. This discovery was made by observing a dying star named IRS 3, an asymptotic giant branch (AGB) star, located just 0.55 light-years from the galactic center. IRS 3 is in a late stage of its life, shedding its outer layers into space at high speeds, creating an immense dusty envelope. Astronomers, led by Florian Peißker, an astrophysicist at the University of Cologne, utilized JWST's Mid-Infrared Instrument (MIRI) to collect a continuous mid-infrared spectrum from IRS 3. This allowed them to identify silicate dust and the star's chemical composition, demonstrating that stars can continue to enrich their surroundings with molecular material even in extreme environments dominated by intense radiation.

Star Near Milky Way's Black Hole Losing Mass at Astonishing Rate, Reveals JWST

Star Near Milky Way's Black Hole Losing Mass at Astonishing Rate, Reveals JWST

New observations from the James Webb Space Telescope (JWST) indicate that IRS 3, a mature star located near the Milky Way's supermassive black hole, Sagittarius A* (Sgr A*), is undergoing an exceptionally rapid phase of mass loss. This star is shedding vast amounts of gas and dust into space, causing its surrounding envelope to continuously expand. Researchers, led by PD Dr. Florian Peißker of the University of Cologne’s Institute for Astrophysics, utilized JWST’s Mid-Infrared Instrument (MIRI) to study IRS 3, which is approximately 0.6 light-years from Sgr A*. The findings, published in the journal Astronomy & Astrophysics, suggest that IRS 3 is experiencing a 'superwind,' a period of extreme mass loss near the end of a massive star's life. The star is estimated to be losing material equivalent to Earth's mass every 18 days, contributing to the unusual size and density of its envelope. Surprisingly, water molecules were detected within this harsh environment, challenging previous assumptions about molecul...

Hubble and Gaia Telescopes Uncover Ancient Galactic Collision That Transformed the Milky Way

Hubble and Gaia Telescopes Uncover Ancient Galactic Collision That Transformed the Milky Way

New data from the NASA/ESA Hubble Space Telescope, combined with measurements from ESA's Gaia mission, has provided definitive evidence of an ancient collision between the young Milky Way galaxy and a dwarf galaxy named LKH (Low-energy–Kraken–Heracles) approximately 11.8 billion years ago. This event, occurring just 2 billion years after the Big Bang, predates previously identified major mergers in the Milky Way's history, such as the collision with the Gaia–Sausage–Enceladus (GSE) galaxy 10 billion years ago. Researchers identified a third population of globular clusters within the Milky Way that are neither native to our galaxy nor from the GSE merger. By precisely measuring the age and metal content of these clusters, scientists determined they originated from LKH, a dwarf galaxy with a total mass of about 500 million times the mass of our sun, which was a significant fraction of the Milky Way's mass at that early stage.

James Webb Space Telescope Identifies 'Black Hole Star' MoM-BH-1, Challenging Early Universe Formation Theories

James Webb Space Telescope Identifies 'Black Hole Star' MoM-BH-1, Challenging Early Universe Formation Theories

Astronomers utilizing the James Webb Space Telescope (JWST) have identified a unique celestial object, MoM-BH-1, which they've dubbed a 'black hole star.' This object, observed from approximately 660 million years after the Big Bang, appears as an unusually bright red dot. Led by astronomer Rohan P. Naidu, the research, published in Nature, suggests MoM-BH-1 is a black hole encased within an extraordinarily dense, turbulent envelope of hydrogen gas, roughly the size of our solar system. This configuration allows the black hole to generate energy at a scale 100 billion times greater than a typical star, mimicking stellar features despite its non-fusion energy source. The discovery was made during the 'Mirage or Miracle' (MoM) survey, which aimed to study luminous galaxies from the early universe. MoM-BH-1's distinct spectral characteristics, particularly a strong Balmer break and hydrogen features, led researchers to model it as an actively feeding black hole surrounded by a vast gas cocoon, rather than a c...