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       From-  Sky & Telescope    By - Bob King    Edited by - Amal Udawatta Comet ATLAS exhibits a bright coma and short dust tail pointing southwest on December 15th. At the time it was magnitude 8.1 and 19° from the Sun. Nick James, BAA Comet ATLAS (C/2024 G3) is on its way! Discovered April 5th by the automated  Asteroid Terrestrial-impact Last Alert System  (ATLAS) when it was magnitude 19 and 4.4 astronomical units from Earth, it's now visible at 8th magnitude in Scorpius at dawn for observers at equatorial and southern latitudes. Hang tight. The future looks bright for this latest visitor from afar. The comet's position along its orbit — gray below the ecliptic plane and white above it — is shown for December 18th. It makes a hairpin curve around the Sun at perihelion on January 13th, during which time it will rapidly brighten and then just as quickly fade. NASA / JPL   with additions by Bob King Arriving at perihelio...

    From - Sky & Telescope   By - Joe Rao   Edited by - Amal Udawatta     Constant Contact Use. Please leave this field blank. In the coming weeks, Jupiter’s four Galilean satellites will arrange themselves in some unusual geometric patterns that will be fascinating to observe. Jupiter’s four  Galilean satellites  are always fun to watch as they change position relative to each other from night to night and even hour to hour. Galileo originally assigned  Roman numerals  to these moons, based on the amount of time each took to revolve around Jupiter. However, the mythological names that we use today were chosen by Galileo’s rival,  Simon Marius , who claimed that he discovered the four moons about a month before Galileo did. Io (I), the innermost of this quartet, takes only 1.8 days to make one revolution around Jupiter. Europa (II) takes twice as long at 3.6 days, while Ganymede (III) circles Jupiter in 7.2 days — exactly four t...

  From - Sky & Telescope By - Colin Stuart Edited by - Amal Udawatta Constant Contact Use. Please leave this field blank. False-color views of the face-on circumstellar disk around Vega from the Hubble (left) and Webb (right) space telescopes. In both images, light from the star itself has been subtracted to create the dark spot at the center. The disk is very smooth, with no evidence of embedded large planets. NASA / ESA / CSA / STScI / S. Wolff, K. Su, A. Gáspár (University of Arizona) Vega, the stellar standout of the constellation Lyra, the Lyre, has long intrigued astronomers. It is one of the brightest stars in the sky, and the glow of all other is measured against it. To say that the circumstellar disk around Vega is vast would be an understatement — it spans about 100 billion miles. That’s more than 1,000 times Earth’s distance from the Sun. High-resolution images reveal the debris disk around Lyra’s brightest star to be exceedingly smooth. If any planets lurk therein, ...

  From - Sky & Telescope Camille M. Carlisle   By - Camille M. Carlisel  Edited by Amal Udawatta  Constant Contact Use. Please leave this field blank. Artist's concept of the V404 Cygni system, in which a black hole is stealing gas from a nearby star. Astronomers had thought the system was only a binary, but a second star (upper white flash) orbits at a much farther distance. Jorge Lugo The system V404 Cygni is an old favorite with astronomers. The binary contains a 9-solar-mass black hole that’s slurping gas from a star slightly less massive than the Sun. Astronomically speaking, only a hair’s breath separates the pair: 0.14 astronomical unit, or less than half Mercury’s average distance from the Sun. (This is normal for these kinds of systems.) The hot gas swirling down onto the black hole creates an X-ray beacon. In fact, V404 Cygni was the first system of its kind — called a  low-mass X-ray binary , or LMXB, where the “low mass” refers to the companion s...

      From - Sky & telescope  By- Govert Schilling  Edited by - Amal Udawatta     Using the CHIME radio telescope, astronomers detected a three-second flash from a far-off galaxy that contained beat with a surprising regularity. Photo courtesy of CHIME, with background edited by MIT News Exotic magnetars make brief, powerful flashes of radio waves — but a new discovery suggests there may be more than one way to make a magnetar. For the first time ever, astronomers have detected a  fast radio burst  (FRB) in a large elliptical galaxy. The discovery, announced at the FRB2024 conference in Khao Lak, Thailand, supports earlier indications that there are various ways to form the extreme objects that produce these ultra-brief flashes of radio waves. Astronomers first discovered fast radio bursts in 2007, and more than 800 have been observed to date (see S&T’s  September 2022  issue). In just one-thousandth of a second, they radiat...

     From- Sky &Telescope    By - Monica Young    Edited by - Amal Udawatta This artist’s illustration shows a disk of material (red, orange, and yellow) created after a supermassive black hole (depicted on the right) destroyed a star through intense tidal forces. After a few years, this disk expanded outward until it began intersecting another orbiting object — either a star or a small black hole — around the giant black hole. NASA / CXC / SAO and Soheb Mandhai / The Astro Phoenix In 2019 a supermassive black hole ate a star. It’s incredible that such an incredible event is now commonplace — not in individual galaxies, where such stellar meals happen only every 10,000 to 100,000 years, but in our telescopes, through which astronomers can monitor millions of galaxies to observe their feeding habits.      The crumbs of a supermassive black hole’s stellar meal has revealed the presence of a second star in a close orbit. But in the cour...

        From - Sky & Telescope    By- AAS NOVA    Edited -  Amal Udawatta    A 1995 Hubble Space Telescope image of the brown dwarf Gliese 229 B next to its far brighter host star, the M dwarf Gliese 229 A. S. Kulkarni (Caltech), D.Golimowski (JHU) and NASA Astronomers recently discovered a companion to Gliese 229 B, the first confidently identified brown dwarf. This discovery resolves the conflict between Gliese 229 B’s observed mass and the predictions of evolutionary models, potentially illuminating the nature of other poorly understood brown dwarf systems as well. An illustration of a brown dwarf. Brown dwarfs aren’t actually brown, likely spanning a range of colors from reddish-orange to nearly black. NASA / JPL-Caltech In 1995, Gliese 229 B became the first object to be unambiguously classified as a brown dwarf: an object that bridges the gap between planets and stars. At roughly 13–80 times the mass of Jupiter, brown dwar...