In their interiors, stars are structured in a layered, onion-like fashion. In those with solar-like temperatures, the core is followed by the radiation zone. There, the heat from within is led outwards by means of radiation. As the stellar plasma becomes cooler farther outside, heat transport is dominated by plasma flows: hot plasma from within rises to the surface, cools, and sinks down again. This process is called convection. At the same time, the star's rotation, which depends on stellar latitude, introduces shear movements.
Late last year, news broke that the star Betelgeuse was fading significantly, ultimately dropping to around 40% of its usual brightness. The activity fueled popular speculation that the red supergiant would soon explode as a massive supernova.
But astronomers have more benign theories to explain the star's dimming behavior. And scientists at the University of Washington and Lowell Observatory believe they have support for one of them: Betelgeuse isn't dimming because it's about to explode -- it's just dusty.
PULLMAN, Wash. - Organic compounds called thiophenes are found on Earth in coal, crude oil and oddly enough, in white truffles, the mushroom beloved by epicureans and wild pigs.
Thiophenes were also recently discovered on Mars, and Washington State University astrobiologist Dirk Schulze-Makuch thinks their presence would be consistent with the presence of early life on Mars.
An international team of astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) has captured the very moment when an old star first starts to alter its environment. The star has ejected high-speed bipolar gas jets which are now colliding with the surrounding material; the age of the observed jet is estimated to be less than 60 years. These features help scientists understand how the complex shapes of planetary nebulae are formed.
A black hole, ejecting material at close to the speed of light, has been observed using e-MERLIN, the UK's radio telescope array based at Jodrell Bank Observatory.
A research team based at Oxford University used e-MERLIN, as well as the VLA and MeerKAT telescopes based in the US and South Africa respectively, to track the ejecting material over a period of months.
A young planet located 150 light-years away has given UNSW Sydney astrophysicists a rare chance to study a planetary system in the making.
The findings, recently published in The Astronomical Journal, suggest that the planet DS Tuc Ab - which orbits a star in a binary system - formed without being heavily impacted by the gravitational pull of the second star.
A massive white dwarf star with a bizarre carbon-rich atmosphere could be two white dwarfs merged together according to an international team led by University of Warwick astronomers, and only narrowly avoided destruction.
They have discovered an unusual ultra-massive white dwarf around 150 light years from us with an atmospheric composition never seen before, the first time that a merged white dwarf has been identified using its atmospheric composition as a clue.
University of British Columbia astronomy student Michelle Kunimoto has discovered 17 new planets, including a potentially habitable, Earth-sized world, by combing through data gathered by NASA's Kepler mission.
Over its original four-year mission, the Kepler satellite looked for planets, especially those that lie in the "Habitable Zones" of their stars, where liquid water could exist on a rocky planet's surface.
Scientists studying a distant galaxy cluster have discovered the biggest explosion seen in the Universe since the Big Bang.
The blast came from a supermassive black hole at the centre of a galaxy hundreds of millions of light-years away.
It released five times more energy than the previous record holder.
Professor Melanie Johnston-Hollitt, from the Curtin University node of the International Centre for Radio Astronomy Research, said the event was extraordinarily energetic.
Many satellites are in space to take photos. But a vibrating satellite, like a camera in shaky hands, can't get a sharp image. Pointing it at a precise location to take a photo or perform another task, is another important function that requires accuracy. Vedant, an aerospace engineering doctoral student at the University of Illinois at Urbana-Champaign was working on a way to eliminate vibrations on a satellite when he discovered his invention could also rotate the satellite.
The latest image published February 20, 2020 from the international Gemini Observatory showcases the striking planetary nebula CVMP 1. This object is the result of the death throes of a giant star and is a glorious but relatively short-lived astronomical spectacle. As the progenitor star of this planetary nebula slowly cools, this celestial hourglass will run out of time and will slowly fade from view over many thousands of years.
While InSight's seismometer has been patiently waiting for the next big marsquake to illuminate its interior and define its crust-mantle-core structure, two scientists, Takashi Yoshizaki (Tohoku University) and Bill McDonough (Tohoku University and University of Maryland, College Park) have built a new compositional model for Mars.
A signal originally detected by the Kepler spacecraft has been validated as an exoplanet using the Habitable-zone Planet Finder (HPF), an astronomical spectrograph built by a Penn State team and recently installed on the 10m Hobby-Eberly Telescope at McDonald Observatory in Texas. The HPF provides the highest precision measurements to date of infrared signals from nearby low-mass stars, and astronomers used it to validate the candidate planet by excluding all possibilities of contaminating signals to very high level of probability.
An international team of astronomers used two of the most powerful radio telescopes in the world to create more than three hundred images of planet-forming disks around very young stars in the Orion Clouds. These images reveal new details about the birthplaces of planets and the earliest stages of star formation.
Surprising new data from NASA's Hubble Space Telescope suggests the smooth, settled "brim" of the Sombrero galaxy's disk may be concealing a turbulent past. Hubble's sharpness and sensitivity resolves tens of thousands of individual stars in the Sombrero's vast, extended halo, the region beyond a galaxy's central portion, typically made of older stars.