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Categories: Geoscience: Geomagnetic Storms, Space: Astrophysics
Published A star's unexpected survival


Hundreds of millions of light-years away in a distant galaxy, a star orbiting a supermassive black hole is being violently ripped apart under the black hole's immense gravitational pull. As the star is shredded, its remnants are transformed into a stream of debris that rains back down onto the black hole to form a very hot, very bright disk of material swirling around the black hole, called an accretion disc. This phenomenon -- where a star is destroyed by a supermassive black hole and fuels a luminous accretion flare -- is known as a tidal disruption event (TDE), and it is predicted that TDEs occur roughly once every 10,000 to 100,000 years in a given galaxy.
Published When migrating birds go astray, disturbances in magnetic field may be partly to blame


Disturbances to Earth's magnetic field can lead birds astray -- a phenomenon scientists call 'vagrancy' -- even in perfect weather, and especially during fall migration. While other factors such as weather likely play bigger roles in causing vagrancy, researchers found a strong correlation between birds that were captured far outside of their expected range and the geomagnetic disturbances that occurred during both fall and spring migrations.
Published The world in grains of interstellar dust


Understanding how dust grains form in interstellar gas could offer significant insights to astronomers and help materials scientists develop useful nanoparticles.
Published Researchers measure size-luminosity relation of galaxies less than a billion years after Big Bang


A team has studied the relation between galaxy size and luminosity of some of the earliest galaxies in the universe taken by the James Webb Space Telescope, less than a billion years after the Big Bang.
Published Hubble finds hungry black hole twisting captured star into donut shape


Black holes are gatherers, not hunters. They lie in wait until a hapless star wanders by. When the star gets close enough, the black hole's gravitational grasp violently rips it apart and sloppily devours its gasses while belching out intense radiation. Astronomers have recorded a star's final moments in detail as it gets gobbled up by a black hole.
Published How do rocky planets really form?


A new theory could explain the origin and properties of systems of rocky super-Earths and their relationship with the terrestrial planets of the solar system.
Published How did the Butterfly Nebula get its wings? It's complicated


Something is amiss in the Butterfly Nebula. When astronomers compared two exposures of this planetary nebula that had been taken by the Hubble Space Telescope in 2009 and 2020, they saw dramatic changes in the material within its 'wings.' Powerful winds are apparently driving complex alterations of material within the Butterfly Nebula, behavior not seen in planetary nebulae to date. The researchers want to understand how such activity is possible from what should be a 'sputtering, largely moribund star with no remaining fuel.'
Published New study models the transmission of foreshock waves towards Earth


As the supersonic solar wind surges towards Earth, its interaction with our planet's magnetic field creates a shock to deflect its flow, and a foreshock filled with electromagnetic waves. How these waves can propagate to the other side of the shock has long remained a mystery.
Published Ultrathin solar cells promise improved satellite performance


As low Earth orbit becomes more cluttered, it becomes increasingly necessary to use middle Earth orbits, and radiation-tolerant cell designs will be needed. Making photovoltaics thinner should increase their longevity because the charge carriers have less far to go during their shortened lifetimes. Scientists propose a radiation-tolerant photovoltaic cell design that features an ultrathin layer of light-absorbing material. Compared to thicker cells, nearly 3.5 times less cover glass is needed for the ultra-thin cells to deliver the same amount of power after 20 years of operation.
Published Where do high-energy particles that endanger satellites, astronauts and airplanes come from?


Astrophysicists show how and when specific particles form and offers clues to questions that have troubled scientists since the 1940s.
Published Major infrared breakthrough could lead to solar power at night


Using technology similar to night-vision goggles, researchers have developed a device that can generate electricity from thermal radiation.
Published Modeling Earth's magnetosphere in the laboratory


Scientists report a method to study smaller magnetospheres, sometimes just millimeters thick, in the laboratory. The new experimental platform combines the magnetic field of the Large Plasma Device with a fast laser-driven plasma and a current-driven dipole magnet. The LAPD magnetic field provides a model of the solar system's interplanetary magnetic field, while the laser-driven plasma models the solar wind and the dipole magnet provides a model for the Earth's inherent magnetic field. Motorized probes allow system scans in three dimensions by combining data from tens of thousands of laser shots.
Published Researchers discover source of super-fast electron 'rain'


Scientists have discovered a new source of super-fast, energetic electrons raining down on Earth's atmosphere, a phenomenon that contributes to the colorful aurora borealis and poses hazards to satellites, spacecraft and astronauts.
Published Ancient ice reveals mysterious solar storm


Through analysis of ice cores from Greenland and Antarctica, a research team has found evidence of an extreme solar storm that occurred about 9,200 years ago. What puzzles the researchers is that the storm took place during one of the sun's more quiet phases -- during which it is generally believed our planet is less exposed to such events.
Published A lab in the sky: Physics experiment in Earth’s atmosphere could help improve GPS performance


The Earth's atmosphere has been used as a 'laboratory' to carry out a physics experiment which could help to improve the performance of GPS.
Published Protecting Earth from space storms


A major space weather event could have a catastrophic impact on Earth, disabling communications and electrical systems. Researchers are using the Frontera supercomputer to develop new geomagnetic forecasting methods and improve the Geospace Model used by NOAA for operational purposes. They hope to increase the lead time for space weather events from 30 minutes to 1-3 days, localize space weather forecasts, and provide uncertainty estimates.
Published Solving solar puzzle could help save Earth from planet-wide blackouts


Understanding the Sun's magnetic dynamo could help predict solar weather, such as potentially dangerous geothermal storms, solar flares and sunspots. Mathematicians have proposed a new model of the Sun that matches observed data.
Published Unravelling the knotty problem of the Sun's activity


A new approach to analysing the development of magnetic tangles on the Sun has led to a breakthrough in a longstanding debate about how solar energy is injected into the solar atmosphere before being released into space, causing space weather events. The first direct evidence that field lines become knotted before they emerge at the visible surface of the Sun has implications for our ability to predict the behavior of active regions and the nature of the solar interior.
Published Lightning impacts edge of space in ways not previously observed


A team of researchers working with data collected by an Incoherent Scatter Radar (ISR) have examined the simultaneous impacts of thunderstorms and solar flares on the ionospheric D-region (often referred to as the edge of space).
Published Boundary of heliosphere mapped


For the first time, the boundary of the heliosphere has been mapped, giving scientists a better understanding of how solar and interstellar winds interact.