Astronomers have used interferometry to create a time-lapse of the nearby star zeta Andromedae over one of its 18-day rotations that show starspots — sunspots outside our solar system. The pattern of spots on the star is very different from their typical arrangement on our Sun, challenging current theories of how stars’ magnetic fields influence their evolution.
The Earth’s magnetic field is produced by the geodynamo, the rapid motion of huge quantities of liquid iron alloy in the Earth’s outer core. A team of French researchers suggests that elastic deformation of our planet’s mantle due to tidal effects caused by the Moon — overlooked until now — transfers energy to the Earth’s outer core, keeping the geodynamo active.
The Sun’s magnetic field is responsible for everything from the solar explosions that cause space weather on Earth — such as aurorae — to the interplanetary magnetic field and radiation through which our spacecraft journeying around the solar system must travel. But even now, scientists are not sure exactly where in the Sun the magnetic field is created.
About 600 miles from Earth’s surface is the first of two doughnut-shaped electron swarms, known as the Van Allen Belts. Understanding the shape and size of the belts, which can shrink and swell in response to incoming radiation from the Sun, is crucial for protecting technology in space. A new study of data from NASA’s Van Allen Probes reveals that the story is a complex one.
A group of astronomers led by the University of Sydney has discovered strong magnetic fields are common in stars, not rare as previously thought, which will dramatically impact our understanding of how stars evolve. The findings could potentially lead to a better understanding of the Sun’s magnetic cycle, which is known to affect communication systems and cloud cover on Earth.
Using new images that show unprecedented detail, scientists have found that material rotating around a very young protostar probably has dragged in and twisted magnetic fields from the larger area surrounding the star. The discovery, made with the Very Large Array radio telescope, has important implications for how dusty discs — the raw material for planet formation — grow around young stars.
A new ice age is coming — if the prediction of a Lomonosov Moscow State University researcher and her colleagues is correct. A model that accurately predicts variations in the Sun’s magnetic field suggests a sharp decline in solar output during the years 2030-2040, producing conditions similar to that existing during the 17th century Maunder minimum.
Our Sun is a volatile star, producing giant clouds of solar particles called coronal mass ejections. Now scientists may finally have a tool to predict the magnetic configuration of a CME from afar, enabling forecasters to give utility grid and satellite operators a day’s advance warning to protect their systems.
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