Latest news with #magneticfields
Yahoo
18-07-2025
- Science
- Yahoo
Scientists Just Solved a Solar Mystery That Baffled Humanity For Centuries
Here's what you'll learn when you read this story: Why sunspots are able to last so long has been a mystery for millenia, but a new observation technique revealed their secret. The equilibrium between magnetic fields and pressure allows the solar blotches to remain stable anywhere from days to months. Despite being darker, cooler regions of the sun, sunspots are related to its hot temper, and can help predict solar outbursts like flares and coronal mass ejections. Sunspots were observed on the surface of our star centuries before Galileo suffered eye damage peering at them through his telescope. The first known records were written down by Chinese astronomers in 27 B.C., but observation may go even further back if Greek philosopher Anaxagoras really, ahem, spotted one in 467 B.C. While some of the ancients thought that these shadows on our star meant changes in the cosmos, sunspots are surprisingly stable—and now we know why. Sunspots are actually byproducts of magnetic field chaos. Inside the sun's convective zone, scorching plasma cools as it moves towards the solar surface, taking energy with it. This plasma becomes denser as it loses heat and sinks, forming cooler dark spots until heat from further inside the sun causes it to rise again. And all the while, magnetic fields keep twisting and breaking and rearranging themselves. This explains the association of sunspots with the outbursts we know as solar flares and coronal mass ejections, which can release enough electromagnetic radiation to threaten satellites and electrical infrastructure on Earth. More stable sunspots can possibly give more insight to the solar activity cycle, which is about 11 years long and peaks during a solar maximum. Previous explanations for their stability suggested an equilibrium between magnetic fields and gas pressure, but magnetic turmoil has long made this difficult to observe. Now, an international research team using Germany's GREGOR solar telescope has finally cleared up the hazy observations of sunspots with a new method that removes interference from Earth's atmosphere and reveals strikingly clear images. Led by researchers from the Institute of Solar Physics in Freiburg, Germany, the technique—originally developed at the Göttingen Max Planck Institute for Solar System Research—has achieved what only (much more expensive) satellites were able to do before: it made the analysis of polarized light from the Sun possible. Polarization is the phenomenon of light's electric field moving back and forth, perpendicular to the direction in which the light wave itself is headed, and light is said to be polarized when it continues to propagate one way (as opposed to scattering). By taking a closer look at polarized light, the team was able to tell exactly where it was coming from within sunspots, and what was going on inside. It turned out that the equilibrium in sunspots is a balance of pressure and magnetism. Magnetic fields are strongest when electrons remain unattached, but as more pressure is exerted, it forces them into pairs and weakens the magnetic field. Just enough pressure balances out the strength of magnetic fields and keeps the sunspots intact for extended periods. This is known as magnetohydrostatic equilibrium, which describes the properties of a gas or fluid (such as solar plasma) in a magnetic field. Because solar plasma can conduct electricity, it supports the magnetic field it interacts with. '[Our] results provide decisive observational and theoretical support for the idea that sunspots slowly evolve around an equilibrium state and are [in] magnetohydrostatic equilibrium, thereby helping to explain their long lifespans,' the researchers said in a study recently published in Astronomy & Astrophysics. Understanding why sunspots—and the solar turbulence that comes with them—can hang around for so long will help us better forecast space weather and possibly prevent blackouts, damage to satellites, and threats to astronauts' health. You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life? Solve the daily Crossword
Forbes
04-06-2025
- General
- Forbes
In Photos: Sharpest-Ever Views Of The Sun's Surface Reveal ‘Stripes'
Scientists using the world's biggest solar telescope in Hawaii have captured the sharpest-ever view of the sun's surface. In doing so, they've identified super-fine 'stripes' and 'magnetic curtains' on the sun for the first time, which could help in understanding how the sun behaves — and how its energetic events can threaten Earth. It comes in the wake of the same telescope's spectacular image of a planet-sized cluster of sunspots covering 241 million square miles of the sun's surface, which was published in April. The Daniel K. Inouye Solar Telescope is the world's largest solar telescope, situated atop the 10,000-foot-tall Haleakalā volcano in Hawaii. A 13-foot/four-meter solar ground-based telescope, it's designed to help solar physicists investigate the physics of the sun and how it drives space weather. The ultra-fine magnetic 'stripes' observed by the DKIST are bright and dark striations that appear to be rippling across the sun. The incredible detail reveals curtain-like magnetic fields and a new layer of complexity in the sun's magnetic structure. 'We investigate the fine-scale structure of the solar surface for the first time with an unprecedented spatial resolution of just about 20 kilometers or the length of Manhattan Island,' said Dr. David Kuridze, the lead author of the study, published today in The Astrophysical Journal Letters, and a scientist at the National Solar Observatory. 'These striations are the fingerprints of fine-scale magnetic field variations.' What causes the 'stripes' are magnetic fluctuations, which only DKIST's huge 4-meter mirror can detect. 'Magnetism is a fundamental phenomenon in the universe, and similar magnetically induced stripes have also been observed in more distant astrophysical objects, such as molecular clouds,' said Dr. Han Uitenbroek, co-author of the study and an NSO scientist. A deeper understanding of how magnetism works on the sun is essential if astronomers are to understand the origin of solar flares, eruptions and coronal mass ejections — powerful events that charge up the solar wind and can cause geomagnetic storms around Earth. Approximately 93 million miles from Earth, the sun is a middle-aged star, having existed for approximately five billion years. It burns around five million tons of hydrogen fuel every second. 'This is just one of many firsts for the Inouye, demonstrating how it continues to push the frontier of solar research,' said Dr. David Boboltz, NSO Associate Director for the DKIST. 'It also underscores Inouye's vital role in understanding the small-scale physics that drive space weather events that impact our increasingly technological society here on Earth.' DKIST's stunning 'first light' images showed a close-up view of the sun's surface, revealing turbulent 'boiling' plasma across the entire star. The cell-like structures are violent motions that transport heat from the inside of the sun to its surface. Wishing you clear skies and wide eyes.
