Astro Blog

By MICHAEL GRESHKO , Science.  Excerpt: Earth got its bell rung this past weekend, sucker-punched by the Sun itself in the biggest geomagnetic storm in more than 2 decades. The storm—triggered when the magnetic fields in blobs of plasma from the Sun collided with Earth’s magnetic field—not only yielded once-in-a-generation aurorae at latitudes as low as the Florida Keys, but also took scientists’ breath away with its power. ...This weekend’s fireworks began with Active Region 3664, a giant cluster of sunspots, more than 15 times wider than Earth, where the Sun’s magnetic field is highly concentrated. The magnetic field lines twisted and eventually snapped, causing the cluster to fling off a series of enormous, billion-ton blobs of plasma toward Earth, each embedded with strong magnetic fields. The detection of at least five of these expulsions, known as coronal mass ejections (CMEs), caused U.S. forecasters to  issue a “severe” G4 watch —its first since 2005—on 9 May, the day ...

https://eos.org/research-spotlights/protecting-power-grids-from-space-weather By Rachel Fritts , Eos/AGU.  Excerpt: Activity from the Sun, such as  solar flares , can cause fluctuations in Earth’s geomagnetic field that send electrical currents flowing through power grids. These  geomagnetically induced currents  (GICs) can cause problems ranging from temporary voltage instability to widespread blackouts to reduced life spans for transformers. It is therefore important to develop effective mitigation strategies that protect against GIC-induced power disruptions while maintaining power to consumers. Suggested solutions have included installing equipment such as capacitors to block GICs and making changes to network configurations.  Mac Manus et al .  worked with the energy company Transpower New Zealand Ltd. to test four mitigation strategies that could be used throughout the North and South Islands of New Zealand. The team did this by ...modeling potential ...