EARTH-DIRECTED SOLAR FLARE: A new and rapidly growing sunspot, AR2736, announced itself this morning with a C4-class solar flare. The Earth-directed explosion sent minor waves of ionization rippling through Earth's upper atmosphere and caused a shortwave radio "brownout" over parts of Europe and Africa. Moreover, the explosion hurled a coronal mass ejection (CME) into space, which might deliver a glancing blow to Earth's magnetic field later this week. Visit Spaceweather.com for updates.
NEW: Sign up for Space Weather Alerts and get an instant text message when geomagnetic storms begin.
Above: An extreme ultraviolet image of today's solar flare from NASA's Solar Dynamics Observatory