An active sunspot is amping up the sun's activity, and has already unleashed two strong solar flares that triggered weekend geomagnetic storms on Earth, NASA officials say. The M-class solar flares set off two coronal mass ejections (CMEs) that erupted from the sun on last Wednesday and Thursday (June 13 and June 14). The first flare peaked Wednesday at 9:17 a.m. EDT (1317 GMT), and…