No sunspots? No problem. Yesterday the blank sun unleashed a solar flare without the usual aid of a sunspot. At 1408 UT on April 26th, Earth-orbiting satellites detected a surge of X-rays registering B3.8 on the Richter scale of solar flares. Shortly thereafter, SOHO coronagraphs photographed a coronal mass ejection (CME) billowing away from the sun:

The expanding cloud could deliver a glancing blow to Earth's magnetic field late on April 28th or 29th. High-latitude sky watchers should be alert for auroras when it arrives.

This strange solar flare came from a patch of sun (N08,E08) where magnetic fields were not intense enough to form a visible sunspot (sunspots are made of magnetism). Nevertheless, magnetic fields were present with sufficient energy and instability to produce a powerful explosion. NASA's twin STEREO spacecraft, observing the sun from widely separated vantage points, recorded a million mph shock wave or "solar tsunami" spreading from the blast site through the sun's atmosphere: LINK.

Not bad for a "blank sun."