It wasn't quite fireworks, but the sun's activity, coming out of a long, deep lull, picked up a bit over the July Fourth weekend. A group of sunspots, which mark intense magnetic activity, appeared in the past few days—a patch larger and more populous than any yet this year, according to data from the Space Weather Prediction Center.

As we reported in April, this year got off to a slow start in terms of sunspots, which typically wax and wane in an 11-year cycle. The minimum of that cycle brought an exceptionally quiet 2008, one of the least active sunspot years of the century.

Solar activity can have significant impacts in Earth's neighborhood, some 93 million miles (150 million kilometers) away. The so-called space weather that the sun stirs up can fry satellites, corrode pipelines and knock out electricity on massive scales.

Joseph Gurman of the NASA Goddard Space Flight Center, U.S. project scientist for the sun-circling Solar and Heliospheric Observatory (SOHO), characterized the current upwelling as "not unusual for this phase of the solar cycle," as the sun's activity begins to awaken. The region, Gurman says, has burbled with low-level flares, but "it hasn't given up anything huge yet."

For an idea of what might happen the next time the sun does kick up something huge, see our August 2008 feature on solar superstorms and the communications infrastructure.

Image of the sun today with sunspot in lower right: SOHO/ESA/NASA