A large solar eruption early Sunday morning launched tons of ionized atoms toward the Earth, and solar scientists say that wave of charged solar debris could trigger auroral displays across the northern United States this week.

The eruption was rated a C-3, comparatively small, but it launched a large filament of solar material into space.

"This eruption is directed right at us, and is expected to get here early in the day on Aug. 4th," said astronomer Leon Golub, of the Harvard-Smithsonian Center for Astrophysics.

The sun, which has an 11-year cycle of activity, is just beginning to rebound from an unually long and quiet "solar minimum," so eruptions on this scale have not been seen for several years. 

Called coronal mass ejections, the blasts are monitored by spacecraft and solar observatories, including NASA's Solar Dynamics Observatory, launched in February. 

"We got a beautiful view of this eruption," Golub said. "And there might be more beautiful views to come if it triggers aurorae."

When the charged particles strike the Earth's upper atmosphere, they cause the air molecules to glow, often in a variety of colors. Common in far northern latitudes, the aurorae, or "Northern Lights" are rarely seen in  the middle latitudes. But when the solar eruptions are big enough, they can sometimes be seen in Maryland, and even farther south.

Unfortunately, the weather forecast for late Tuesday and early Wednesday morning is not very good. The last aurora easily seen from Maryland was in November 2004.