Neither rain, nor snow, nor dark of night can keep a space-based spacecraft from watching the Sun. In fact, from its vantage point 1.5 million kilometers sunward of planet Earth, NASA's SOlar Heliospheric Observatory (SOHO) can always monitor the Sun's outer atmosphere, or corona.

Sometimes falling ice crystals make the atmosphere into a giant lens causing arcs and halos to appear around the Sun or Moon. This past Saturday night was just such a time near Madrid, Spain, where a winter sky displayed not only a bright Moon but as many as four rare lunar halos.

Like cosmic snowballs, fluffy comet-like objects the size of houses and composed mostly of water-ice, may be pummeling planet Earth 5 to 30 times a minute. This controversial theory was originally proposed in 1986 by Dr. Louis Frank (U. Iowa) based on data from NASA's Dynamics Explorer 1.