The winter solstice is the shortest day of the year, respectively, in the sense that the length of time elapsed between sunrise and sunset on this day is a minimum for the year. Of course, daylight saving time means that the first Sunday in April has 23 hours and the last Sunday in October has 25 hours, but these human meddlings with the calendar and do not correspond to the actual number of daylight hours.
http://scienceworld.wolfram.com/astronomy/WinterSolstice.html
Not usually as spectacular as the Perseids (August) or Geminids (December) showers, but this year the two Big Showers happen very near the full moon. However, this Quadrantids shower will take place in the deep dark of the new moon — so this may in fact be the best shower in 2011.
From Wikipedia: “The peak intensity is exceedingly sharp: the meteor rates exceed one-half of their highest value for only about 8 hours (compared to two days for the August Perseids). This means that the stream of particles that produces this shower is narrow – and apparently deriving from and within the last 500-years from some orbiting body.”
The eclipse will be visible over most of Europe, the Arabian peninsula, North Africa and Western Asia. See http://tinyurl.com/284fkyp
The date (near March 21 in the northern hemisphere) when night and day are nearly the same length and Sun crosses the celestial equator (i.e., declination 0) moving northward. In the southern hemisphere, the vernal equinox corresponds to the center of the Sun crossing the celestial equator moving southward and occurs on the date of the northern autumnal equinox. The vernal equinox marks the first day of the season of spring.
http://scienceworld.wolfram.com/astronomy/VernalEquinox.html