We are now officially in spring, since the vernal equinox was last Friday.
Because the Earth moves around the sun completely once a year, the sun appears to move slowly across the sky from day to day. When the sun crosses directly over the equator from the southern to the northern part of the sky, winter officially gives way to spring. This is the vernal or spring equinox. It happens around March 21 every year.
"Equinox" means "equal night" — the hours of day and night are equal. In theory they are equal at the vernal equinox in March and the autumnal equinox around Sept. 21, but at these times there is actually somewhat more daylight than night. The atmosphere acts as a giant lens and bends the sun's light up above the horizon. We see the sun's light a few minutes before sunrise and a few minutes after sunset. However, on the vernal and autumnal equinoxes, the sun rises due east and sets due west.
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Today is a new moon. That means the moon won't be visible today but will be a beautiful thin crescent in the evening sky this weekend. The moon will be a waxing (increasing) crescent until it reaches first quarter next Thursday.
Once a waxing crescent moon reaches the configuration of a semicircle, it becomes a first-quarter moon. As the moon's shape grows beyond a semicircle, it becomes a waxing gibbous moon until it reaches full moon. Then it begins to shrink down as a waning (shrinking) gibbous moon until it again reaches a semicircle configuration as a last-quarter moon. Next it becomes a waning crescent until it disappears as a new moon to start the cycle all over again. The time from one new moon to another new moon is about 29.5 days, a lunar month.