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Sidereal time: What is it?
Sidereal time measures the rotation of our planet relative to the stars. It allows astronomers to keep time without worrying about the motion of Earth around the sun.
June 10, 2012
Venus transit on June 5-6: Everything you need to know:
The Venus transit appeared as a small dark dot crossing sun's face for last time this century on June 5-6, 2012. Last transit of Venus in our lifetimes!
June 5, 2012
Three planets – Mars, Saturn, Venus – at nightfall throughout May 2012
Three planets light up the sky as soon as darkness falls on these May 2012 nights. This post tells you how to spot them.
May 1, 2012
Why was Venus so bright in late April and early May 2012?
Venus is at its brightest in late April and early May 2012. It's so bright it might surprise you. Some will report it as a UFO. But why so bright?
April 29, 2012
2012 annular eclipse of the sun – China to Texas – in May
Everything you need to know - whether you're in Earth's eastern or western hemisphere - about the 2012 annular eclipse of the sun.
March 5, 2012
Venus-Jupiter conjunction of March 2012
See the Venus-Jupiter conjunction in March 2012. They're spectacular this month - and near the moon by the month's end. Charts here.
March 4, 2012
Finding Comet Garradd in December 2011
Search for Comet Garradd before dawn and in the eastern sky, starting around the December solstice. Look for it with binoculars.
December 23, 2011
Moon facts at your fingertips
See below for a list of links to fun and useful facts about Earth's companion world. Learn these moon facts and impress your friends.
December 5, 2011
How to see Mars in August 2011
Mars will not look as big as the moon on August 27, 2011. But, in August 2011, you can see Mars as respectably bright ruddy star, in the eastern predawn sky
August 27, 2011
Mercury waltzes with bright planets at dawn May 2011
As Mercury reemerges as a morning object in May 2011, the solar system’s innermost planet will join up with the planets Jupiter, Venus and Mars in the eastern sky at dawn.
May 3, 2011
