SUNSET: 
Explore the Night with Bob King
Uncovering Secrets of Earth's Shadow
The daily rising and setting of Earth's shadow is a beautiful sight anyone on the planet can view. It's also an opportunity to witness the rapid changes that accompany sunset or sunrise, but at the opposite end of the sky.
A Sunrise Annular Solar Eclipse
Even if you're not in the path of annularity during the June 10th solar eclipse, get ready for a sunrise spectacle.
Planets and Comets Can't Hide from SOHO's Eye
With the help of the Solar Heliospheric Observatory you can not only keep track of the planets in the daytime sky but maybe even discover a comet.
Nights of Noctilucent Clouds
Noctilucent clouds shimmer high in the sky during summer twilight at northerly latitudes.
Volcanoes Turn Twilights Purple
A rash of unusually colorful sunsets follows in the wake of two major volcanic eruptions.
Explore the Night with Bob King
How to See Sirius in the Daytime
Spotting Sirius in broad daylight may be easier than you think! Here's how to do it.
Quest for the Green Flash
If you like sunrises and sunsets, look for the green flash, a phenomenon that happens more often that you think.
Earth's Shadow Creeps Up on Us Every Night
The next time you're out watching a sunset, turn around and relish the mighty shadow of Earth looming just behind your back.
Catch the Green Flash!
It sounds like a comic-book superhero, but this brief spectacle marks the end of daylight with a burst of color.
Reanimating the 1882 Transit of Venus
Travel 130 years back in time to watch Venus transit the Sun in 1882, thanks to the discovery of 147 forgotten photographs taken by David Peck Todd from Mount Hamilton in California.
The Transit of Venus: Tales from the 18th and 19th Centuries
Observers and administrators gather at the US Naval Observatory in Washington, DC, in preparation for the American expeditions to the 1874 transit of Venus.Courtesy US Naval Observatory Library. A magnificent rendezvous between the planet of love and the bright orb of the Sun. One of the most celebrated phenomena in…