Comet LINEAR Breaks Up
31.07.2000

Unexpectedly, Comet LINEAR is breaking up. In retrospect, clues of its demise have been surfacing all month as the new comet has been approaching the Sun and brightening with dramatic flares. Above, the Hubble Space Telescope captured Comet C/1999 S4 LINEAR early this month blowing off a large piece of its crust.

The Solar Spectrum
29.06.2003

It is still not known why the Sun's light is missing some colors. Shown above are all the visible colors of the Sun, produced by passing the Sun's light through a prism-like device.

El Nino Earth
12.11.1997

El Niño is a temporary global climate change resulting from unusually warm water in the central Pacific Ocean. El Niño can cause unusual or severe weather for some locations over the next few months.

Apollo 17: Last on the Moon
17.12.2005

In December of 1972, Apollo 17 astronauts Eugene Cernan and Harrison Schmitt spent about 75 hours on the Moon, in the Taurus-Littrow valley, while colleague Ronald Evans orbited overhead. Near the beginning of their...

Charles P. Conrad Jr 1930 1999
15.07.1999

Known for his sense of humor and infectious grin, Charles P. "Pete" Conrad, as commander of the Apollo 12 mission, was the third person to walk on the moon. Not a tall man, Conrad stepped down onto the lunar surface in November of 1969 and gleefully commented, "Whoopie!

A Twisted Solar Eruptive Prominence
1.06.2008

Ten Earths could easily fit in the "claw" of this seemingly solar monster. The monster, though, visible on the lower left, is a huge eruptive prominence seen moving out from our Sun. The above dramatic image taken early in the year 2000 by the Sun-orbiting SOHO satellite.

A Solar Prominence from SOHO
31.05.2009

How can gas float above the Sun? Twisted magnetic fields arching from the solar surface can trap ionized gas, suspending it in huge looping structures. These majestic plasma arches are seen as prominences above the solar limb.

A Double Eclipse of the Sun
21.03.2015

Can the Sun be eclipsed twice at the same time? Last Friday was noteworthy because part of the Earth was treated to a rare total eclipse of the Sun. But also on Friday, from...

The Fractured North Pole of Saturns Enceladus
21.10.2015

The north pole of Saturn's moon Enceladus is unexpectedly fascinating and complex. Previous to the latest flyby of the robotic Cassini spacecraft, the northern region was known mostly for its unusually high abundance of craters.

A Symphony in Northern Winter Skies
22.03.2019

Despite the cold, a chance to view the shimmering northern lights coaxed this skygazer onto the frozen surface of Lake Superior on the west coast of the Keweenaw Peninusla and offered this nocturnal crescendo as a reward.