Tycho and Copernicus: Lunar Ray Craters
5.03.2005

Dazzling in binoculars or a small telescope, the Moon is pocked with impact craters. During partial lunar phases, the craters along the terminator are cast in dramatic relief by strong shadows. But when the Moon is full some craters seem to sprout systems of bright radial lines or rays.

Diamond Rings and Baily s Beads
27.03.2015

Near the March 20 equinox the cold clear sky over Longyearbyen, Norway, planet Earth held an engaging sight, a total eclipse of the Sun. The New Moon's silhouette at stages just before...

Venus and Jupiter are Far
3.07.2015

On June 30 Venus and Jupiter were actually far apart, but both appeared close in western skies at dusk. Near the culmination of this year's gorgeous conjunction, the two bright evening planets...

The ISS and a Colorful Moon
31.07.2015

Tonight's Full Moon, the second Full Moon in July, could be called a blue moon according to modern folklore. But this sharp and detailed mosaic, recorded with telescope and digital camera just before July's first Full Moon, actually does show a colorful lunar surface.

Madagascar Totality
26.07.2001

When the Moon's shadow reached out and touched Earth's southern hemisphere on 2001 June 21, the first total solar eclipse of the 21st century began. Starting in the Atlantic, the dark, central...

Changes in Angular Mars
14.07.2008

Does Mars always appear the same? No. As both Earth and Mars orbit the Sun, the apparent angular size of Mars changes as viewed from the Earth. Pictured above from Enschede, Holland, Mars was captured in 2007 and 2008 with 30 separate images, all taken with the same magnification.

Diamond Ring and Shadow Bands
24.07.2010

As the total phase of July 11's solar eclipse came to an end, sunlight streaming past the edge of the Moon's silhouette created the fleeting appearance of a glistening diamond ring in the sky.

MyCn18: An Hourglass Planetary Nebula
7.08.2011

The sands of time are running out for the central star of this hourglass-shaped planetary nebula. With its nuclear fuel exhausted, this brief, spectacular, closing phase of a Sun-like star's life occurs as its outer layers are ejected - its core becoming a cooling, fading white dwarf.

Full Moonrise
5.05.2012

Rising as the Sun sets, tonight's Full Moon could be hard to miss. Remarkably, its exact full phase (May 6 03:36 UT) will occur less than two minutes after it reaches perigee, the closest point to Earth in the Moon's orbit, making it the largest Full Moon of 2012.

The Last Days of Venus as the Evening Star
6.01.2022

That's not a young crescent Moon posing behind cathedral towers after sunset. It's Venus in a crescent phase. About 40 million kilometers away and about 2 percent illuminated by sunlight...