Lunar Eclipses
25.04.2013

The dark, inner shadow of planet Earth is called the umbra. Shaped like a cone extending into space, it has a circular cross section and is most easily seen during a lunar eclipse. But the complete cross section is larger than the Moon's angular size in the stages of an eclipse.

Apollo s Analemma
22.09.2013

Today, the Sun crosses the celestial equator heading south at 20:44 Universal Time. An equinox (equal night), this astronomical event marks the first day of autumn in the northern hemisphere and spring in the south.

Opportunity s Mars Analemma
16.05.2014

Staring up into the martian sky, the Opportunity rover captured an image at 11:02 AM local mean time nearly every 3rd sol, or martian day, for 1 martian year. Of course, the result...

Bright Spots Resolved in Occator Crater on Ceres
16.09.2015

What created these bright spots on Ceres? The spots were first noted as the robotic Dawn spacecraft approached Ceres, the largest object in the asteroid belt, in February, with the expectation that the mystery would soon be solved in higher resolution images. However, even after Dawn arrived at Ceres in March, the riddle remained.

The Tulip and Cygnus X 1
29.07.2021

This tall telescopic field of view looks out along the plane of our Milky Way Galaxy toward the nebula rich constellation Cygnus the Swan. Popularly called the Tulip Nebula, the brightest glowing cloud of interstellar gas and dust above center is also found in the 1959 catalog by astronomer Stewart Sharpless as Sh2-101.

A Beautiful Trifid
5.08.2022

The beautiful Trifid Nebula is a cosmic study in contrasts. Also known as M20, it lies about 5,000 light-years away toward the nebula rich constellation Sagittarius. A star forming region in the plane...

APOD: 2026 July 1 Б The Cotton Candy Clouds of Rho Ophiuchi
1.07.2026

Although they look like cotton candy, you cannot eat these clouds! Taken in Cádiz, Spain, today's image features the Rho Ophiuchi complex, a rich tapestry of young and old astronomical phenomena. This colorful cloud complex is a nearby star-forming region containing hundreds of young stellar objects, including protostars and T Tauri stars.

Gullies on Mars
24.10.2002

The Gullies of Mars would probably not have been sensational enough for the title of a vintage Edgar Rice Burroughs story about the Red Planet. But it would get the attention of planetary scientists today.

The Coldest Brown Dwarf
30.08.2011

This cosmic snapshot composed with image data from NASA's Wide-field Infrared Survey Explorer (WISE) satellite captures a multitude of faint stars and distant galaxies toward the constellation Lyra at wavelengths longer than visible light. But the object circled at the center is not quite a star.

Through a Sun Tunnel
22.12.2011

Today the Sun stands still at 05:30 UT. Halting its steady march toward southern declinations and begining its annual journey north, the event is known as a solstice. In the northern hemisphere December's solstice marks the astronomical start of winter.