Astronomy Picture Of the Day (APOD)Crescent Rhea Occults Crescent Saturn
Soft hues, partially lit orbs, a thin trace of the ring, and slight shadows highlight this understated view of the majestic surroundings of the giant planet Saturn. Looking nearly back toward the Sun, the robot Cassini spacecraft now orbiting Saturn captured crescent phases of Saturn and its moon Rhea in color a few months ago.
Dark Sun Sizzling
Is this our Sun? Yes. Even on a normal day, our Sun is sizzling ball of seething hot gas. Unpredictably, regions of strong and tangled magnetic fields arise, causing sunspots and bright active regions. The Sun's surface bubbles as hot hydrogen gas streams along looping magnetic fields.
The Eskimo Nebula from Hubble
In 1787, astronomer William Herschel discovered the Eskimo Nebula. From the ground, NGC 2392 resembles a person's head surrounded by a parka hood. In 2000, the Hubble Space Telescope imaged the Eskimo Nebula. From space, the nebula displays gas clouds so complex they are not fully understood.
Discovery in Motion
On July 4th, the space shuttle orbiter Discovery rocketed into space on mission STS-121. Now docked with the International Space Station, Discovery orbits planet Earth at about 27 thousand kilometers per hour.
Bright Galaxy M81
Big and beautiful spiral galaxy M81 lies in the northern constellation Ursa Major. One of the brightest galaxies in planet Earth's sky, M81 is also home to the second brightest supernova seen in modern times.
NGC 6888: A Tricolor Starfield
NGC 6888, also known as the Crescent Nebula, is a cosmic bubble about 25 light-years across, blown by winds from its central, bright, massive star. Near the center of this intriguing widefield view of interstellar gas clouds and rich star fields of the constellation Cygnus, NGC 6888 is about 5,000 light-years away.
Spiral Galaxy NGC 2403 from Subaru
Sprawling spiral arms dotted with bright red emission nebulas highlight this new and detailed image of nearby spiral galaxy NGC 2403. Also visible in the photogenic spiral galaxy are blue open clusters, dark dust lanes, and a bright but relatively small central nucleus.
Elliptical Galaxy Centaurus A from CFHT
Why is peculiar galaxy Centaurus A so dusty? Dramatic dust lanes that run across the galaxy's center mark Cen A. These dust lanes are so thick they almost completely obscure the galaxy's center in visible light.
The View toward Husband Hill on Mars
This Martian vista is only part of one of the greatest panoramic views of Mars that has ever attempted. The expansive mosaic is helping to keep the robotic Spirit rover busy over the energy draining winter in the southern hemisphere of Mars.
Tornado and Rainbow Over Kansas
The scene might have been considered serene if it weren't for the tornado. Last June in Kansas, storm chaser Eric Nguyen photographed this budding twister in a different light -- the light of a rainbow. Pictured above, a white tornado cloud descends from a dark storm cloud.