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"I want to know why the universe exist, why there is something greater than nothing."
Steven Hawking
Scientist, Space Lover
Why can we see the entire face of this Moon? When the Moon is in a crescent phase, only part of it appears directly illuminated by the Sun. The answer is earthshine, also known as earthlight and the da Vinci glow. The reason is that the rest of the Earth-facing Moon is slightly illuminated by sunlight first reflected from the Earth. Since the Earth appears near full phase from the Moon -- when the Moon appears as a slight crescent from the Earth -- earthshine is then near its brightest. Featured here in combined, consecutively-taken, HDR images taken earlier this month, a rising earthshine Moon was captured passing slowly near the planet Venus, the brightest spot near the image center. Just above Venus is the star Dschubba (catalogued as Delta Scorpii), while the red star on the far left is Antares. The celestial show is visible through scenic cloud decks. In the foreground are the lights from Palazzolo Acreide, a city with ancient historical roots in Sicily, Italy.
What could have created this unusual terrain on Saturn's moon Titan? The robotic Cassini spacecraft now orbiting Saturn swooped once again, earlier this month, past the Solar System's most enigmatic moon and radar imaged a rich but unusual region that appears to be some sort of shoreline. The choppy, light-colored, high regions on the left appears to be have channels cut by a moving fluid, while the smoother dark regions on the right appear to outline bays. Results from the Huygens probe that landed on Titan earlier this year imply that fluids, possibly liquid methane and not water, might only occupy some of these channels and bays intermittently. The radar image shown above spans about 200 kilometers.
Here lie familiar shapes in unfamiliar locations. On the left is an emission nebula cataloged as NGC 7000, famous partly because it resembles our fair planet's continent of North America. The emission region to the right of the North America Nebula is IC 5070, also known for its suggestive outlines as the Pelican Nebula. Separated by a dark cloud of obscuring dust, the two bright nebulae are about 1,500 light-years away. At that distance, the 4 degree wide field of view spans 100 light-years. This spectacular cosmic portrait combines narrow band images to highlight bright ionization fronts with fine details of dark, dusty forms in silhouette. Emission from atomic hydrogen, sulfur, and oxygen is captured in the narrow band data. These nebulae can be seen with binoculars from a dark location. Look northeast of bright star Deneb in the constellation of Cygnus the Swan. No Textbook: Follow a Free Astronomy Course
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