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Explanation: There's something behind these clouds. Those faint graceful arcs, upon inspection, are actually far, far in the distance. They are the Earth's Moon and the planet Venus. Both the Moon and Venus are bright enough to be seen during the day, and both are quite capable of showing a crescent phase. To see Venus, which appears quite small, in a crescent phase requires binoculars or a telescope. In the above dramatic daytime image taken from Budapest, Hungary, the Moon and Venus shared a similar crescent phase a few minutes before the Moon eclipsed the larger but more distant world. About an hour later, Venus reappeared.

Explanation: What created this huge space bubble? Blown by the wind from a star, this tantalizing, ghostly apparition is cataloged as NGC 7635, but known simply as The Bubble Nebula. Astronomer Eric Mouquet's striking view utilizes a long exposure with hydrogen alpha light to reveal the intricate details of this cosmic bubble and its environment. Although it looks delicate, the 10 light-year diameter bubble offers evidence of violent processes at work. Seen here above and right of the Bubble's center is a bright hot star embedded in reflecting dust. A fierce stellar wind and intense radiation from the star, which likely has a mass 10 to 20 times that of the Sun, has blasted out the structure of glowing gas against denser material in a surrounding molecular cloud. The intriguing Bubble Nebula lies a mere 11,000 light-years away toward the boastful constellation Cassiopeia.

Credit & Copyright: Eric Mouquet

from: http://antwrp.gsfc.nasa.gov/apod/

Explanation: This crowded star field towards the center of our Milky Way Galaxy turns out to be a great place to search for planets beyond our solar system. In fact, repeatedly imaging about 180,000 stars in the field over a one week period, the Hubble Space Telescope enabled astronomers to conduct the Sagittarius Window Eclipsing Extrasolar Planet Search (SWEEPS). Their search looked for brief, periodic dips in brightness caused as a large planet eclipses or transits its parent star. Since chances of seeing such an eclipse are slim, it was a definite advantage to examine as many stars as possible. In the end, SWEEPS astronomers found 16 candidate stars (green circles identify 11 in this cropped picture) that are likely closely orbited by large Jupiter-sized planets with periods of a few days or less. Large planets orbiting so close to their stars are termed hot Jupiters. Kepler, a future NASA mission, is intended to extend the transit technique to search for Earth-sized planets.