PIX4616489: Martian dunes in Spring - March: Frost - covered dunes in crater - Detail on dunes in a crater located near the north pole of Mars. Clearly, areas covered with carbon dioxide gel appear on this image obtained by the HIRISE camera of the Mars Reconnaissance probe orbiter on January 1, 2010. HIRISE is a 50 cm telescope that observes visible and near infrared Dunes are often found on crater floors. In the winter time at high northern latitudes the terrain is covered by carbon dioxide ice (dry ice). In the spring as this seasonal ice evaporates many unusual features unique to Mars are visible. On the floor of this crater where there are no dunes, the ice forms an uninterrupted layer. On the dunes however, dark streaks form as surface material from below the ice is mobilized and deposited on top of the ice. In some cases this mobile material probably slides down the steep face of the dune, while in other cases it may be literally blown out in a process of gas release similar to removing a cork from a champagne bottle. Image taken on 1 January 2010 by Mars Reconnaissance Orbiter (MRO) spacecraft / Bridgeman Images
PIX4616548: Traces of flow on Mars - Mars: gullies on impact crater wall - Gullies along a wall of an impact crater (Hale crater). These ravines are thought to indicate the presence of liquid water in the Martian basement. Image obtained by the Mars Reconnaissance Orbiter probe on August 3, 2009. Gullies, on Earth, are usually formed through the action of liquid water. Whether gullies form under today's cold dry conditions on Mars is a major question that planetary scientists are trying to answer. The gullies pictured here in Hale crater are great examples of what a typical Martian gully looks like. Wide V - shaped channels running downhill (from top to bottom) where the material that carved the gully flowed. At the bottom of the channel this material empties out onto a fan - shaped mound. Several gullies are visible here and the fans from each gully overlap one other in complicated ways. Image taken on August 3, 2009 by the HIRISE camera on Nasa's Mars Reconnaissance Orbiter / Bridgeman Images
PIX4617475: Nebula NGC 281 in Cassiopee - Nebula NGC 281 in Cassiopeia - NGC 281 is a star-forming region about 10,000 light years away from Earth in the constellation Cassiopee. At the center of this nebula is the cluster of stars IC 1590 whose stars are only a few million years old. Image obtained by combining light through 3 different filters that highlight oxygen, hydrogen, and sulfur. NGC 281 is a busy workshop of star formation. Prominent features include a small open cluster of stars, a diffuse emission nebula, large lanes of obscuring gas and dust, and dense knots of dust and gas in which stars may still be forming. The open cluster of stars IC 1590 visible around the center has formed only in the last few million years. The brightest member of this cluster is actually a multiple - star system shining light that helps ionize the nebula's gas. The lanes of dust visible below the center are likely homes of future star formation. The entire NGC 281 system lies about 10 thousand light years distant. Narrowband composite (Hubble Palette) H - alpha, OIII, SII / Bridgeman Images
TEC4617579: Les Galeries Lafayette, 38-46ae boulevard Haussmann, Paris 9e. The owners Alphonse Kahn and Theophile Bader entrusted the architect Georges Chedanne in 1906 with the construction of a new stone building. And in view of the success of this new concept, Ferdinand Chanut extended the building in 1910. / Bridgeman Images
PIX4617588: Nebula NGC 1788 in Orion - Nebula NGC 1788 in Orion - This nebula is approximately 1500 years old - light in the constellation Orion. A cloud extends, darker, detaches from the nebula; it is an area of intense star formation. Star - forming region located at about 1500 light years away in Orion constellation / Bridgeman Images