NASA’s Mars Reconnaissance Orbiter has caught sand dunes on the surface of Mars in the act of shifting. Images from the spacecraft show dunes and ripples that have been pushed by wind as much as 3 meters over the course of several years. “Mars either has more gusts of wind than we knew about before, or the winds are capable of transporting more sand,” Nathan Bridges, planetary scientist at the Johns Hopkins University and lead author of a paper in Geology , said in a press release Nov. 17.
The largest storm seen on Saturn in more than 21 years has now been encircling the planet for a record-breaking 200 days. First appearing as a tiny blemish on Dec. 5, 2010, the storm is still going strong today, surpassing the ringed giant's previous longest tempest, which lasted 150 days back in 1903. NASA’s Cassini spacecraft, in orbit around Saturn, has given astronomers a front-seat view of this enormous maelstrom and provided valuable data. From its humble beginnings, the storm has grown to engulf the entire area between Saturn’s 30th and 51st north latitudes. From north to south, the tempest stretches about 9,000 miles — greater than diameter of the Earth — and covers two billion square miles, or eight times the surface area of our planet. Above:
<img class="alignnone size-full wp-image-92761" title="eaglenebherschel" src="http://www.wired.com/images_blogs/wiredscience/2012/01/eaglenebherschel.jpg" alt="" width="660" height="576" /> The European Space Agency’s Herschel space telescope has captured this gorgeous new view of the famed Eagle Nebula. The Eagle Nebula, located 6,500 light-years away in the constellation Serpens, is visible as a fuzzy red spot to backyard astronomers with a modest telescope.
Astronomers weekly announce the discovery of new exoplanets, some similar in size or temperature to our planet –- but Earth-like worlds are not always far away. Though Saturn's largest moon, Titan, is a small, cold world orbiting on the outskirts of the solar system, it actually boasts many familiar features. “Titan is fascinating because it has some surprising properties so similar to Earth,” said planetary scientist Oded Aharonson from the California Institute of Technology. “It has a liquid which erodes channels, an atmosphere, a hydrologic cycle, and many other parallels.”
There’s something about old photographs. The perfect combination of faded light, outdated coloring, and nostalgia seems to make them more beautiful with age. Perhaps that’s why this collection of images from NASA’s Gemini Program is so great.
In the constellation of Aquila (the Eagle), lies a star nearing the end of its life that is surrounded by a starfish-shaped cloud of gas and dust. A striking image of this object, known as IRAS 19024+0044 has been captured by the NASA/ESA Hubble Space Telescope. Protoplanetary nebulae offer glimpses of how stars similar to the Sun end their lives and how they make the transition to white dwarfs surrounded by planetary nebulae. As it ages, a Sun-like star eventually sheds its outer layers into space, creating a beautiful and often intricately shaped cloud of gas and dust around it. At first, still relatively cool, the star is unable to ionise this gas, which shines only by reflected and scattered stellar light. Only when the temperature of the star increases enough to ionise this protoplanetary nebula does the pattern of gas and dust become a fully fledged planetary nebula.
The magnificent reflection nebula NGC 2023 lies nearly 1500 light-years from Earth. It is located within the constellation of Orion (The Hunter), in a prestigious area of the sky close to the well-known Flame and Horsehead Nebulae. The entire structure of NGC 2023 is vast, at four light-years across.
The pearly wisps surrounding the central star IRAS 10082-5647 in this Hubble image certainly draw the eye towards the heavens. The divine-looking cloud is a reflection nebula, made up of gas and dust glowing softly by the reflected light of nearby stars, in this case a young Herbig Ae/Be star. The star, like others of this type, is still a relative youngster, only a few million years old. It has not yet reached the so-called main sequence phase, where it will spend around 80% of its life creating energy by burning hydrogen in its core. Until then the star heats itself by gravitational collapse, as the material in the star falls in on itself, becoming ever denser and creating immense pressure which in turn gives off copious amounts of heat. Stars only spend around 1% of their lives in this pre-main sequence phase.
At the turn of the 19th century, the binary star system Eta Carinae was faint and undistinguished. In the first decades of the century, it became brighter and brighter, until, by April 1843, it was the second brightest star in the sky, outshone only by Sirius (which is almost a thousand times closer to Earth). In the years that followed, it gradually dimmed again and by the 20th century was totally invisible to the naked eye. The star has continued to vary in brightness ever since, and while it is once again visible to the naked eye on a dark night, it has never again come close to its peak of 1843.
Supernova SN 1987A, one of the brightest stellar explosions since the invention of the telescope more than 400 years ago, is no stranger to the NASA/ESA Hubble Space Telescope. The observatory has been on the frontline of studies into this brilliant dying star since its launch in 1990, three years after the supernova exploded on 23 February 1987. This image of Hubble’s old friend, retreived from the telescope’s data archive, may be the best ever of this object, and reminds us of the many mysteries still surrounding it. Dominating this picture are two glowing loops of stellar material and a very bright ring surrounding the dying star at the centre of the frame. Although Hubble has provided important clues on the nature of these structures, their origin is still largely unknown.
Herschel has recently achieved another major milestone in the currently ongoing performance verification phase. Building on the already demonstrated photometric capabilities of the PACS and SPIRE science instruments employed in the 'sneak preview' and 'first-light' observations, for the first time Herschel has now observed in the 'SPIRE/PACS parallel mode'. One outcome is spectacular views in five different far infrared colours of an area near the galactic plane about 60 degrees away from the direction towards the centre of the Galaxy in the constellation of the Southern Cross, considered a suitable region for demonstration and verification purposes, being representative in having a range in structure sizes and temperatures.
Geomagnetic Storm Strength Increases › View larger An aurora on March 8, 2012 shimmering over snow-covered mountains in Faskrudsfjordur, Iceland. Image courtesy of Jónína Óskarsdóttir
Enlarge NASA's Goddard Space Flight Center/DLR/ASU MORE IMAGES A moon-orbiting spacecraft has compiled a nearly complete map of the lunar surface at its highest resolution to date. The moon is our closest celestial neighbor, but our knowledge of its topography is still fuzzy. That's changing quickly, thanks to the camera on board NASA's Lunar Reconnaissance Orbiter (LRO), which is being used to locate potential landing sites and lunar resources.
An American Astronomical Society Meeting Release January 11, 2012: A new Hubble Space Telescope image centers on the 100-million-solar-mass black hole at the hub of the neighboring spiral galaxy M31, or the Andromeda galaxy, one of the few galaxies outside the Milky Way visible to the naked eye and the only other giant galaxy in the Local Group. This is the sharpest visible-light image ever made of the nucleus of an external galaxy. The Hubble image is being presented today at the meeting of the American Astronomical Society in Austin, Texas. See the rest: <p style="text-align:right;color:#A8A8A8"></p>