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| Sunday, 26 June 2005 |
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Junior Observer |  |
| News Business Features Editorial
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Hubble celebrates with new images
The Hubble was placed into Earth-orbit on April 25, 1990. For the first time, a large telescope that sees invisible light began orbiting above Earth's distorting atmosphere, which blurs starlight and makes images appear fuzzy. Astronomers anticipated great discoveries from Hubble. The telescope has delivered as promised and continues serving up new discoveries.
The new image of the well-known spiral galaxy M51 (known as the Whirlpool Galaxy), showcases a spiral galaxy's classic features, from its curving arms, where newborn stars reside, to its yellowish central core, a home for older stars. A feature of considerable added interest is the companion galaxy located at the end of one of the spiral arms.
The pictures are among the largest and sharpest views taken by Hubble. The images, taken by Hubble's Advanced Camera for Surveys, are 20 times larger than a photograph taken by a typical digital camera. The new images are so sharp that they could be enlarged to billboard size and still retain the stunning details. Courtesy - NASA ######### Ice volcanoes on Saturn's moon? Thanks to the latest technology, we are able to get information about things that take place hundreds and thousands of kilometres away. The latest information technology has gifted us is about the planet Saturn. A team of European and US scientists, using Cassini-Huygens data, have found that Saturn's smoggy moon Titan may have volcanoes that release methane in the atmosphere. This information will help scientists to revise the theories that the presence of methane in Titan's atmosphere is mainly due to the presence of a methane-rich hydrocarbon ocean. Infrared images taken by the Visual and Infrared Mapping Spectrometer (VIMS) on board the Cassini orbiter, show a bright, 30-kilometre-wide structure. This structure, imaged during the first Titan fly-by on October 26, 2004 from a distance of 1,200 kilometres, could be interpreted as a volcanic dome formed by upwelling plumes of icy material that rose to the planet's surface. While melting, the icy material contaminated by hydrocarbons would release methane gas. The eruptions of such an ice-volcano, or 'cryo-volcano', would be caused by the heat generated during tidal movements of material inside Titan. Internal tides at Titan are expected as this moon strongly varies its distance from Saturn while it runs along its highly elliptical orbit around the mother planet. The images of the observed area also show that liquid is not visible on the surface.According to Dr. Christophe Sotin, from the University of Nantes (France) and lead author of the results, before Cassini-Huygens, the most widely accepted explanation for the presence of methane in Titan's atmosphere was the presence of a methane-rich hydrocarbon ocean. Scientists have already considered, and ruled out, other interpretations for the 30-kilometre circular structure. In principle, it could be a cloud, but images taken at different times show that the structure does not vary its shape. A second interpretation would suggest that the structure is an accumulation of solid particles transported by gas or liquid, as it happens for sand dunes on Earth.However, a circular shape does not really match with this process, and its possible that wind patterns do not match with the expected wind directions on Titan. Radar observations of the same regions to be made later by Cassini will certainly help to confirm these findings. - Compiled by Chamitha Kuruppu Source - ESA |
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| Politics | Produced by Lake House |
The NASA's Hubble Space Telescope has helped astronomers to discover
many mysteries for 15 long years. To celebrate Hubble's 15th anniversary
this year, new breathtaking images are being released about a majestic
spiral galaxy teeming with newborn stars and an eerie-looking spire of gas
and dust. 
During its 15 years of viewing the universe, the telescope has taken
more than 700,000 snapshots of celestial objects such as galaxies, dying
stars, and giant gas clouds, the birthplace of stars.The versatile
telescope continues to deliver exciting new science, and helps to prove
the existence of dark energy, tracing enigmatic gamma-ray bursts to
distant galaxies, and sampling the atmospheres of far-flung planets. 
The new photograph of the Eagle Nebula shows a tall, dense tower of gas
that is being sculptured by ultraviolet light from a group of massive, hot
stars. 
