May 21, 2006, 11:58 PM CT

Three New Planets Discovered!

Three more planets! Yes, all credits go to the Chilean telescope. It has discovered a unique planetary system that shelters three planets in it. The planets are found to be similar to Neptune. It is also found to be orbiting a star, which as per the European Southern Observatory, is a little more massive than our sun.

The observatory in a news release said,.

"The planet closest to the star is probably rocky and the farthest is the first exoplanet of that mass that is in the habitable zone of its star, meaning, where water could be found in liquid form".

Christophe Lovis, astronomer with Switzerland's Observatory of Geneva and the lead author of an article about the find said,.

"It's the first discovery of a planetary system made up of various planets of a Neptune-type mass. ".

The planetary system is discovered 41 light years away in the Puppis constellation. This finding is the result of observing the star for more than two years. Scientist teams from the Observatory of Geneva and the University of Bern Physics Institute - both in Switzerland, did this study. Nature magazine will be publishing this finding on Thursday.........

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May 21, 2006, 9:45 AM CT

Cluster Flies Through Earth's Electrical Switch

ESA's Cluster satellites have flown through regions of the Earth's magnetic field that accelerate electrons to approximately one hundredth the speed of light. The observations present Cluster researchers with their first detection of these events and give them a look at the details of a universal process known as magnetic reconnection.

On 25 January 2005, the four Cluster spacecraft found themselves in the right place at the right time: a region of space known as an electron diffusion region. It is a boundary just a few kilometres thick that occurs at an altitude of approximately 60 000 kilometres above the Earth's surface. It marks the frontier between the Earth's magnetic field and that of the Sun. The Sun's magnetic field is carried to the Earth by a wind of electrically charged particles, known as the solar wind.

An electron diffusion region is like an electrical switch. When it is flipped, it uses energy stored in the Sun's and Earth's magnetic fields to heat the electrically charged particles in its vicinity to large speeds. In this way, it initiates a process that can result in the creation of the aurora on Earth, where fast-moving charged particles collide with atmospheric atoms and make them glow.

There is also a more sinister side to the electron diffusion regions. The accelerated particles can damage satellites by colliding with them and causing electrical charges to build up. These short circuit and destroy sensitive equipment.........

Posted by: Brooke      Permalink         Source

May 21, 2006, 9:40 AM CT

Disintegration Of A Comet

The continuing disintegration of Comet 73P/Schwassmann-Wachmann 3 has allowed ESA researchers to see into the interior of the comet. Using a revolutionary camera attached to the ESA Optical Ground Station on Tenerife, they have followed the detailed twists and turns of various comet fragments.

The superconducting camera, SCAM, is an ultra fast photon counting camera, developed by ESA. It is cooled to just 300 thousandths of a degree above absolute zero. This enables its sensitive electronic detectors, known as superconducting tunnel detectors, to register almost every single photon of light that falls into it. As such, it is the perfect instrument with which to detect fast and faint changes in the fragments of the comet.

Comet 73P/Schwassmann-Wachmann 3 is a short-period comet that approaches the Sun every 5.4 years. Two apparitions ago, in 1996, the comet nucleus split into five pieces (Fragments A, B, C, D, E) of which 3 (B, C, E) were still visible at its 2001 return.

When it approached the Sun again this year, seven fragments were initially observed, indicating that the comet was breaking apart again. Indeed, as astronomers watched, further fragments broke off. Fragment B alone produced at least seven new pieces. At present, about 40 fragments are visible, most of which are likely to be very small and with irregular and short-lived activity.........

Posted by: Brooke      Permalink         Source

May 18, 2006, 9:33 PM CT

Aorounga Impact Crater, Chad

The impact of an asteroid or comet several hundred million years ago left scars in the landscape that are still visible in this spaceborne radar image of an area in the Sahara Desert of northern Chad. The concentric ring structure is the Aorounga impact crater, with a diameter of about 17 kilometers (10.5 miles). The original crater was buried by sediments, which were then partially eroded to reveal the current ring-like appearance. The dark streaks are deposits of windblown sand that migrate along valleys cut by thousands of years of wind erosion.

The dark band in the upper right of the image is a portion of a proposed second crater. Researchers are using radar images to investigate the possibility that Aorounga is one of a string of impact craters formed by multiple impacts. Radar imaging is a valuable tool for the study of desert regions because the radar waves can penetrate thin layers of dry sand to reveal details of geologic structure that are invisible to other sensors. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) on April 18 and 19, 1994, onboard the space shuttle Endeavour. The area shown is 22 kilometers by 28 kilometers (14 miles by 17 miles) and is centered at 19.1 degrees north latitude, 19.3 degrees east longitude. North is toward the upper right. The colors are assigned to different radar frequencies and polarizations as follows: red is L-band, horizontally transmitted and received; green is C-band, horizontally transmitted and received; and blue is C-band, horizontally transmitted, vertically received. SIR-C/X-SAR, a joint mission of the German, Italian and United States space agencies, is part of NASA's Mission to Planet Earth program.........

Posted by: Brooke      Permalink         Source

May 18, 2006, 9:26 PM CT

Cracking Comet Streaks Across the Sky

Researchers using NASA's Swift satellite have detected X-rays from a comet that is now passing the Earth and rapidly disintegrating on what could be its final orbit around the sun.

Swift's observations provide a rare opportunity to investigate several ongoing mysteries about comets and our solar system, and hundreds of researchers have tuned in to the event.

The comet, called 73P/Schwassmann-Wachmann 3, is visible with even a small, backyard telescope. Peak brightness is expected next week, when it comes within 7.3 million miles of Earth, or about 30 times the distance to the Moon. There is no threat to Earth, however.

This is the brightest comet ever detected in X-rays. The comet is so close that astronomers are hoping to determine not only the composition of the comet but also of the solar wind. Researchers believe that atomic particles that comprise the solar wind interact with comet material to produce X-rays, a theory that Swift might prove true.

Three world-class X-ray observatories now in orbit---NASA's Chandra X-ray Observatory, the European-led XMM-Newton, and the Japanese-led Suzaku---will observe the comet in the coming weeks. Like a scout, Swift has provided information to these larger facilities about what to look for. This type of observation can only take place in the X-ray waveband.........

Posted by: Brooke      Permalink         Source

May 18, 2006, 9:22 PM CT

How Big is Big?

A team of scientists, which includes a Penn State astronomer, is announcing the construction of a new map of the sky containing more than 600,000 galaxies that covers distances of well over a billion light-years. "The map was created with data from several years of observations by the Sloan Digital Sky Survey," said Penn State Professor of Astronomy and Astrophysics Donald Schneider, a coauthor of the investigation. "The extremely large luminosities of the galaxies allow us to detect them at great distances, and the large-scale distribution of the sources carries information about the conditions present in the very early universe." Schneider is the Chairman of the Sloan Digital Sky Survey (SDSS) Quasar Science Group and the SDSS Scientific Publications Coordinator.

Since the 1970s, astronomers have discovered structures in the three-dimensional distribution of galaxies on ever larger scales, up to hundreds of millions of light years. Scientists from the Sloan Digital Sky Survey (SDSS-II) announced the first measurements of galactic structures more than a billion light years across.

The three-dimensional map of more than 600,000 galaxies covers over one-tenth of the sky. "The volume probed here is the same as a cube 5.3 billion light years on a side," said principal author Nikhil Padmanabhan of Princeton University. "It reaches one-third of the way to the edge of the observable Universe, and we measure structures that extend over a significant fraction of that distance".........

Posted by: Brooke      Permalink         Source

May 17, 2006, 11:46 PM CT

Photosynthetic Trends In Northern Circumpolar High Latitudes

Using time series analyses of a 22-year record of satellite observations across the northern circumpolar high latitudes, researchers at the Woods Hole Research Center are assessing trends in vegetation photosynthetic activity. The results indicate that tundra areas consistently and predominantly show greening trends while forested areas show browning, indicating that the boreal forest biome might be responding to climate change in previously unexpected ways. This research is highlighted in the current issue of Earth Interactions.

As per Andrew Bunn, lead author of the paper and a post-doctoral fellow at the Center, "This research suggests that the high latitudes might not be responding to climate change as previously thought. If the ability of boreal forests to capture and store carbon in a warmer world is not as great as we've previously supposed, then we will have to think differently about how the planet will respond to continuing emissions of carbon dioxide."

All land surfaces above 50 degree N, excluding the glaciers of Greenland, were included in this study. Growing seasons were defined as May to August though early and late growing season periods were also considered. Three primary data sets derived from polar-orbiting satellites were used.

Overall, tundra areas show marked greening over the entire growing season. These patterns were consistent with relatively simple climate response seen in related work in North America, where areas responded to summer maximum temperatures while the response of forest vegetation was more complex. Boreal forests patterns indicate significant greening in May and June, with gains offset by substantive browning in July and August.........

Posted by: Jessica      Permalink

May 16, 2006, 11:56 PM CT

Looking At Hurricane Cloud Tops For Windy Clues

Researchers at NASA are finding that with hurricanes, they can look at the cloud tops for clues about the behavior of winds below the hurricane on the Earth's surface.

By looking at how high up the rain is forming within clouds, researchers can estimate whether the hurricane's surface winds will strengthen or weaken. They have found that if rain is falling from clouds that extend up to 9 miles high, and that rain continues for at least one out of three hours, a hurricane's surface winds are likely going to get stronger.

To see into the cloud tops, NASA researchers developed a precise mathematical method or a technique with the very precise rain measurements from the radar onboard the Tropical Rainfall Measuring Mission (TRMM) satellite. Once this technique was developed it was applied to data collected by National Weather Service radars on the ground.

"Thanks to the precise measurements from TRMM, we've found a new way to use data that's collected all the time by weather radars on the ground," said Owen Kelley, scientist at NASA's Goddard Space Flight Center, Greenbelt, Md.

Kelley and researchers John Stout of NASA Goddard and Jeff Halverson of the University of Maryland Baltimore County calculated statistics that suggest forecasters could use TRMM's rain-height observations to improve existing observations and computer model forecasts of hurricane winds. "The trick is to keep an eye on the height of rain that radars see when a hurricane approaches within 200 miles of the coast," Kelley said.........

Posted by: Tyler      Permalink         Source

May 15, 2006, 11:57 PM CT

A Ruler to Measure the Universe

A team of astronomers led by Nikhil Padmanabhan and David Schlegel has published the largest three-dimensional map of the universe ever constructed, a wedge-shaped slice of the cosmos that spans a tenth of the northern sky, encompasses 600,000 uniquely luminous red galaxies, and extends 5.6 billion light-years deep into space, equivalent to 40 percent of the way back in time to the Big Bang.

Schlegel is a Divisional Fellow in the Physics Division of Lawrence Berkeley National Laboratory, and Padmanabhan will join the Lab's Physics Division as a Chamberlain Fellow and Hubble Fellow in September; presently he is at Princeton University. They and their coauthors are members of the Sloan Digital Sky Survey (SDSS), and have previously produced smaller 3-D maps by using the SDSS telescope in New Mexico to painstakingly collect the spectra of individual galaxies and calculate their distances by measuring their redshifts.

"What's new about this map is that it's the largest ever," says Padmanabhan, "and it doesn't depend on individual spectra."

The principal motive for creating large-scale 3-D maps is to understand how matter is distributed in the universe, says Padmanabhan. "The brightest galaxies are like lighthouses - where the light is, is where the matter is."........

Posted by: Brooke      Permalink         Source

May 14, 2006, 11:24 AM CT

Trail of Comet Crumbs

NASA's Spitzer Space Telescope has snapped a picture of the bits and pieces making up Comet 73P/Schwassman-Wachmann 3, which is continuing to break apart on its periodic journey around the sun. The new infrared view shows several chunks of the comet riding along its own dusty trail of crumbs.

"Spitzer has revealed a trail of meteor-sized debris filling the comet's orbit," said Dr. William T. Reach of NASA's Spitzer Science Center at the California Institute of Technology, Pasadena. Reach and his team recently observed the comet using Spitzer.

Comet 73P/Schwassman-Wachmann 3 consists of a collection of fragments that file along like ducks in a row around the sun every 5.4 years. This year, the bunch will pass by Earth beginning on May 12 before swinging by the sun on June 6. The fragments won't get too close to Earth, about 7.3 million miles, or 30 times the distance between Earth and the moon, but they should be visible through binoculars in the countryside night skies.

The icy comet began falling apart in 1995 during one of its tropical trips to the sun. Astronomers think that its crusty outer layer cracked due to the heat, allowing fresh ice to evaporate and split the comet apart.

During the past six weeks, amateur and professional astronomers have been watching the comet fall apart before their telescopes' eyes. Spitzer viewed the broken comet from its quiet perch up in space May 4 to May 6, covering a portion of the sky that allowed it to spot 45 of the 58 known fragments.........

Posted by: Brooke      Permalink         Source

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