Satellite News

Satellites are used for a large number of purposes. Common types include military (spy) and civilian Earth observation satellites, communication satellites, navigation satellites, weather satellites, and research satellites.

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NASA Probe Sees Solar Wind Decline

The 33-year odyssey of NASA's Voyager 1 spacecraft has reached a distant point at the edge of our solar system where there is no outward motion of solar wind. Now hurtling toward interstellar space some 17.4 billion...

Super-Earth Atmosphere

A team of astronomers, including two NASA Sagan Fellows, has made the first characterizations of a super-Earth's atmosphere, by using a ground-based telescope...

Kepler Discovers

NASA's Kepler spacecraft has discovered the first confirmed planetary system with more than one planet crossing in front of, or transiting, the same star...

Pulverized Planet

Tight double-star systems might not be the best places for life to spring up, according to a new study using data from NASA's Spitzer Space Telescope....

Dark Asteroids

NASA is set to launch a sensitive new infrared telescope to seek out sneaky things in the night sky -- among them, dark asteroids that could pose a threat to Earth....

Archive for November 2009

NASA is now joining in to combat the 2012 nonsense. Don Yeomans, manager of NASA's Near Earth Object office has produced a video and written an article, providing the scientific realities surrounding the celestial happenings of 2012. Yeomans has done a wonderful job explaining everything that is and isn't going to happen in 2012, and we're happy to add his work to our collection.

Nibiru, a purported large object headed toward Earth, simply put – does not exist. There is no credible evidence – telescopic or otherwise – for this object's existence. There is also no evidence of any kind for its gravitational affects upon bodies in our solar system.

The Mayan calendar does not end in December 2012. Just as the calendar you have on your kitchen wall does not cease to exist after December 31, the Mayan calendar does not cease to exist on December 21, 2012. This date is the end of the Mayan long-count period, but then – just as your calendar begins again on January 1 – another long-count period begins for the Mayan calendar.

There are no credible predictions for worrisome astronomical events in 2012. The activity of the sun is cyclical with a period of roughly 11 years and the time of the next solar maximum is predicted to occur in the period 2010 – 2012. However, the Earth routinely experiences these periods of increased solar activity – for eons – without worrisome effects.

The Earth’s magnetic field, which deflects charged particles from the sun, does reverse polarity on time scales of about 400,000 years but there is no evidence that a reversal, which takes thousands of years to occur, will begin in 2012.

For any claims of disaster or dramatic changes in 2012, the burden of proof is on the people making these claims. Where is the science? Where is the evidence? There is none, and all the passionate, persistent and profitable assertions, whether they are made in books, movies, documentaries or over the Internet, cannot change that simple fact. There is no credible evidence for any of the assertions made in support of unusual events taking place in December 2012.

You don't always have a rocket to do rocket science. Sometimes a mere airplane will do – that is, a mere Boeing 747 toting a 17-ton, 9-foot wide telescope named SOFIA.

"SOFIA is set to attain some spectacular science," says scientist."For instance, this telescope will help us figure out how planets form and how our own solar system came to be."




And as a portable observatory, it can fly anywhere, anytime. SOFIA can move into position to capture especially interesting astronomical events such as stellar occultations (when celestial objects cross in front of background stars), while ground-based telescopes fastened to the "wrong" geographic locations on Earth's surface miss the show. SOFIA will fly above the veil of water vapor that surrounds Earth to take a wide-eyed look at the cosmos.

"SOFIA can able to locate the 'planetary snowline,' where water vapor turns to ice in the disk of dust and gas around young stars," says project scientist.

"SOFIA will also be able to pin down where basic building blocks like oxygen, methane, and carbon dioxide are located within the protoplanetary disk."

Unlike these space-based scopes, SOFIA can "head back to the barn" periodically for instruments to be repaired, adjusted, or even swapped out for new and improved science instruments – keeping pace with cutting edge science from a "mere" airplane.

Many of the world's river basins are not subject to precise monitoring, especially those in developing countries. The few measurements that have been taken in these areas are often uncertain, incomplete or chronologically inconsistent. This makes it difficult to construct sound hydrological models. Such models are essential to predict drought, high water and the availability of water.

The GRACE satellite and evaporation
In his research, Winsemius was able to unite the scarce 'ground-level data' from poorly monitored river basins with hydrological expertise and modern satellite data, enabling him to improve the existing hydrological models. He used satellite-based estimates of rainfall and evaporation rates and gravity measurements from the GRACE satellite and applied this to the Zambezi river basin, for example. 'This river basin provides us with an excellent opportunity to put the new methods directly into practice.'

Luangwa

The methods have proved successful. From a case study on the Upper Zambezi, it has turned out that a combination of ground-level data; data from GRACE and an expert knowledge of the hydrology of the area have produced a model with a robust structure.

‘A second case study on a sizeable tributary of the Zambezi – the Luangwa – demonstrated that the values of the model parameters can be indirectly adjusted on the basis of small amounts of data originating from the low-quality ground-level data on the one hand, and the evaporation rate estimates from the satellite measurements on the other. Of course, this leads to a considerable reduction in the uncertainty of the model,’ says Winsemius.


Spitzer Space Telescope (formerly the Space Infrared Telescope Facility [SIRTF]) is an infrared space observatory, the fourth and final of NASA's Great Observatories.

The first images taken by SST were designed to show off the abilities of the telescope and showed a glowing stellar nursery; a swirling, dusty galaxy; a disc of planet-forming debris; and organic material in the distant universe.

In March of 2006, astronomers reported an 80 light year-long nebula near the center of the Milky Way Galaxy, the Double Helix Nebula, which is, as the name implies, twisted into a double spiral shape.

This is thought to be evidence of massive magnetic fields generated by the gas disc orbiting the super massive black hole at the galaxy's center, 300 light years from the nebula and 25,000 light years from Earth.

This nebula was discovered by the Spitzer Space Telescope...

Scientific Experts from around the world are predicting with reasons that three years from now, all life on Earth could well come to an end. Some are saying it’ll be humans that would set it off. Others believe that a natural phenomenon will be the cause. And the religious folks are saying it’ll be God himself who would press the stop button. The following are some likely arguments as to why the world would end by the year 2012.

Sun stormsSolar experts from around the world monitoring the sun have made a startling discovery. Our sun is in a bit of conflict. The energy output of the sun is, like most things in nature, cyclic and it’s supposed to be in the middle of a period of relative stability. This activity is predicted to get worse and calculations suggest it’ll reach its deadly peak sometime in 2012.

The atom smasher
Scientists in Europe have been constructing the world’s largest particle accelerator. Basically, it’s a 27 km tunnel designed to smash atoms together to find out what makes the universe tick. So when this machine is fired up for its first serious experiment in 2012, the world could be crushed into a super-dense blob the size of a basketball.

Super volcano
Yellowstone National Park in United States is famous for its thermal springs and old authentic geyser. The reason for this is simple -- it’s sitting on top of the world’s biggest volcano and geological experts are beginning to get nervous sweats. The Yellowstone volcano has a pattern of erupting every 650,000 years. The pressure under the Yellowstone is building steadily, and geologists have set 2012 as a likely date for the big bang.

The physicists
Physicists at Berkely Academy have been crunching the numbers. Even worse, they’re claiming that their calculations prove that we’re all going to die, very soon. They are also saying that their prediction comes with a certainty of 99 per cent; and 2012 just happens to be the best guess as to when it occurs.

Earth’s magnetic field
We all know that the Earth is surrounded by a magnetic field that shields us from most of the sun’s radiation. Scientists have noted that the poles are drifting apart roughly 20-30 kms each year, much faster than ever before, which points to a pole-shift being right around the corner. The result is enough UV outdoors to crisp your skin in seconds, killing everything it touches.




Once upon a time — roughly four billion years ago — Mars was warm and wet, much like Earth. Liquid water flowed on the Martian surface in long rivers that emptied into shallow seas. A thick atmosphere blanketed the planet and kept it warm. Living microbes might have even arisen, some scientists believe, starting Mars down the path toward becoming a second life-filled planet next door to our own.


Mars today is bitter cold and bone dry. The rivers and seas are long gone. Its atmosphere is thin and wispy, and if Martian microbes still exist, they're probably eking out a meager existence somewhere beneath the dusty Martian soil.

One way or another, scientists believe, Mars must have lost its most precious asset: its thick atmosphere of carbon dioxide. CO2 in Mars's atmosphere is a greenhouse gas, just as it is in our own atmosphere. A thick blanket of CO2 and other greenhouse gases would have provided the warmer temperatures and greater atmospheric pressure required keeping liquid water from freezing solid or boiling away.

Over the last four billion years, Mars somehow lost most of that blanket. Scientists have proposed various theories for how that loss happened. Perhaps an asteroid impact blew most of the atmosphere into space in one catastrophic event. Or maybe erosion by the solar winds — a stream of charged particles emanating from the sun — could have slowly stripped the atmosphere away over eons. The planet's surface might also have absorbed the CO2 and locked it up in minerals such as carbonate.

The mission will be a big step toward understanding what happened to Mars — how it ended up so cold and dry after such a warm and watery beginning.

The MESSENGER spacecraft's third flyby of the planet Mercury has given scientists, for the first time, an almost complete view of the planet's surface and revealed some dramatic changes in Mercury's comet-like tail.

The bright region in the upper-right corner of the image surrounds a suspected explosive volcanic vent. The 290-km-diameter double-ring basin near the bottom of the image has a smooth interior that may be the result of effusive volcanism.

"A striking illustration of what we call 'seasonal' effects in Mercury's exosphere is that the neutral sodium tail, so prominent in the first two flybys, is now significantly reduced in extent," says participating scientist Ron Vervack of the Johns Hopkins University Applied Physics Laboratory in Laurel, Md.

Approximately 98 percent of Mercury's surface now has been imaged by NASA spacecraft. After MESSENGER goes into orbit, it will see the Polar Regions, which are the only remaining unobserved areas of the planet.


An armada of robots may one day fly above the mountain tops of Saturn's moon Titan, cross its vast dunes and sail in its liquid lakes.

Wolfgang Fink, visiting associate in physics at the California Institute of Technology in Pasadena says we are on the brink of a great paradigm shift in planetary exploration, and the next round of robotic explorers will be nothing like what we see today.

"The way we explore tomorrow will be unlike any cup of tea we've ever tasted," said Fink, who was recently appointed as the Edward and Maria Keonjian Distinguished Professor in Microelectronics at the University of Arizona, Tucson. "We are departing from traditional approaches of a single robotic spacecraft with no redundancy that is Earth-commanded to one that allows for having multiple, expendable low-cost robots that can command themselves or other robots at various locations at the same time."

Fink and his team members at Caltech, the U.S. Geological Survey and the University of Arizona are developing autonomous software and have built a robotic test bed that can mimic a field geologist or astronaut, capable of working independently and as part of a larger team. This software will allow a robot to think on its own, identify problems and possible hazards, determine areas of interest and prioritize targets for a close-up look.

The way things work now, engineers command a rover or spacecraft to carry out certain tasks and then wait for them to be executed. They have little or no flexibility in changing their game plan as events unfold; for example, to image a landslide or cryovolcanic eruption as it happens, or investigate a methane outgassing event.

"In the future, multiple robots will be in the driver's seat," Fink said. These robots would share information in almost real time. This type of exploration may one day be used on a mission to Titan, Mars and other planetary bodies. Current proposals for Titan would use an orbiter, an air balloon and rovers or lake landers.

In this mission scenario, an orbiter would circle Titan with a global view of the moon, with an air balloon or airship floating overhead to provide a birds-eye view of mountain ranges, lakes and canyons. On the ground, a rover or lake lander would explore the moon's nooks and crannies. The orbiter would "speak" directly to the air balloon and command it to fly over a certain region for a closer look. This aerial balloon would be in contact with several small rovers on the ground and command them to move to areas identified from overhead.

"This type of exploration is referred to as tier-scalable reconnaissance," said Fink. "It's sort of like commanding a small army of robots operating in space, in the air and on the ground simultaneously."

A rover might report that it's seeing smooth rocks in the local vicinity, while the airship or orbiter could confirm that indeed the rover is in a dry riverbed - unlike current missions, which focus only on a global view from far above but can't provide information on a local scale to tell the rover that indeed it is sitting in the middle of dry riverbed.

A current example of this type of exploration can best be seen at Mars with the communications relay between the rovers and orbiting spacecraft like the Mars Reconnaissance Orbiter. However, that information is just relayed and not shared amongst the spacecraft or used to directly control them.

"We are basically heading toward making robots that command other robots," said Fink, who is director of Caltech's Visual and Autonomous Exploration Systems Research Laboratory, where this work has taken place.

"One day an entire fleet of robots will be autonomously commanded at once. This armada of robots will be our eyes, ears, arms and legs in space, in the air, and on the ground, capable of responding to their environment without us, to explore and embrace the unknown," he added.

Papers describing this new exploration are published in the journal "Computer Methods and Programs in Biomedicine" and in the Proceedings of the SPIE.