Coronal Mass Ejection (CME)
as Never Seen Before
Twin NASA spacecraft have provided scientists with their first view of the speed, trajectory, and three-dimensional shape of powerful explosions from the Sun known as coronal mass ejections, or CMEs. This new capability will dramatically enhance scientists' ability to predict if and how these solar tsunamis could affect Earth.
"We believe we can now predict when a CME will hit Earth with only 3-hours of uncertainty," says Angelos Vourlidas of the Naval Research Lab, who helped develop the model. "That's a four-fold improvement over older methods."
Coronal mass ejections are billion-ton clouds of hot magnetized gas that explode away from the Sun at speeds topping a million mph. Sometimes the clouds make a beeline for Earth and when they hit they can cause geomagnetic storms, satellite outages, auroras, and power blackouts. The ability to predict the speed and trajectory of a CME is key to space weather forecasting.
FULL ARTICLE: http://earthchangesmedia.com/secure/3247.326/article-9162524781.php
The Anatomy of a Solar Explosion in 3-D
Written by Nancy Atkinson
FEROCIOUS CROISSANTS: For the first time, NASA spacecraft have traced the 3D shape of solar storms known as coronal mass ejections (CMEs). It turns out the most ferocious CMEs resemble something from a French bakery. Get the full story from Science@NASA.
SLOW-MOTION EXPLOSIONS: How deep is solar minimum? Consider this: The most powerful solar explosions are now moving in slow motion. "Lately, coronal mass ejections (CMEs) have become very slow, so slow that they have to be dragged away from the sun by the solar wind," says researcher Angelos Vourlidas of the Naval Research Lab. Here is an example from April 11th:
Each second in the SOHO animation corresponds to an hour or more of real time. "The speed of the CME was only 240 km/s," says Vourlidas. "The solar wind speed is about 300 km/s, so the CME is actually being dragged."
Vourlidas has examined thousands of CMEs recorded by SOHO over the past 13 years, and he's rarely seen such plodding explosions. In active times, CMEs can blast away from the sun faster than 1000 km/s. Even during the solar minimum of 1996, CMEs often revved up to 500 or 600 km/s. "Almost all the CMEs we've seen since the end of April 2008, however, are very slow, less than 300 km/s."
Is this just another way of saying "the sun is very quiet?" Or do slow-motion CMEs represent a new and interesting phenomena? The jury is still out. One thing is clear: solar minimum is more interesting than we thought.
Solar tsunami data will predict Earth havoc
The tsunamis -- powerful explosions known as coronal mass ejections, or CMEs -- produce solar cosmic rays that can interfere with technology, causing power blackouts and disrupting air traffic communications and cell phone networks.
NASA says images captured by its twin Solar Terrestrial Relations Observatory, or STEREO, spacecraft have enabled scientists to map the tsunamis in 3D to examine their structure, velocity, mass and direction.
The solar ejections, its says, can release billions of tons of high-velocity plasma into space, producing a shockwave that generates cosmic rays which then plow into our atmosphere.
These can create the brightly-colored auroras, more commonly known as the Northern or Southern lights, but also have more damaging effects, posing particular threats to spacecraft and astronauts.
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Solar physicist Angelos Vourlidas of the Naval Research Laboratory in Washington said the new data from the STEREO craft -- launched into orbit in October 2006 -- will revolutionize the study of cosmic weather patterns.
"Before this unique mission, measurements and the subsequent data of a CME observed near the sun had to wait until the ejections arrived at Earth three to seven days later," he said in statement.
"Now we can see a CME from the time it leaves the solar surface until it reaches Earth and we can reconstruct the event in 3D directly from the images
Exactly 20 years from today, an asteroid about the size of a 25-story building will come closer to Earth than the networks of communications satellites orbiting the planet. Astronomers don't yet know if Apophis' second visit will be a rendezvous or a collision, as its orbit will be bent by Earth's gravity during the 2029 flyby. "It can't even be said for certain what side of the sun (the asteroid) will be on in," said Jon Giorgini, a senior analyst with the Solar System Dynamics group at NASA's Jet Propulsion Laboratory in Pasadena, Calif. Most of the rocks whizzing around Earth are too small to do damage even if they were on collision paths. "Things much below 30 meters in size don't pose much of a threat at all since the atmosphere protects us," said Nick Kaiser, lead scientist of a new University of Hawaii asteroid-hunting project known as the Panoramic Survey Telescope and Rapid Response System, or Pan-STARRS.
Spacecraft Will Search for Evidence of a Hypothetical Lost Planet
Astronomers are hoping to catch a glimpse of debris that could be leftover from a cosmic collision between our Earth and a Mars-sized planet called Theia–if, in fact, it existed at all. “It’s a hypothetical world. We’ve never actually seen it, but some researchers believe it existed 4.5 billion years ago — and that it collided with Earth to form the moon,” said Mike Kaiser, a NASA scientist [SPACE.com]. The research will be done with the two Stereo spacecraft that are on their way to observe the sun; on their way they’ll have a chance to do some “bonus science,” as one researcher called it. The spacecraft are passing through two regions of space, called Lagrangian points, where the gravity from the Earth and the sun combine to form wells that tend to collect solar system detritus…. Scientists think Theia may even have formed in one of these gravitational points of balance from the accumulation of flotsam that had built up there [SPACE.com].
According to one theory of our moon’s origin, the gravitational pull of Venus may have tugged Theia out of its stable spot, and sent it careening into Earth. The glancing blow stripped the impactor of its outer layer, along with some of Earth’s. Its iron core is thought to have melted and much of it merged with Earth’s iron core. The outer material – mostly belonging to the impactor – gathered itself together and formed the moon. [This theory] explains why the moon has such a tiny iron core. It also explains why the the geochemistry of Earth and moon materials are so similar – they formed in the same region of the nebula of dust and gas that surrounded the early sun [The Christian Science Monitor].
Astronomers have looked for large “Theiasteroids” in the Lagranian points with ground-based telescopes, with little success. But the Stereo spacecraft will have a better view that will allow it to search for smaller asteroid chunks. The spacecraft pair will also study the mineral composition of any asteroids it sights to determine if they’re chemically similar to Earth or the moon.
David J. Smith goes over some discovery's of ancient times. Learn about the power grid that the people before the flood had. Find out about power points and Ley Lines, What were the pyramids really used for? Are were really evolving up or have we had this technology in the past?
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