Mayur's Posterous

Laws of physics vary throughout the universe, new study suggests

Posted

NASA plans to send a probe to the Sun.

SOLAR SCIENCE

 

Solar Probe Plus To Plunge Directly Into Sun's Atmosphere

Solar Probe+ will likely discover new mysteries, too, in a realm that no other spacecraft has dared enter. At closest approach, Solar Probe+ will be 7 million km or 9 solar radii from the sun. There, the spacecraft's carbon-composite heat shield must withstand temperatures as high as 2000 degrees C and survive blasts of radiation that would quickly disable other missions. From these near distances inside the sun's atmosphere, the solar disk will loom 23 times wider than it does in the skies of Earth.
by Dr. Tony Phillips
Science@NASA
Huntsville AL (SPX) Sep 03, 2010
NASA's daring plan to visit the sun took a giant leap forward with the selection of five key science investigations for the Solar Probe+ spacecraft.

Slated to launch no later than 2018, the smart car-sized spacecraft will plunge directly into the atmosphere of the sun, aiming to solve some of the biggest mysteries of solar physics. The announcement means that researchers can begin building sensors for unprecedented in situ measurements of the solar system's innermost frontier.

"Solar Probe+ is going where no spacecraft has gone before," says Lika Guhathakurta, Solar Probe+ program scientist at NASA HQ. "For the first time, we'll be able to 'touch, taste and smell' the sun."

Last year, NASA invited top researchers around the world to submit proposals detailing possible science investigations for the pioneering spacecraft. Thirteen proposals were received and five have been selected:

+ SWEAP, the Solar Wind Electrons Alphas and Protons Investigation: The most abundant particles in the solar wind are electrons, protons and helium ions. SWEAP will count these particles and measure their properties, even "sweeping up" some of them in a special Solar Probe Cup for direct analysis. The principal investigator is Justin C. Kasper of the Smithsonian Astrophysical Observatory in Cambridge, Mass.

+ WISPR, the Wide-field Imager for Solar Probe Plus: WISPR is a telescope that will make 3D images of the sun's atmosphere similar to medical CAT scans. WISPR can actually see the solar wind, allowing it to image clouds and shock waves as they approach and pass the spacecraft. This telescope is an important complement to the spacecraft's in situ instruments, which sample the plasmas that WISPR images. The principal investigator is Russell Howard of the Naval Research Laboratory in Washington, DC.

+ FIELDS, The Fields Investigation for Solar Probe Plus: This instrument will make direct measurements of electric and magnetic fields, radio emissions, and shock waves which course through the sun's atmospheric plasma. FIELDS also turns Solar Probe Plus into a giant dust detector, registering voltage signatures when specks of space dust hit the spacecraft's antenna. The principal investigator is Stuart Bale of the University of California in Berkeley.

+ ISIS, Integrated Science Investigation of the Sun: The ISIS EPI-Hi and EPI-Lo instruments will monitor electrons, protons and ions which are accelerated to high energies by shock waves in the sun's atmosphere. These are the very same particles that pose a threat to astronauts in space, disable satellites, and ionize Earth's upper atmosphere.

+ Solar Probe+ Observatory Scientist: This was a proposal not for an instrument, but for a person. The principal investigator, Marco Velli, becomes the mission's Observatory Scientist. In the years ahead, he will become deeply familiar with the spacecraft and its construction, helping to ensure that adjacent in situ instruments do not interfere with one another as they sample the solar environment. He will also guide the mission's "big picture" science investigations after Solar Probe+ enters the sun's atmosphere.

"The sensors we've selected to ride aboard Solar Probe+ are designed to solve some of the biggest mysteries of solar physics," says Dick Fisher, head of NASA's Heliophysics Division in Washington DC.

Why is the sun's atmosphere is so much hotter than its surface? And what propels the solar wind?

"We've been struggling with these questions for decades," says Fisher. "Solar Probe+ should finally provide some answers."

Solar Probe+ will likely discover new mysteries, too, in a realm that no other spacecraft has dared enter. At closest approach, Solar Probe+ will be 7 million km or 9 solar radii from the sun. There, the spacecraft's carbon-composite heat shield must withstand temperatures as high as 2000 degrees C and survive blasts of radiation that would quickly disable other missions. From these near distances inside the sun's atmosphere, the solar disk will loom 23 times wider than it does in the skies of Earth.

"What will we find there?" wonders Guhathakurta. "This is truly unexplored territory." By design, Solar Probe's winning instruments are sufficiently versatile to investigate many different kinds of phenomena. Whatever comes along--be it electric or magnetic, high- or low-energy, wavy or turbulent--they should be able to measure it.

"The possibilities for discovery," she says, "are off the charts."

Here's NASA's website for the project http://solarprobe.gsfc.nasa.gov/

Posted

Joshua Tree Under the Milky Way

Timelapse video of the Perseid Meteor Shower and the galactic core of the Milky Way as seen from Joshua Tree National Park. Watch it full screen :)

Posted

BBC News - Meteor spectacle 'set to dazzle'

Media_httpnewsbbcimgc_qgghi

Posted

Astronomy Without A Telescope – Strange Stars | Universe Today

Posted

Rethinking Einstein: The end of space-time - New Scientist

Posted

- Excellent Perseid Meteor Shower Expected Aug. 11-13

Every August, just when many people go vacationing in the country where skies are dark, the best-known meteor shower — the Perseid meteor shower — makes its appearance.

The "shooting stars" promise to deliver an excellent show this year to anyone with clear and dark skies away from urban and suburban lights.

The best time to watch for meteors will be from the late-night hours of Wednesday, Aug, 11 on through the predawn hours of Aug. 13 – two full nights and early mornings. Patient skywatchers with good conditions could see up to 60 shooting stars an hour or more. [Top 10 Perseid Meteor Shower Facts]

History of the Perseids

The event is also known as "The Tears of St. Lawrence."

Laurentius, a Christian deacon, is said to have been martyred by the Romans in 258 AD on an iron outdoor stove. It was in the midst of this torture that Laurentius cried out:

"I am already roasted on one side and, if thou wouldst have me well cooked, it is time to turn me on the other."

The Saint's death was commemorated on his feast day, Aug. 10. King Phillip II of Spain built his monastery place the "Escorial," on the plan of the holy gridiron. And the abundance of shooting stars seen annually between approximately Aug. 8 and 14 have come to be known as St. Lawrence's "fiery tears."

We know today that these meteors are actually the dusty remains left behind by the comet Swift-Tuttle. Discovered back in 1862, and most recently observed in 1992, this comet takes approximately 130 years to circle the sun. With each pass, Comet Swift-Tuttle produces a debris trail along its orbit to cause the Perseids.

Every year during mid-August, when the Earth passes close to the orbit of Swift-Tuttle, the material left behind by the comet from its previous visits ram into our atmosphere at approximately 37 miles per second (60 km/second) and creates bright streaks of light in our midsummer night skies.

Excellent prospects this year

According to the best estimates, in 2010 the Earth is predicted to cut through the densest part of the Perseid stream sometime around 8:00 p.m. Eastern Daylight Time on Thursday.

The best window of opportunity to see the shower will be the late-night hours of Wednesday on through the first light of dawn on the morning of Thursday, and then again during the late-night hours of Aug. 12 into the predawn hours of Aug. 13.

The Moon, whose bright light almost totally wrecked last year's shower, will have zero impact this year; unlike last year when it was just a few days past full, this year it will be new on Monday, Aug. 9, meaning that there will be absolutely no interference from it at all.

Excellent!

What to expect

A very good shower will produce about one meteor per minute for a given observer under a dark country sky. Any light pollution or moonlight considerably reduces the count.

The August Perseids are among the strongest of the readily observed annual meteor showers, and at maximum activity nominally yields 90 or 100 meteors per hour. Anyone in a city or near bright suburban lights will see far fewer. [Video: Perseid

However, observers with exceptional skies often record even larger numbers. Typically during an overnight watch, the Perseids are capable of producing a number of bright, flaring and fragmenting meteors, which leave fine trains in their wake.

On the night of shower maximum, the Perseid radiant is not far from the famous "Double Star Cluster" of Perseus (hence the name, "Perseid"). Low in the northeast during the early evening, it rises higher in the sky until morning twilight ends observing. Shower members appearing close to the radiant have foreshortened tracks; those appearing farther away are often brighter, have longer tracks, and move faster across the sky.

About five to 10 of the meteors seen in any given hour will not fit this geometric pattern, and may be classified as sporadic or as members of some other (minor) shower.

How to watch

Aside from the predicted peak hours, Perseid meteor shower activity always increases sharply in the hours after midnight. We are then looking more nearly face-on into the direction of the Earth's motion as it orbits the sun, so the atmosphere above you scoops up meteors like the windshield of a car catching bugs. From around 2 a.m. until daybreak your local time, the Perseids promise to put on a good display, weather permitting.

Making a meteor count is as simple as lying in a lawn chair or on the ground and marking on a clipboard whenever a "shooting star" is seen. Watching for the Perseids consists of lying back, gazing up into the stars, and waiting. It is customary to watch the point halfway between the radiant (which will be rising in the northeast sky) and the zenith, though it's perfectly all right for your gaze to wander.

Counts should be made on several nights before and after the predicted maximum, so the behavior of the shower away from its peak can be determined. Usually, good numbers of meteors should be seen on the preceding and following nights as well. The shower is generally at one-quarter strength one or two nights before and after maximum.

A few Perseids can be seen as much as two weeks before and a week after the peak. The extreme limits, in fact, are said to extend from July 17 to Aug. 24, though an occasional one may be seen almost anytime during the month of August.

As a bonus every evening now through he heart of the Perseid meteor shower, three bright planets are tightly clustered just after sunset. Venus, Mars and Saturn are easy to spot in the southwestern sky as soon as darkness falls.

Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for The New York Times and other publications, and he is also an on-camera meteorologist for News 12 Westchester, New York.

 

Posted

Update: Unknown Object in Nearby Galaxy Sending Mysterious Radio Waves

Posted

Underground Antarctica Experiment Discovers Puzzling Space Ray Pattern | LiveScience

This "skymap," generated in 2009 from data collected by the IceCube Neutrino Observatory, shows the relative intensity of cosmic rays directed toward the Earth's Southern Hemisphere. Researchers from the University of Wisconsin-Madison and elsewhere identified an unusual pattern of cosmic rays, with an excess (warmer colors) detected in one part of the sky and a deficit (cooler colors) in another. Credit: IceCube collaboration, UW-Madison
Previous Image Next Image
1 of 1

This "skymap," generated in 2009 from data collected by the IceCube Neutrino Observatory, shows the relative intensity of cosmic rays directed toward the Earth's Southern Hemisphere. Researchers from the University of Wisconsin-Madison and elsewhere identified an unusual pattern of cosmic rays, with an excess (warmer colors) detected in one part of the sky and a deficit (cooler colors) in another. Credit: IceCube collaboration, UW-Madison

A puzzling pattern in the cosmic rays bombarding Earth from space has been discovered by an experiment buried deep under the ice of Antarctica.

Cosmic rays are highly energetic particles streaming in from space that are thought to originate in the distant remnants of dead stars.

But it turns out these particles are not arriving uniformly from all directions. The new study detected an overabundance of cosmic rays coming from one part of the sky, and a lack of cosmic rays coming from another.

This odd pattern was detected by the IceCube Neutrino Observatory, an experiment still under construction that is actually intended to detect other exotic particles called neutrinos. In fact, scientists have gone out of their way to try to block out all signals from cosmic rays in order to search for the highly elusive neutrinos, which are much harder to find.

Yet in sifting through their cosmic-ray data to try to separate it from possible neutrino signals, the researchers noticed the intriguing pattern.

"IceCube was not built to look at cosmic rays. Cosmic rays are considered background," said University of Wisconsin-Madison researcher Rasha Abbasi in a statement. "However, we have billions of events of background downward cosmic rays that ended up being very exciting."

Previous studies have found a similar lopsidedness (called anisotropy) in the sky over the Northern Hemisphere, but this was the first time scientists saw that the pattern extended to the southern sky visible from Antarctica.

"At the beginning, we didn't know what to expect," Abbasi said. "To see this anisotropy extending to the Southern Hemisphere sky is an additional piece of the puzzle around this enigmatic effect — whether it's due to the magnetic field surrounding us or to the effect of a nearby supernova remnant, we don't know."

One idea to explain the asymmetry is that a star may have recently died in a supernova explosion relatively nearby, and its remnant may be pouring out loads of cosmic rays that would dominate the signals we receive.

Whether or not the mystery gets solved, the observations could help scientists understand more about how cosmic rays are formed in the first place. Growing consensus favors the supernova remnant idea, though the details are not hammered out. Scientists think that the shells around dead stars, made of puffed-out layers of gas that were expelled by the star before it exploded, contain strong magnetic fields that may act as cosmic particle accelerators, speeding up particles to close to the speed of light.

"This is exciting because this effect could be the 'smoking gun' for our long-sought understanding of the source of high-energy cosmic rays," Abbasi said.

IceCube's findings on cosmic rays are detailed in a paper published Aug. 1 in the Astrophysical Journal Letters.

 

Posted

Our world may be a giant hologram.

Article can be found here : quantumconsciousness.org

 

Posted