Science & TechnologyS


Cloud Lightning

Sun Rules Earth's Mysterious "Night Shining" Clouds

Noctilucent CLouds
© FLPAMysterious 'night shining' clouds have a solar controller.
The comings and goings of noctilucent or "night shining" clouds in the extreme upper atmosphere may be linked to the sun's rotation.

Noctilucent clouds appear about 80 kilometres above the Earth in each hemisphere's summer. Their extent and brightness varies over days, weeks and years, but no one knows why.

Now Charles Robert of the University of Bremen, Germany, and colleagues think they have an answer. By measuring changes in the light reflected from the clouds, they found that the clouds appear to wax and wane in prevalence over a 27-day cycle. As the sun takes 27 days to rotate around its axis, the team suggest a link (Journal of Geophysical Research, DOI: 10.1029/2009jd012359).

Info

Magnetic poles may once have been at equator

Magnetic Poles
© Los Alamos National LaboratoryMagnetic poles haven't always been here.
Did the Earth's magnetic poles once lie near the equator? That could explain puzzling changes in the magnetism of rocks millions of years ago.

The Earth's magnetic poles are aligned along roughly the same axis as its rotational poles. Geologists have assumed this was also true in the past, so they use volcanic rocks, which when they formed took on an imprint of the direction and strength of the Earth's magnetic field, to infer the rocks' original latitude and to trace continental motions over the past billion years.

But doing this for rocks in North America and eastern Europe is turning up a conundrum. In both regions, there appear to be rocks that were at the equator at some points between 550 and 600 million years ago and near the poles for other parts of this time period.
There appear to be rocks that moved from the poles to the equator several times in 50 million years.

Sherlock

Greco-Roman Mummy, Tombs Uncovered in Egypt Oasis

Image
© Agence France-PresseThe one metre long gypsum sarcophagus portrays a woman dressed in Roman robes and contains a mummified woman or girl
Egyptian archaeologists carrying out excavations at the site of a planned youth center have found 14 tombs dating back to the third century BC, including one with a female mummy adorned with jewelry.

The Greco-Roman tombs, in Bahariya Oasis, 300 km (190 miles) southwest of Cairo, were discovered during probes that indicated they may be part of a much larger necropolis, Egypt's Culture Ministry said in a statement Monday.

A 97-cm (38-inch) tall female mummy, found in the stair-lined interior of one of the rock-hewn tombs, was cast in colored plaster inlaid with jewelry and eyes.

Archaeologists, who dug at the site ahead of the planned construction of a youth center, found the tombs contained other treasures as well. The area has now been turned over to Egypt's antiquities authority.

Magnify

Battery Breakthrough Technology Could Power Homes for Pennies Per Kilowatt Hour

Image
© Ashley FranscellCeramatec President Ashok V. Joshi and his team John Gordon (from left to right), John Watkins, Grover Coors and Anthony Nickens at Ceramatec in Salt Lake City.
Scientists with Ceramatec, the research and development arm of CoorsTek, say that they have developed a new kind of deep-storage battery that, when coupled with on-site power generation mechanisms like wind and solar electricity, could power an entire home for only pennies per kilowatt hour.

Most wind and solar-powered homes remain connected to the national electric grid, largely because it is difficult and expensive to install batteries large enough to keep the house powered through low wind or sun periods. Ceramatec's new battery, however, uses solid materials to store between 20 and 40 kilowatt hours of electricity at temperatures of only 90 degrees Celsius. In contrast, most high-density batteries use liquids heated to dangerous temperatures of roughly 600 degrees.

The batteries are currently being tested to see how many charge-discharge cycles they can support throughout their lifetimes. Currently the batteries have made it through 200 and are still going strong, and the scientists estimate a lifespan of 3,650 cycles -- or one cycle every day for 10 years. Since each battery costs approximately $2,000, this would translate into a cost of only three cents per kilowatt hour -- in contrast to the eight cents per kilowatt hour charged by the typical electric company.

Pharoah

Scientists Discover 'Blue' Mystery of Ancient Egypt

Egyptian Pottery
© Colin A. Hope/Monash UniversityPottery decorated in a distinctive pale blue color was in vogue in New Kingdom Egypt, particularly during the reign of Amenhotep III and Ramesses II.
While most Egyptian pottery was undecorated, during the New Kingdom - Egypt's Golden Age - a variety of pottery was elegantly decorated in a distinctive pale blue.

The pottery has been found at many sites in Egypt, the Middle East, and Sudan, with most of it being in Egypt. Given the restricted use of the blue paint, it probably was available only to artisans associated with major royal residences.

To obtain an uncontaminated sample of the blue paint for chemical analysis, Dr. Jennifer Smith, who is an associate professor at Washington University in St. Louis (WUSTL), Dr. Colin Hope, associate professor and director of the Center for Archaeology and Ancient History at Monash University in Australia, and Paul Kucera, a doctoral student at Monash University, belly-crawled through a long, narrow tunnel at a desert oasis. The tunnel was carved in the rock by Egyptians at the time of the pharaohs.

Although some Egyptian sculptures were colored by adding ground copper to ground quartz, the pale blue pottery was thought to be decorated by cobalt.

Camera

Shuttle Cloud

Image
© Howard CohenPhoto details: Canon EOS 5D Mark II, 190 seconds, ISO 800
On April 5th, space shuttle Discovery blasted off from Cape Canaveral at the crack of dawn. The shuttle began its journey in darkness--the sun was still below the horizon--but moments after it left the pad, Discovery burst into high altitude sunlight and proceeded to put on an extraordinary show. University of Florida astronomy professor Howard Cohen describes what he saw from his home in Gainesville, more than 130 miles from the Cape.

"The launch began in typical fashion- a brilliant, yellowish glow rising out of the southwest gradually morphing into a white contrail. Impatient observes might have thought that was it. But then an amazing contrail, the likes of which I have never seen before, rapidly appeared around and following the shuttle's path. For a short time it resembled a comet streaking across the dawn sky." He took this picture using his Canon EOS 5D.

Comment: For more information, see SOTT's Best of the Web Article: Cosmic Climate Change: Space Shuttle Discovery - STS 131 leaves spectacular dragon trails in the sky


Sun

Today The Sun Had A Comet For Breakfast

Image
© SOHO
The icy visitor from the outer solar system appeared with no warning on April 9th and plunged into the sun during the early hours of April 10th. One comet went in, none came out. The Solar and Heliospheric Observatory (SOHO) had a good view of the encounter.

The comet was probably a member of the Kreutz sungrazer family. Named after a 19th century German astronomer who studied them in detail, Kreutz sungrazers are fragments from the breakup of a giant comet at least 2000 years ago. Several of these fragments pass by the sun and disintegrate every day. Most are too small to see but occasionally a big fragment like today's attracts attention.

Satellite

Spacecraft Spots Active Volcanoes on Venus

Image
© NASASurface heat data from the Venus Express spacecraft show volcanic activity on Venus
Venus is alive.

Researchers using data from the European Space Agency's Venus Express spacecraft said they spotted three active volcanoes that recently poured red hot lava onto the planet's already broiling surface.

The discovery, announced in a paper published Friday online in Science, suggests that Venus - like the Earth - is periodically resurfaced by lava flows, explaining why it seems devoid of craters.

"We estimate the flows to be younger than 2.5 million years, and probably much younger, likely 250,000 years or less, indicating that Venus is actively resurfacing," the authors write. They were led by Suzanne E. Smrekar of the Jet Propulsion Laboratory in Pasadena.

Satellite

Ice-Tracking Satellite Launched by European Agency

The European Space Agency launched its CryoSat-2 satellite on a 140 million-euro ($190 million) mission to measure the thickness of ice on Greenland, Antarctica and the polar seas.

The launch from the Baikonur Cosmodrome in Kazakhstan was aired live on ESA's Web site. It comes four years after the original satellite was lost due to a failure of the launcher. About 17 minutes after liftoff, the agency confirmed the first signal from the CryoSat-2 was received in Malindi, Kenya.

"This time the launcher worked beautifully: We are in orbit," ESA Director-General Jean-Jacques Dordain said. "It's one additional contribution from ESA to better understand the planet Earth and climate change."

United Nations scientists have highlighted melting ice as a harbinger of climate change, and in 2007 said oceans will likely rise by as much as 59 centimeters (23 inches) by 2100 as a result of global warming. The loss of sea ice can increase the rate of warming by leaving dark, heat-absorbing ocean exposed.

Vader

Trophy system seeks to destroy missiles and grenades before impact

Image
The governments of most nations around the globe spend untold sums of money developing weapons that strike at enemies with heavy force, or on a smaller scale through the use of unmanned drones. Many of these nations also spend great sums of money on defensive technologies to protect their troops from enemy weapons.

In August of 2009, Israel Defense Forces announced a new system for defense of tanks that is called the Trophy Active protection system. The system was operational at the time and undergoing extensive testing. The idea behind the Trophy system is to protect tanks from threats including missiles and rocket propelled grenades fired by enemy combatants.