Heavens

Agricultural fires are set all over the world at different times to prepare the soil for the planting of new crops. In India and Nepal several dozens agricultural fires have been set and are burning in this image from April 06, 2013. This natural-color satellite image was collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Aqua satellite. Actively burning areas, detected by MODIS's thermal bands, are outlined in red.

The sun emitted a mid-level flare, peaking at 3:16 a.m. EDT on April 11, 2013.

Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel. This disrupts the radio signals for as long as the flare is ongoing, anywhere from minutes to hours.

Fires purposely set to burn crop residues and get the land ready for the growing season are continuing as evidenced in this image from the MODIS instrument on the Aqua satellite. A longer, more detailed account of these types of fires can be found at this URL: http://www.nasa.gov/mission_pages/fires/main/world/20130326-indochina.html.

Many plumes of smoke from fires burning across the southeastern United States of America can be seen here. The fires are affecting several states including Alabama, Georgia and South Carolina, and Florida.

There are currently over 1000 new fires in the past week across the South. There were 17 new large fires with 3 being uncontained as well as numerous smaller ones. A "large fire" is defined by the National Interagency Fire Center (NIFC) as a wildfire of 100 acres or more occurring in timber, or a wildfire of 300 acres or more occurring in grass/sage.

In order to improve a simulation designed to study the evolution of the solar system through time, numerical mathematical methods have been developed at the Computing Faculty of the University of the Basque Country (UPV/EHU). Specifically, the methods proposed enable the simulation calculations to be done faster and more accurately.

Chicago (April 10, 2013)—A major challenge facing today's health care community is to find ways to lower costs without compromising clinical quality. Taking that challenge to task, researchers at Medstar Health and Georgetown University School of Medicine, Washington DC, report success in using a concept called "value-based analysis," which simultaneously measures quality and cost and addresses inefficiencies in care.

Stars the size of the Sun end their lives as tiny and faint white dwarf stars. But as they make the final transition into retirement their atmospheres are blown away into space. For a few tens of thousands of years they are surrounded by the spectacular and colourful glowing clouds of ionised gas known as planetary nebulae.

SALT LAKE CITY, April 10, 2013 – University of Utah researchers developed a high-speed camera system that spent the past two winters photographing snowflakes in 3-D as they fell – and they don't look much like those perfect-but-rare snowflakes often seen in photos.

"Until our device, there was no good instrument for automatically photographing the shapes and sizes of snowflakes in free-fall," says Tim Garrett, an associate professor of atmospheric sciences. "We are photographing these snowflakes completely untouched by any device, as they exist naturally in the air."

In South Africa, people with HIV who start treatment with anti-AIDS drugs (antiretroviral therapy) have life expectancies around 80% of that of the general population provided that they start treatment before their CD4 count drops below 200 (cells per microliter), according to a study by South African researchers published in this week's PLOS Medicine.

The radiation environment near the Moon could be damaging to humans and electronics on future missions.

To characterize this potentially hazardous environment, the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) on board the Lunar Reconnaissance Orbiter mission, which orbits at 50 kilometers (31 miles) above the Moon's surface, measures the radiation that would be absorbed by either electronic parts or human tissue behind the shielding of a spacecraft.

Geckos are known for their sticky adhesive toes that allow them to stick to, climb on, and run along surfaces in any orientation--even upside down! But until recently, it was not well understood how geckos kept their sticking ability even on wet surfaces, as are common in the tropical regions in which most geckos live. A 2012 study in which geckos slipped on wet glass perplexed scientists trying to unlock the key to gecko adhesion in climates with plentiful rain and moisture.

Rising temperatures will lead to a massive "greening" of the Arctic by mid-century, as a result of marked increases in plant cover, according to research supported by the National Science Foundation (NSF) as part of its International Polar Year (IPY) portfolio.

The greening not only will have effects on plant life, the researchers noted, but also on the wildlife that depends on vegetation for cover. The greening could also have a multiplier effect on warming, as dark vegetation absorbs more solar radiation than ice, which reflects sunlight.

A major breakthrough in measuring the structure of nanomaterials under extremely high pressure has been made by researchers at the London Centre for Nanotechnology (LCN).

Described in Nature Communications, the study used new advances in x-ray diffraction to image the changes in morphology of gold nanocrystals under pressures of up to 6.5 gigapascals.

University of Cincinnati research at the ancient Maya site of Medicinal Trail in northwestern Belize is revealing how populations in more remote areas – the hinterland societies – built reservoirs to conserve water and turned to nature to purify their water supply. Jeffrey Brewer, a doctoral student in the University of Cincinnati's Department of Geography, will present his findings on April 11, at the Association of American Geographers' annual meeting in Los Angeles.

An exploding star observed in 1604 by the German astronomer Johannes Kepler held a greater fraction of heavy elements than the sun, according to an analysis of X-ray observations from the Japan-led Suzaku satellite. The findings will help astronomers better understand the diversity of type Ia supernovae, an important class of stellar explosion used in probing the distant universe.