Live in a large city like New York, London, Beijing or Mumbai, and you are likely exposed to more air pollution than people in smaller cities in surrounding areas. But exactly how a city's pollution relates to the size of its population has never been measured, until now.
Using satellite observations, NASA scientists directly measured air pollution's dependence on population in four of the planet's major air pollution regions: the United States, Europe, China and India.
NASA has accepted ownership of its newest Tracking and Data Relay Satellite (TDRS) from Boeing after successfully completing in orbit testing. TDRS-K, will be renamed TDRS-11 upon entry into service.
"This is a major step in replenishing an aging TDRS fleet which is essential in providing communications to support space exploration," said Badri Younes, deputy associate administrator for Space Communications and Navigation at NASA Headquarters. "We look forward to the launch of two additional satellites in the next few years to complete the replenishment program."
Reservoirs of silica-rich magma – the kind that causes the most explosive volcanic eruptions – can persist in Earth's upper crust for hundreds of thousands of years without triggering an eruption, according to new University of Washington modeling research.
That means an area known to have experienced a massive volcanic eruption in the past, such as Yellowstone National Park, could have a large pool of magma festering beneath it and still not be close to going off as it did 600,000 years ago.
Several fires are currently raging in central and northern California. These fires can be seen in this natural-color Terra satellite image taken by the MODIS instrument on August 18, 2013.
NASA's Aqua satellite passed over the tropical cyclone known as Pewa after it strengthened into a typhoon in the northwestern Pacific Ocean. The Aqua satellite image revealed that Pewa had developed a small eye.
On Sunday, Aug. 18, Pewa was a tropical storm when it crossed the International Date Line and moved from the Central Pacific to the Northwestern Pacific Ocean. Pewa now falls under the forecast authority of the Joint Typhoon Warning Center.
Tropical Storm Trami appears to be a very large storm in infrared data from NASA's Aqua satellite. In a NASA image, Trami appears to be about two-thirds the size of the Philippines. Satellite data also indicates that the massive storm is now making a U-turn in the Northwestern Pacific Ocean, from a southeastern path to a northwestern path.
The thirteenth Tropical Depression of the Northwestern Pacific Ocean season didn't last long. In fact, Tropical Depression 13W lived for less than a day as a depression before fizzled.
TD13W was "born" at 1500 UTC/11 a.m. EDT on Aug. 17 with maximum sustained winds near 25 knots. Later that day at 2100 UTC/5 p.m. EDT, the Joint Typhoon Warning Center issued its final bulletin on the depression. At that time it was located near 28.0 north latitude and 126.0 east longitude, about 109 nautical miles northwest of Kadena Air Base, Japan.
Fires continue to ignite parts of the West. In this image, fires in Idaho and Wyoming can be seen.
The Hardluck Fire was started by lightning on July 17, 2013 deep in the wilderness. The small two acre fire was discovered on July 20 by a fire detection flight, but the inaccessible terrain precluded sending crews in safely. Now the fire is almost 20,000 acres in size, and increasing in size and activity due to winds from the southwest. Warm dry weather is forecast for the next 2-3 days so the fire is expected to burn actively.
NASA's Aqua satellite has been busy capturing temperature data from developing tropical cyclones around the world. Aqua captured an image of Tropical Storm Unala in the central Pacific Ocean where it formed early today, Aug. 19. Over several hours, Unala moved into the northwestern Pacific where it quickly weakened to a depression.
Fires have been burning out of control on the Portuguese island of Madeira. The fire that broke out in the early hours of the morning on August 16, 2013 above the village of Monte became stronger towards noontime as intense heat and the wind made the flames spread.
In a discovery that could have major implications for the aerospace, automotive and electronics industries, scientists have found a way to dramatically reduce the corrosion rate of lightweight wonder metal magnesium: adding arsenic.
Weighing in at two thirds less than aluminium, magnesium is the lightest structural metal. It has many potential industrial applications, but uptake is severely restricted by its poor resistance to corrosion. Identification of methods to restrict magnesium corrosion is the first step in engineering such technology into functional alloys.
NASA's Aqua satellite passed over two developing low pressure areas in the Central Pacific Ocean, just before one of them strengthened into Tropical Storm Pewa.
The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Aqua satellite detected dozens of fires burning in southeastern Africa in mostly Mozambique and Malawi. The fires are outlined in red.
The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Aqua satellite detected dozens of fires burning in eastern Russia in this satellite image captured on August 15, 2013. The fires are outlined in red. Smoke appears as grayish, wispy air currents.
Analysis of an ice core taken by the National Science Foundation- (NSF) funded West Antarctic Ice Sheet (WAIS) Divide drilling project reveals that warming in Antarctica began about 22,000 years ago, a few thousand years earlier than suggested by previous records.
This timing shows that West Antarctica did not "wait for a cue" from the Northern Hemisphere to start warming, as scientists had previously supposed.