Monday, October 24, 2011

Midwestern USA at Night with Aurora Borealis

The artificial light from human settlements appears with a characteristic yellow tinge. The green light of the aurora borealis also shines brightly in this view—even seeming to reflect off Earth’s surface in Canada. A small white patch of light is almost certainly lightning from a storm on the East coast (image top right). Part of the ISS appears across the top of the image.

This astronaut photograph highlights the Chicago metropolitan area as the largest cluster of lights, next to the dark patch of Lake Michigan. The other largest metropolitan areas include St. Louis, Minneapolis–St. Paul, and the Omaha–Council Bluffs region on the Nebraska–Iowa border. The northeastern seaboard lies just beyond the Appalachian Mountains, a dark winding zone without major cities.

City light clusters give an immediate sense of relative city size. Demographers have used nighttime satellite imagery to make estimates of city populations, especially in the developing world, where growth can be rapid.

The sense of scale changes significantly in oblique views. Des Moines is 200 kilometers from Omaha and 375 kilometers from Minneapolis, yet the distances appear roughly the same in this view

Friday, October 21, 2011

NASA Invites Students to Study the Sun During Solar Week


Nasa invited students for Solar Week Fall 2011, October 17-21 – a lively week of online activities and curriculum for students about the Sun, including games and lesson plans for the whole week. In addition, there’s a message board where your classroom can submit a question to leading solar scientists.

Every fall and spring since 2000, Solar Week has provided a weeklong series of Web-based educational classroom activities and games geared for upper elementary, middle and early high school students with a focus on our dynamic Sun and its effects on Earth. Students learn about solar eclipses, sunspots, solar flares and solar storms through a series of activities, games, and lessons.

Solar Week is ideal for students studying the solar system, the stars, or astronomy in general. It's also for kids wondering what it's like being a scientist, and pondering possible career choices. Participation makes for a fun computer lab activity as well. After doing the activities, students can interact on the bulletin board with leading scientists at the forefront of Sun-Earth research. It’s a great place for any student interested in our nearest star, the Sun!

Solar Week is a collaboration between University of California, Berkeley and Rice University.

Wednesday, October 19, 2011

Mid-Latitude Cyclone over the United States

At 3:05 p.m. Eastern Daylight Time on September 26, 2011, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite observed a mid-latitude cyclone over the mid western United States. The center of the storm appeared immediately west of Lake Michigan.

Mid-latitude cyclones drive most of the stormy weather in the continental United States. Development of these cyclones often involves a warm front from the south meeting a cold front from the north. In the Northern Hemisphere, cyclones move in a counterclockwise direction. (In the Southern Hemisphere, cyclones are clockwise.) The bands of cold and warm air wrap around a center of low pressure, and air rising near the center spurs the development clouds and precipitation.

Justin Berk, a meteorologist based in Baltimore, explains that in this region, “cold air eventually wins out and wraps completely around a storm. This is called a ‘cold core’ storm and has cut itself off from the main flow of the jet stream.” This, says Berk, is why the September 26 storm appears stalled near Chicago.


Monday, October 17, 2011

Dunphy Complex Fires in Nevada

Ignited by lightning on September 30, 2011, the three fires in the Dunphy Complex raced through sagebrush and grass in northern Nevada during the first week of October. By October 6, the fires had burned 204,487 acres in a remote area between the towns of Elko and Winnemucca.

The Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite took this image on October 3 when gusty winds pushed the fires to double their size. Active fires are outlined in red.

Dense smoke rises from the Indian Creek fire, the largest of the three in the complex. The smoke blows north into northern Idaho, before becoming too thin to be seen in the satellite image. The Chukkar Canyon and Izzenhood fires show less activity, but dark, charred land reveals where the fires burned.

On October 3, the fast-moving fires grew from a collective 88,000 acres to 160,000 acres and forced the evacuation of the community of Tuscarora. They also caused power outages at mining operations in the region, reported the Elko Interagency Dispatch Center. The Dunphy Complex became the top priority for wild land fire fighters in the United States that day. Cooler weather and rain helped suppress the fires from October 4 through October 6.

Sunday, October 16, 2011

Parinacota Volcano in South America

Volcan Parinacota (“flamingo lake” in the Aymara language) is a potentially active stratovolcano located on the Altiplano, a high plateau in the Andes mountains of west-central South America. While no direct observations of eruptive activity have been recorded, surface exposure dating of lava flows suggests that activity occurred as recently as 290 AD (± 300 years). Local Aymara stories also suggest that the volcano has erupted within the past 1000 years.

This astronaut photograph from the International Space Station highlights the symmetrical cone of Parinacota, with its well-developed summit crater (elevation 6,348 meters, or 20,827 feet, above sea level). Dark brown to dark gray surfaces to the east and west of the summit include lava flows, pyroclastic deposits, and ash.

A companion volcano, Pomerape, is located across a low saddle to the north. This volcano last erupted during the Pleistocene Epoch (approximately 3 million to 12,000 years ago). Together, Parinacota and Pomerape form the Nevados de Payachata volcanic area. The summits of both volcanoes are covered by white snowpack and small glaciers.

Eruptive activity at Parinacota has directly influenced development of the local landscape, beyond the placement of volcanic deposits. Approximately 8,000 years ago, the western flank of the volcano collapsed, creating a debris avalanche that traveled 22 kilometers (14 miles) to the west. The debris blocked rivers and streams, leading to the formation of ChungarĂ¡ Lake to the south (lower left). The uneven, hummocky surface of the avalanche debris provides ample catchments for water, as evidenced by the numerous small ponds and Cotacotani Lake to the west.

Friday, October 14, 2011

NASA's Kepler Mission Discovers - World Orbiting Two Stars


The existence of a world with a double sunset, as portrayed in the film Star Wars more than 30 years ago, is now scientific fact. NASA's Kepler mission has made the first unambiguous detection of a circumbinary planet -- a planet orbiting two stars -- 200 light-years from Earth.

Unlike Star Wars’ Tatooine, the planet is cold, gaseous and not thought to harbor life, but its discovery demonstrates the diversity of planets in our galaxy. Previous research has hinted at the existence of circumbinary planets, but clear confirmation proved elusive. Kepler detected such a planet, known as Kepler-16b, by observing transits, where the brightness of a parent star dims from the planet crossing in front of it.

"This discovery confirms a new class of planetary systems that could harbor life," Kepler principal investigator William Borucki said. "Given that most stars in our galaxy are part of a binary system, this means the opportunities for life are much broader than if planets form only around single stars. This milestone discovery confirms a theory that scientists have had for decades but could not prove until now."

Tuesday, October 11, 2011

NASA Awards Historic Green Aviation Prize

NASA has awarded the largest prize in aviation history, created to inspire the development of more fuel-efficient aircraft and spark the start of a new electric airplane industry. The technologies demonstrated by the CAFE Green Flight Challenge, sponsored by Google, competitors may end up in general aviation aircraft, spawning new jobs and new industries for the 21st century.

The first place prize of $1.35 million was awarded to team Pipistrel-USA.com of State College, Pa. The second place prize of $120,000 went to team eGenius, of Ramona, Calif.

Fourteen teams originally registered for the competition. Three teams successfully met all requirements and competed in the skies over the Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. The competition was managed by the Comparative Aircraft Flight Efficiency (CAFE) Foundation under an agreement with NASA.

"NASA congratulates Pipistrel-USA.com for proving that ultra-efficient aviation is within our grasp," said Joe Parrish, NASA's acting chief technologist at NASA Headquarters in Washington. "Today we've shown that electric aircraft have moved beyond science fiction and are now in the realm of practice."

Monday, October 10, 2011

Fires in Russia and China

Fires in Russia and China

Smoke clouds the skies across northeastern China and southeastern Russia in this image taken on October 8, 2011, by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite. Widespread fires are marked in red.

The dry, windy weather of autumn created hazardous fire conditions in northeast China. On October 9, officials in Heilongjiang, the province shown here, raised the fire alert level to its second-highest level, said Xinhua news. Russian officials, meanwhile, reported monitoring four large wildfires in the Far Eastern Federal District, which includes the area shown here.

NASA Tests Deep Space J-2X Rocket Engine at Stennis

Space J-2X Rocket EngineNASA conducted a 40-second test of the J-2X rocket engine Sept. 28, the most recent in a series of tests of the next-generation engine selected as part of the Space Launch System architecture that will once again carry humans into deep space. It was a test at the 99 percent power level to gain a better understanding of start and shutdown systems as well as modifications that had been made from previous test firing results.

The test at NASA's John C. Stennis Space Center in south Mississippi came just two weeks after the agency announced plans for the new SLS to be powered by core-stage RS-25 D/E and upper-stage J-2X engines. The liquid hydrogen/liquid oxygen J-2X is being developed for NASA's Marshall Space Flight Center in Huntsville, Ala., by Pratt & Whitney Rocketdyne.

Saturday, October 08, 2011

NASA's Moon Twins Going Their Own Way

NASA's Moon Twins Going Their Own WayNASA's Gravity Recovery And Interior Laboratory (GRAIL)-B spacecraft successfully executed its first flight path correction maneuver Wednesday, Oct. 5. The rocket burn helped refine the spacecraft's trajectory as it travels from Earth to the moon and provides separation between itself and its mirror twin, GRAIL-A. The first burn for GRAIL-A occurred on Sept. 30.

"Both spacecraft are alive and with these burns, prove that they're kicking too, as expected," said David Lehman, GRAIL project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "There is a lot of time and space between now and lunar orbit insertion, but everything is looking good."

GRAIL-B's rocket burn took place on Oct. 5 at 11 a.m. PDT (2 p.m. EDT). The spacecraft's main engine burned for 234 seconds and imparted a velocity change of 56.1 mph (25.1 meters per second) while expending 8.2 pounds (3.7 kilograms) of propellant. GRAIL-A's burn on Sept. 30 also took place at 11 a.m. PDT. It lasted 127 seconds and imparted a 31.3 mph (14 meters per second) velocity change on the spacecraft while expending 4 pounds (1.87 kilograms) of propellant.

These burns are designed to begin distancing GRAIL-A and GRAIL-B's arrival times at the moon by approximately one day and to insert them onto the desired lunar approach paths.

For more information about GRAIL visit: http://www.nasa.gov/grail and http://grail.nasa.gov .

Thursday, October 06, 2011

Dust Storm over Northeastern Afghanistan

Dust Storm over Northeastern AfghanistanA dust storm spanning hundreds of kilometers stretched from northern Afghanistan into neighboring countries in early October 2011. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this natural-color image on October 5, 2011.

In places, the dust is thick enough to completely hide the land surface below, especially over southern Tajikistan and northeastern Afghanistan. In mountainous northeastern Afghanistan, dust-clogged air infiltrates valleys while skies over mountain peaks remain clear.

Sandy deserts extend from Turkmenistan into Uzbekistan and northern Afghanistan, providing material for dust plumes. Clouds fringe eastern margin of this dust storm, and the clouds could result from the same weather system that stirred the dust.

Long Cold Spell Leads to First Arctic Ozone Hole

Long Cold Spell Leads to First Arctic Ozone Hole

The Microwave Limb Sounder (MLS) looks through the edge of Earth’s atmosphere to measure gases, in this case ozone and chlorine monoxide, one of the most dominant ozone-destroying gases. These MLS images of ozone and chlorine monoxide concentrations were made with data collected on March 18, 2011. In both cases, high concentrations of the gas are dark, while low concentrations are light. The left image shows high ozone concentrations over most of the planet, but very low concentrations—the ozone hole—over the Arctic. The right image shows chlorine monoxide concentrations. In this case, the gas is concentrated over the Arctic in the region where the ozone hole developed.

The correlation between high chlorine monoxide and the ozone hole is no accident. Chlorine monoxide reacts with sunlight and ozone in a series of reactions that ultimately destroy ozone. What is unusual about the image is the concentration of chlorine monoxide. The gas forms naturally in the atmosphere only in very cold conditions where clouds or other particles are present in the atmosphere. Such conditions are extremely rare and are usually only found over Antarctica in the winter. In 2011, however, the Arctic also stayed cold long enough for ozone-destroying chlorine gases to build in the atmosphere.

For more information, visit, http://www.earthobservatory.nasa.gov/IOTD/view.php?id=60598

Tuesday, October 04, 2011

Saturn's Geyser Moon Enceladus Shows off for NASA's Cassini

Saturn's moon Enceladus was in full view on Oct 1, 2011NASA's Cassini spacecraft successfully completed its Oct. 1 flyby of Saturn's moon Enceladus and its jets of water vapor and ice. At its closest approach, the spacecraft flew approximately 62 miles (100 kilometers) above the moon's surface. The close approach was designed to give some of Cassini's instruments, including the ion and neutral mass spectrometer, the chance to "taste" the jets themselves.

At a higher vantage point during the encounter, Cassini's high-resolution camera captured pictures of the jets emanating from the moon's south polar region.

For more information about the Cassini-Huygens mission, visit http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov.

Monday, October 03, 2011

Dust over the Eastern Mediterranean Sea

Dust over the Eastern Mediterranean Sea

Dust from the Arabian Peninsula lingered over the eastern end of the Mediterranean Sea on September 29, 2011. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite took this picture the same day.

Dust plumes nearly surround the island of Cyprus, but leave skies over the center of the island largely clear. Dust extends far enough northward to reach the southern shores of Turkey. Thick dust also lingers over part of Syria.

Thick dust hovered over Jordan on September 28, and that is where the dust storm likely arose. Sand seas and dry salt lakes cover much of the country, supplying material for frequent dust storms.