Wednesday, April 28, 2010

IceBridge task at Halfway Point

On April 19, 2010, the IceBridge team flew underneath the clouds in difficult conditions to collect critical data for monitoring changes in sea ice in the Arctic Ocean. Credit: Michael Studinger

The 2010 Operation IceBridge mission to the Arctic is nearing its halfway point and wrapping up flights with NASA's DC-8 research airplane. In just over four weeks since leaving Palmdale, Calif., on March 21, scientists and crew have flown 14 successful missions over the Arctic Ocean and the Greenland Ice Sheet. They have been in the air for more than 120 hours and have flown a distance greater than 1.5 times around the world.

IceBridge project scientist Michael Studinger, from the Goddard Earth Science and Technology Center at the University of Maryland - Baltimore County, wrote from Thule, Greenland, to discuss some of the mission's accomplishments and critical moments, including one important flight that was almost thwarted by the Arctic weather.

Monday, April 26, 2010

NASA's New Eye on the Sun bring eye-catching First Images

NASA's recently launched Solar Dynamics Observatory, or SDO, is returning early images that confirm an unprecedented new capability for scientists to better understand our sun’s dynamic processes. These solar activities affect everything on Earth.

Some of the images from the spacecraft show never-before-seen detail of material streaming outward and away from sunspots. Others show extreme close-ups of activity on the sun’s surface. The spacecraft also has made the first high-resolution measurements of solar flares in a broad range of extreme ultraviolet wavelengths.

"These initial images show a dynamic sun that I had never seen in more than 40 years of solar research,” said Richard Fisher, director of the Heliophysics Division at NASA Headquarters in Washington. "SDO will change our understanding of the sun and its processes, which affect our lives and society. This mission will have a huge impact on science, similar to the impact of the Hubble Space Telescope on modern astrophysics.”

SDO will send 1.5 terabytes of data back to Earth each day, which is equivalent to a daily download of half a million songs onto an MP3 player. The observatory carries three state-of the-art instruments for conducting solar research.

The Helioseismic and Magnetic Imager maps solar magnetic fields and looks beneath the sun’s opaque surface. The experiment will decipher the physics of the sun’s activity, taking pictures in several very narrow bands of visible light. Scientists will be able to make ultrasound images of the sun and study active regions in a way similar to watching sand shift in a desert dune. The instrument’s principal investigator is Phil Scherrer of Stanford University. HMI was built by a collaboration of Stanford University and the Lockheed Martin Solar and Astrophysics Laboratory in Palo Alto, Calif.

The Atmospheric Imaging Assembly is a group of four telescopes designed to photograph the sun’s surface and atmosphere. The instrument covers 10 different wavelength bands, or colors, selected to reveal key aspects of solar activity. These types of images will show details never seen before by scientists. The principal investigator is Alan Title of the Lockheed Martin Solar and Astrophysics Laboratory, which built the instrument.

The Extreme Ultraviolet Variability Experiment measures fluctuations in the sun’s radiant emissions. These emissions have a direct and powerful effect on Earth’s upper atmosphere -- heating it, puffing it up, and breaking apart atoms and molecules. Researchers don’t know how fast the sun can vary at many of these wavelengths, so they expect to make discoveries about flare events. The principal investigator is Tom Woods of the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder. LASP built the instrument.

"These amazing images, which show our dynamic sun in a new level of detail, are only the beginning of SDO's contribution to our understanding of the sun," said SDO Project Scientist Dean Pesnell of Goddard.

SDO is the first mission of NASA's Living with a Star Program, or LWS, and the crown jewel in a fleet of NASA missions that study our sun and space environment. The goal of LWS is to develop the scientific understanding necessary to address those aspects of the connected sun-Earth system that directly affect our lives and society.

Wednesday, April 21, 2010

Students Send Balloons to the Stratosphere

How different does the world look from 100,000 feet in the air? How do cities and suburbs, fields and forests appear when viewed from a vantage point of nearly twenty miles above Earth's surface?

Through an innovative program at NASA's Glenn Research Center in Cleveland, local high school students have the opportunity to make these discoveries firsthand while learning practical math, science and engineering skills. Participants in the BalloonSAT Exploring Program launch a 6-foot diameter weather balloon, complete with experiments and cameras, into the space-like regions of Earth's upper atmosphere.

Exploring with Balloons

The Exploring Program is affiliated with the Boy Scouts of America. This program is designed to give high school students opportunities to experience different potential careers. Throughout the country, students in the Exploring Program learn from various professionals -- like firemen, police officers and medical workers -- about the skills necessary for these jobs. At Glenn, students explore what it's like to be a scientist or engineer in one of four Exploring Posts: Aeronautics, Computer, Human Space Exploration and BalloonSAT. Stephanie Brown-Houston, from the Glenn Educational Program, is the program manager for the Exploring Program → at Glenn.

The use of weather balloons as satellites (BalloonSAT) first began at Glenn a decade ago as a way of investigating solar cell calibration in space. A small payload which tracked the sun was suspended by a weather balloon and flown to gather data. The balloon served as an inexpensive high-altitude launch system.

The BalloonSAT Exploring Post 632 began in 2004. Dr. David Snyder, a physicist and electrical engineer in the Photovoltaic and Power Technologies branch of the Power & In-Space Propulsion division at Glenn, is the lead advisor for BalloonSAT Exploring Post.

"The overall goal is to give high school kids a chance to explore these professions," Snyder says. "It's about getting them interested in science and space and technology."

Learning by Doing

Each academic year, a group of 10 to 15 high school students join the BalloonSAT Exploring Post. These diverse students, from multiple high schools around the Cleveland area, work together to perform one or two launches every year. When the first launch occurs, it is more of a demonstration launch and takes place early in the program, in the fall. The second launch, which takes place in early spring, is coordinated and executed by the students and features the experiments they designed.

"BalloonSAT attempts to simulate a satellite mission," Snyder says. "We give students the chance to design experiments and fly them with a flight program, and get results."

The students work all year to research, develop, design and fabricate experiments that will be flown when they launch their balloon. In the seven missions that BalloonSAT has flown, dozens of student-designed experiments have been launched 100,000 feet in the air.

Previous experiments have included:
* Exposure experiments with rubber bands, seeds and mold
* Light and temperature sensors
* Aerogel particle capture
* Cosmic ray detection
* Geiger counters
* Electronic compass correlation
* Carbon Dioxide/Ozone detectors
* Solar cell measurements
* Latex balloon expansion
* Yeast growth and carbon dioxide generation

This year's launch, which is schedule for April 24, includes a variety of experiments such as:

* 3-D photography
* Video image transmission
* Chemical hand warmer testing
* Electric field disturbances
* Glass fragility during flight
* Wood glue exposure
* Humidity measurements

The students spend the year preparing for the launch; the multi-faceted project teaches the students numerous skills.

Monday, April 19, 2010

Helicopter Helps Test Radar for 2012 Mars Landing

This spring, engineers are testing a radar system that will serve during the next landing on Mars.

Recent tests included some near Lancaster, Calif., against a backdrop of blooming California poppy fields. In those tests, a helicopter carried an engineering test model of the landing radar for NASA's Mars Science Laboratory on prescribed descent paths. The descents at different angles and from different heights simulated paths associated with specific candidate sites for the mission.

The Mars Science Laboratory mission, managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA, is in its assembly and testing phase, in advance of a launch in autumn 2011 and delivery of a rover named Curiosity to Mars in summer 2012.

During the final stage of the spacecraft's arrival at Mars in 2012, a rocket-powered descent stage will lower the rover on a tether directly to the ground. This rover is too big for the airbag-cushioned landing method used by NASA's Mars Pathfinder mission in 1997 and Mars Exploration Rover landings in 2004.

At Mars, a radar on the descent stage will track the spacecraft's decreasing distance from the surface. Additional helicopter-flown testing of the mission's radar system will include checks of whether the suspended rover might confuse the radar about the speed of descent toward the ground.

Monday, April 12, 2010

NASA-Funded Research Suggests Venus is Geologically Alive

For the first time, scientists have detected clear signs of recent lava flows on the surface of Venus.

The observations reveal that volcanoes on Venus appeared to erupt between a few hundred years to 2.5 million years ago. This suggests the planet may still be geologically active, making Venus one of the few worlds in our solar system that has been volcanically active within the last 3 million years.

The evidence comes from the European Space Agency's Venus Express mission, which has been in orbit around the planet since April 2006. The science results were laid over topographic data from NASA's Magellan spacecraft. Magellan radar-mapped 98 percent of the surface and collected high-resolution gravity data while orbiting Venus from 1990 to 1994.

Scientists see compositional differences compared to the surrounding landscape in three volcanic regions. Relatively young lava flows have been identified by the way they emit infrared radiation. These observations suggest Venus is still capable of volcanic eruptions. The findings appear in the April 8 edition of the journal Science.

These video stills show the volcanic peak Idunn Mons (at 46 degrees south latitude, 214.5 degrees east longitude) in the Imdr Regio area of Venus
"The geological history of Venus has long been a mystery," said Sue Smrekar, a scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif., and lead author of the paper describing the work. "Previous spacecraft gave us hints of volcanic activity, but we didn't know how long ago that occurred. Now we have strong evidence right at the surface for recent eruptions."

The volcanic provinces, or hotspots, on which Smrekar and her team focused are geologically similar to Hawaii. Scientists previously detected plumes of hot rising material deep under Venus' surface. Those plumes are thought to have produced significant volcanic eruptions. Other data from the planet suggest that volatile gases commonly spewed from volcanoes were breaking down in its atmosphere. The rate of volcanism will help scientists determine how the interior of the planet works and how gases emitted during eruptions affect climate.

Something is smoothing Venus' surface, because the planet has only about 1,000 craters, a relatively small amount compared to other bodies in our solar system. Scientists think it may be the result of volcanic activity and want to know if it happens quickly or slowly. The Venus Express results suggest a gradual sequence of smaller volcanic eruptions as opposed to a cataclysmic volcanic episode that resurfaces the entire planet with lava.

Smrekar and her team also discovered that several volcanic features in the regions they studied show evidence of minerals found in recent lava flows. These mineral processes correspond to the youngest volcanic flows in each region, giving scientists additional support for the idea they formed during recent volcanic activity. On Earth, lava flows react rapidly with oxygen and other elements in the atmosphere when they erupt to the surface. On Venus, the process is similar, although it is more intense and changes the outer layer more substantially.

Scientists call Venus Earth's sister planet because of similarities in size, mass, density and volume. Scientists deduce that both planets shared a common origin, forming at the same time about 4.5 billion years ago. Venus also is the planet on which the runaway greenhouse effect was discovered. The planet is cloaked in a much less friendly atmosphere than that found on Earth. It is composed chiefly of carbon dioxide, which generates a surface temperature hot enough to melt lead, and a surface pressure 90 times greater than that on Earth.

The small group of worlds in our solar system known to be volcanically active today includes Earth and Jupiter's moon Io. Crater counts on Mars also have suggested recent lava flows. Scientists are studying evidence of another kind of active volcanism that involves ice-spewing volcanoes on other moons in our solar sys

Wednesday, April 07, 2010

Arctic 2010 Sea Ice Maximum, Visualized

NASA - Sea ice coverage over the Arctic Ocean oscillates over the course of a year, growing through winter and reaching a maximum extent by February or March. This year, Arctic sea ice grew to levels beyond those measured in recent years but slightly below average when compared to the 30-year satellite record.

Friday, April 02, 2010

Cassini Doubleheader- Flying By Titan and Dione

In a special double flyby early next week, NASA's Cassini spacecraft will visit Saturn's moons Titan and Dione within a period of about a day and a half, with no maneuvers in between. A fortuitous cosmic alignment allows Cassini to attempt this doubleheader, and the interest in swinging by Dione influenced the design of its extended mission.

The Titan flyby, planned for Monday, April 5, will take Cassini to within about 7,500 kilometers (4,700 miles) of the moon's surface. The distance is relatively long as far as encounters go, but it works to the advantage of Cassini's imaging science subsystem. Cassini's cameras will be able to stare at Titan's haze-shrouded surface for a longer time and capture high-resolution pictures of the Belet and Senkyo areas, dark regions around the equator that ripple with sand dunes.

In the early morning of Wednesday, April 7 in UTC time zones, which is around 9 p.m. on Tuesday, April 6 in California, Cassini will make its closest approach to the medium-sized icy moon Dione. Cassini will plunge to within about 500 kilometers (300 miles) of Dione's surface.

This is only Cassini's second close encounter with Dione. The first flyby in October 2005, and findings from the Voyager spacecraft in the 1990s, hinted that the moon could be sending out a wisp of charged particles into the magnetic field around Saturn and potentially exhaling a diffuse plume that contributes material to one of the planet's rings. Like Enceladus, Saturn's more famous moon with a plume, Dione features bright, fresh fractures. But if there were a plume on Dione, it would certainly be subtler and produce less material.

Cassini plans to use its magnetometer and fields and particles instruments to see if it can find evidence of activity at Dione. Thermal mapping by the composite infrared spectrometer will also help in that search. In addition, the visual and infrared mapping spectrometer will examine dark material found on Dione. Scientists would like to understand the source of this dark material.

Cassini has made three previous double flybys and another two are planned in the years ahead. The mission is nearing the end of its first extension, known as the Equinox mission. It will begin its second mission extension, known as the Solstice Mission, in October 2010.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate in Washington. The Cassini orbiter was designed, developed and assembled at JPL.