Sunday, February 28, 2010

NASA Unveils New Space-Weather Science Tool

When NASA’s satellite operators need accurate, real-time space-weather information, they turn to the Community Coordinated Modeling Center (CCMC) of the Space Weather Laboratory at NASA's Goddard Space Flight Center in Greenbelt, Md. The CCMC’s newest and most advanced space-weather science tool is the Integrated Space Weather Analysis (iSWA) system.

The iSWA is a robust, integrated system provides information about space weather conditions past, present, and future and, unlike many other programs currently in use, has an interface that the user can customize to suit a unique set of data requirements.

Animation illustrating an artist's concept of Coronal Mass Ejection (CME) cannibalism

"The iSWA space-weather data analysis system offers a unique level of customization and flexibility to maintain, modify, and add new tools and data products as they become available," says Marlo Maddox, iSWA system chief developer at NASA Goddard.

iSWA draws together information about conditions from the sun to the boundary of the sun’s influence, known as the heliosphere. The iSWA systems digests information from spacecraft including the National Oceanic and Atmospheric Administration’s (NOAA) Geostationary Operational Environmental Satellites (GOES), NASA’s Solar Terrestrial Relations Observatory (STEREO), the joint European Space Agency and NASA mission Solar and Heliospheric Observatory (SOHO), and NASA's Advanced Composition Explorer (ACE).

Citizen scientists and science enthusiasts can also use the data, models, and tools of the iSWA system. Similar to the way in which armchair astronomers have used SOHO data to discover comets, enthusiasts will find the iSWA system a wonderful resource for increasing their familiarity with the concept of space weather.

Monday, February 22, 2010

3D Sun for the iPhone

Imagine holding the entire sun in the palm of your hand. Now you can. A new iPhone app developed by NASA-supported programmers delivers a live global view of the sun directly to your cell phone. Users can fly around the star, zoom in on active regions, and monitor solar activity.

"This is more than cool," says Dick Fisher, director of NASA's Heliophysics Division in Washington DC. "It's transformative. For the first time ever, we can monitor the sun as a living, breathing 3-dimensional sphere."

The name of the app is "3D Sun" and it may be downloaded free of charge at Apple's app store. Just enter "3D Sun" in the Store's search box or visit http://3dsun.org for a direct link.

Realtime images used to construct the 3-dimensional sphere are beamed to Earth by the Solar-Terrestrial Relations Observatory (STEREO), a pair of spacecraft with a combined view of 87% of the solar surface. STEREO-A is stationed over the western side of the sun, while STEREO-B is stationed over the east. Together, they rarely miss a thing.

Screen capture of 3D Sun on the iPhone

Telescopes onboard the two spacecraft monitor the sun in the extreme ultraviolet (EUV) portion of the electromagnetic spectrum. "That's why the 3D sun looks false-color green," explains Lika Guhathakurta, STEREO program scientist at NASA Headquarters. "These are not white-light images."

That's okay because EUV is where the action is. Solar flares and new sunspots shine brightly at these wavelengths. EUV images also reveal "coronal holes," vast dark openings in the sun's atmosphere that spew streams of solar wind into the solar system. Solar wind streams that hit Earth can spark intense displays of Northern Lights.

"With this app, you can spin the sun, zoom in on sunspots, inspect coronal holes--and when a solar flare erupts, your phone plays a little jingle to alert you!" says Guhathakurta.

Tuesday, February 16, 2010

Cassini Set to Do Retinal Scan of Saturnian Eyeball

Saturn Moon MimarOn Feb. 13, 2010, NASA's Cassini spacecraft will make its closest examination yet of Mimas, an eyeball-shaped moon of Saturn that has also been likened to the Death Star of "Star Wars." The spacecraft will be returning the highest-resolution images yet of this battered satellite.

Mimas bears the mark of a violent, giant impact from the past - the 140-kilometer-wide (88-mile-wide) Herschel Crater - and scientists hope the encounter will help them explain why the moon was not blown to smithereens when the impact happened. They will also be trying to count smaller dings inside the basin of Herschel Crater so they can better estimate its age.

In addition, Cassini's composite infrared spectrometer will be working to determine the thermal signature of the moon, and other instruments will be making measurements to learn more about the surface composition.

The Mimas flyby involves a significant amount of skill because the spacecraft will be passing through a dusty region to get there. Mission managers have planned for the Cassini spacecraft to lead with its high-gain antenna to provide a barrier of protection. At closest approach, the spacecraft will be flying about 9,500 kilometers (5,900 miles) above the moon. Cassini will start taking images and measurements shortly after closest approach.