New iPhone App Monitors the Sun Live
A new iPhone application, or app, delivers a live global view of the sun along with alerts when the sun's activity flares up or when comets are discovered about to zoom around it.
A recent alert from the app notified users that a newfound comet was approaching the sun, for example. When the comet was destroyed, the app played a movie of its final hours.
"This is more than cool," said Dick Fisher, director of NASA's Heliophysics Division. "It's transformative. For the first time ever, we can monitor the sun as a living, breathing 3-dimensional sphere."
Realtime images used to construct the 3-D sphere are beamed to Earth by the Solar-Terrestrial Relations Observatory (STEREO), a pair of spacecraft with a combined view of 87 percent of the solar surface. STEREO-A is stationed over the western side of the sun, while STEREO-B is stationed over the east.
The sun has been at a low ebb of activity in the 11-year solar cycle, but that activity has been ramping up lately and is expected to peak in 2013. Big solar storms can knock out satellites and even cause power failures on Earth. STEREO is NASA's latest observatory designed to improve forecasting of solar storms.
"Using 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," said Lika Guhathakurta, STEREO program scientist.
Telescopes on STEREO monitor the sun in the extreme ultraviolet (EUV) portion of the electromagnetic spectrum. The images are therefore green. EUV observations reveal solar flares and new sunspots, plus "coronal holes," vast dark openings in the sun's atmosphere that spew streams of solar wind into the solar system.