This full-disk multiwavelength extreme ultraviolet image of the sun was taken by the new Solar Dynamics Observatory on March 30. False colors trace different gas temperatures. Reds are relatively cool (about 110,000 degrees Fahrenheit); blues and greens are hotter (greater than 1.8 million degrees F).
By Andrea Thompson
updated 5:24 p.m. MT, Wed., April 21, 2010The first images of the sun beamed home from NASA's newest solar observatory have wowed mission scientists with their extraordinary detail and unexpected findings.
NASA on Wednesday released the first new images from the Solar Dynamics Observatory, a probe launched on Feb. 11 to peer deep into the layers of the sun, monitor solar storms and investigate the mysteries of the sun's inner workings.
"The spacecraft and the instruments are working very well," said Richard Fisher, director of the Heliophysics Division at NASA Headquarters in Washington. "What we've seen is truly, in my view, spectacular."
The Solar Dynamics Observatory, or SDO, carries three instruments that constantly stare at the sun, generating images that have a resolution 10 times better than high-definition television.
"I believe this is going to be a revolutionary view" of the sun, said Fisher, who likened the new observatory's impact to that of the Hubble Space Telescope.
SDO will be revolutionary to the study of the sun "in the same way Hubble was revolutionary for astrophysics," he told Space.com.
The young solar observatory will also be generating an astounding amount of data.
It will stream the equivalent of half a million songs per day down to a ground station from its geosynchronous orbit. That's about 150 million bits of data per second, 24 hours a day, seven days a week — almost 50 times more science data than any other mission in NASA's history.
Monitoring solar flares, storms
The simultaneous monitoring of several wavelengths of the sun's light, coupled with the more rapid pace of observations, will give scientists an unprecedentedly detailed view of the features present on the sun. It will also help monitor the solar flares and storms that can impact Earth, as well as shed light on the influence of the sun's magnetic field on the processes that take place within the sun.
"The nice thing about SDO is that we have all of the sun all of the time," said Philip H. Scherrer the principal investigator for SDO's Helioseismic and Magnetic Imager instrument at Stanford University. Already observations of solar features and their evolution is showing that "the magnetic field is really much more dominant than we thought," Fisher said.
t's also very dynamic: "That magnetic field is never the same twice, it is always changing," said Dean Pesnell, SDO project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md.
And though the spacecraft is still in its commissioning phase — meaning all of the instruments are being properly calibrated and the probe is entering its final orbit — it has taken images that are already making unexpected revelations.
One particularly interesting observation, Fisher said, shows the evolution of an active region of the sun, also known as a sunspot. The dark spots on the sun's surface are connected to intense magnetic activity. SDO caught this sunspot in decline that didn't look quite how scientists expected it to.
"It's a little bit baffling about what happened," Fisher said.
Tiny changes, huge impact
SDO observed that tiny changes in the magnetic field due to the decline of the sunspot "have a huge impact on the upper solar atmosphere," Fisher said, likening that to a situation on Earth where a lightning bolt in Indiana would cause a hurricane on the East Coast.
The sunspot is associated with a blast of solar material out into space known as a coronal mass ejection, or CME. SDO was able to see the sunspot associated with this CME as well as the waves rippling across the sun's surface associated with it and the flare that caused it.
The CME ejected as much material as is contained in the entire Mississippi River at a speed of about a million miles per hour; the material was accelerated up to that speed in just one second, said Alan Title, the principal investigator of SDO's Atmospheric Imaging Assembly instrument at Lockheed Martin Solar and Astrophysics Laboratory in Palo Alto, Calif.
That SDO is already stumping scientists with its findings even though it's not yet in full observing mode (which will happen sometime next month) shows what a useful spacecraft it is, Fisher said.
"The hallmark of a successful science experiment [is] that you don't understand what you've gotten back," he said.
Helping with predictions
Such solar events aren't just interesting to scientists — they can have a major impact on the Earth by knocking out communication systems, GPS satellites and even electrical grids. Scientists hope that SDO will allow them to make better predictions on when solar flares and CMEs might erupt in Earth's direction.
"The more we know about these flares, the better we'll be able to be proactive instead of reactive" to space weather, said Tom Woods the principal investigator of the Extreme Ultraviolet Variability Experiment instrument at the University of Colorado in Boulder.
And by allowing scientists to better understand the sun, SDO will also shed light on the workings of other stars.
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