Solar Dynamics Observatory views sun for first time
BY STEPHEN CLARK
Posted: April 21, 2010
Nearly 10 weeks after launching on a cold Florida morning, the Solar Dynamics Observatory has captured the most detailed images of the scorching surface of the sun.
Scientists released the pictures in a press conference at the Newseum in Washington, D.C.
The results are just the first samples from the $848 million mission, which will beam up to 150 million bits of data to Earth every second during its five-year lifetime.
"We're already learning new things from the images that we're seeing from our instruments," said Dean Pesnell, SDO's project scientist at the Goddard Space Flight Center.
SDO's three instruments starting taking data in late March after the satellite reached an orbital perch 22,300 miles above Earth, where it hovers in geosynchronous orbit over a ground station at White Sands, N.M.
The satellite launched Feb. 11 on an Atlas 5 rocket. See our coverage of SDO's launch here.
"The spacecraft is one of the most flawless operating ones I've ever seen," said Richard Fisher, director of NASA's heliophysics division. "The first images are now in hand, and these are truly spectacular and they show the details of our sun that have not been available to us before."
Scientists are calling the mission the Hubble Space Telescope of heliophysics, implying SDO will rewrite textbooks and revamp theories on solar activity.
"The impact of this observatory on the physics of stars, solar physics, solar-terrestrial research and the field of space weather will be truly revolutionary," Fisher said.
Breathtaking imagery from Atmospheric Imaging Assembly assembled shows surface eruptions emitting strings of plasma into the solar atmosphere and sending powerful shock waves across the sun.
"From this, we can begin, for the first time, to decode how this energy is released into the outer atmosphere," said Alan Title, the AIA instrument principal investigator at the Lockheed Martin Solar and Astrophysics Laboratory.
AIA features four telescopes designed to be sensitive at different temperatures, giving scientists information on how heat is transferred across the sun.
Another instrument, the Helioseismic and Magnetic Imager, will probe the sun's interior to track developing solar storms from their genesis deep inside the sun to the violent eruptions at the surface.
Early results from HMI show rapid motion of sound waves at the surface, which resembles raindrops striking a pond, said Phil Scherrer, the sensor's chief scientist at Stanford University.
The EVE ultraviolt instrument studies space weather, the link between the sun and the Earth that can affect communications and navigation signals.
"Our first image from EVE doesn't look anything like it should," Pesnell said.
While the satellite's other two instruments study the formation of storms on the sun, EVE directly measures how they impact Earth.
"These new measurements will be used by NASA, NOAA and the Air Force to more precisely predict each solar flare and how it will change our ionosphere," said Tom Woods, the EVE principal investigator at the University of Colorado. "[Along] with modeling efforts to understand the ionosphere, they will also be able to make better predictions of how it will disrupt communications and navigation."