First 3-D Images of the Sun

First 3-D Images of the Sun



   
April 2007 -   Two NASA 
spacecraft orbiting the Sun together have recorded the first 
three dimenvironment newsional images of the Sun and beamed them back to 
Earth. For the first time, scientists will be able to see 
structures in the Sun's atmosphere in three dimenvironment newsions, 
helping them to better predict space weather that could 
disrupt Earth's satellites and power grids. 
NASA's twin Solar Terrestrial Relations Observatory, STEREO, 
spacecraft were launched together October 25, 2006 from Cape 
Canaveral, Florida. 
On January 21 they completed a series of complex maneuvers, 
including flying by the Moon, to position the spacecraft in 
two separate orbits about the Sun. 
Fitted with suites of telescopes, they are now orbiting the 
Sun, one slightly ahead of Earth and one slightly behind. 
Just as the slight offset between a person's eyes provides 
depth perception, the separation of these spacecraft allows 
NASA to create 3-D images of the Sun. 
The new view will help scientists to understand solar physics 
and improve space weather forecasting. 
One of the first 3-D images of the Sun. This is not a true 
color image. To see the Sun in 3-D as STEREO sees it, special 
3-D glasses are needed. 
"In the solar atmosphere, there are no clues to help us judge 
distance. Everything appears flat in the 2-D plane of the sky. 
Having a stereo perspective just makes it so much easier," 
said Dr. Russell Howard of the Naval Research Laboratory, 
Washington. Howard is the principal investigator for the suite 
of telescopes on the spacecraft known as the Sun Earth 
Connection Coronal and Heliospheric Investigation project. 
"With STEREO's 3-D imagery, we'll be able to discern where 
matter and energy flows in the solar atmosphere much more 
precisely than with the 2-D views available before," said 
Howard. "This will really help us understand the complex 
physics going on." 
Violent solar weather originates in the Sun's atmosphere, or 
corona, and can disrupt satellites, radio communication, power 
grids and the Global Positioning System on Earth. 
The corona resembles wispy smoke plumes, which flow outward 
along the Sun's tangled magnetic fields, making it difficult 
for scientists on Earth to tell which structures are in front 
and which are behind. 
Of particular concern is a destructive type of solar eruption 
called a coronal mass ejection, CME. CMEs are eruptions of 
electrically charged gas, called plasma, from the Sun's 
atmosphere. NASA says a CME cloud can contain billions of tons 
of plasma and move at a million miles per hour. A close up of
 loops in a magnetic active region of the Sun. 
These loops, observed by STEREO's telescope, are at a million 
degrees Celsius. This powerful active region, AR903, observed 
here on December 4, 2006, produced a series of intense flares 
over the next few days. 
CME clouds are laced with magnetic fields and can smash into 
Earth's magnetic field, causing magnetic storms that can 
overload power line equipment and radiation storms that 
disrupt satellites. 
Satellite and utility operators can take precautions to 
minimize CME damage, but they need an accurate forecast of 
when the CME will arrive. To do this, forecasters need to know 
the location of the front of the CME cloud. 
Data from the STEREO spacecraft will allow scientists to 
accurately locate the CME cloud fronts. 
"Knowing where the front of the CME cloud is will improve 
estimates of the arrival time from within a day or so to just 
a few hours," said Howard. "STEREO also will help forecasters 
estimate how severe the resulting magnetic storm will be." 
"In addition to the STEREO perspective of solar features, 
STEREO for the first time will allow imaging of the solar 
disturbances the entire way from the Sun to the Earth," said 
Dr. Madhulika Guhathakurta, STEREO program scientist at NASA 
Headquarters in Washington, DC. 
Presently, scientists are only able to model this region in 
the dark, from only one picture of solar disturbances leaving 
the Sun and reaching only a fraction of the Sun-Earth 
distance. 
As of today, five museums and planetariums across the United 
States are showing NASA's 3-D images of the Sun. They are the 
American Museum of Natural History's Hayden Planetarium in New 
York City through April 27; the Christa McAuliffe Planetarium 
in Concord, New Hampshire; the Maryland Science Center in 
Baltimore; the Adler Planetarium in Chicago; and the Denver 
Museum of Nature & Science. Check with each facility for the 
show's final date. 
STEREO's first 3-D images are being provided by NASA's Jet 
Propulsion Laboratory in Pasadena, California. 
STEREO is the third mission in NASA's Solar Terrestrial Probes 
program within NASA's Science Mission Directorate, Washington.
 The Goddard Science and Exploration Directorate manages the 
mission, instruments, and science center. 
The Johns Hopkins University Applied Physics Laboratory, 
Laurel, Maryland, designed and built the spacecraft and is 
responsible for mission operations. 
The STEREO imaging and particle detecting instruments were 
designed and built by scientific institutions in the United 
States, the UK, France, Germany, Belgium, Netherlands, and 
Switzerland. 
For sources of 3-D glasses, visit the NASA website at: 
http://www.nasa.gov/mission_pages/stereo/sun/3D_Glasses.html 

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