NASA SDO: Sun Monitoring Satellite captures 100 millionth image

The Atmospheric Imaging Assembly on NASA's Solar Dynamics Observatory captured its 100 millionth image of the sun on Jan. 19, 2015. 

The dark areas at the bottom and the top of the image are coronal holes, areas of less dense gas, where solar material has flowed away from the sun. 

Credit: NASA/SDO/AIA/LMSAL

On Jan. 19, 2015, at 12:49 p.m. EST, an instrument on NASA's Solar Dynamics Observatory captured its 100 millionth image of the sun.

The instrument is the Atmospheric Imaging Assembly (AIA), which uses four telescopes working parallel to gather eight images of the sun, cycling through 10 different wavelengths -- every 12 seconds.

The Atmospheric Imaging Assembly (AIA) images the solar atmosphere in multiple wavelengths to link changes in the surface to interior changes. 

Data includes images of the Sun in 10 wavelengths every 10 seconds. 

Credit: NASA SDO, Lockheed Martin Solar Astrophysics Laboratory

The Helioseismic and Magnetic Imager extends the capabilities of the SOHO/MDI instrument with continual full-disk coverage at higher spatial resolution and new vector magnetogram capabilities.

Credit: NASA SDO, Lockheed Martin Solar Astrophysics Laboratory

Between the AIA and two other instruments on board, the Helioseismic Magnetic Imager (HMI) and the Extreme Ultraviolet Variability Experiment (EVE), SDO sends down a whopping 1.5 terabytes of data a day.

The Extreme Ultraviolet Variability Experiment measures the solar extreme-ultraviolet (EUV) irradiance with unprecedented spectral resolution, temporal cadence, and precision. 

EVE measures the solar extreme ultraviolet (EUV) spectral irradiance to understand variations on the timescales which influence Earth's climate and near-Earth space.

Credit: NASA SDO, Lockheed Martin Solar Astrophysics Laboratory

AIA is responsible for about half of that. Every day it provides 57,600 detailed images of the sun that show the dance of how solar material sways and sometimes erupts in the solar atmosphere, the corona.

In the almost five years since its launch on Feb. 11, 2010, SDO has provided images of the sun to help scientists better understand how the roiling corona gets to temperatures some 1000 times hotter than the sun's surface, what causes giant eruptions such as solar flares, and why the sun's magnetic fields are constantly on the move.

NASA SDO: Bright points in Sun's atmosphere mark patterns deep in its interior

Brightpoints in the sun's atmosphere, left, correspond to magnetic parcels on the sun's surface, seen in the processed data on the right. 

Green spots show smaller parcels, red and yellow much bigger ones. 

Credit: NASA/SDO

Like a balloon bobbing along in the air while tied to a child's hand, a tracer has been found in the sun's atmosphere to help track the flow of material coursing underneath the sun's surface.

New research that uses data from NASA's Solar Dynamics Observatory (SDO), to track bright points in the solar atmosphere and magnetic signatures on the sun's surface offers a way to probe the star's depths faster than ever before.

The technique opens the door for near real-time mapping of the sun's roiling interior – movement that affects a wide range of events on the sun from its 22-year sunspot cycle to its frequent bursts of X-ray light called solar flares.

"There are all sorts of things lurking below the surface," said Scott McIntosh, first author of a paper on these results in the April 1, 2014, issue of the Astrophysical Journal Letters.

"And we've found a marker for this deep rooted activity. This is kind of a gateway to the interior, and we don't need months of data to get there."

One of the most common ways to probe the sun's interior is through a technique called helioseismology in which scientists track the time it takes for waves – not unlike seismic waves on Earth—to travel from one side of the sun to the other.

From helioseismology solar scientists have some sense of what's happening inside the sun, which they believe to be made up of granules and super-granules of moving solar material.

The material is constantly overturning like boiling water in a pot, but on a much grander scale: A granule is approximately the distance from Los Angeles to New York City; a super-granule is about twice the diameter of Earth.

SDO contains three instruments; Helioseismic and Magnetic Imager (HMI), Atmospheric Imaging Assembly (AIA), and Extreme Ultraviolet Variablity Experiment (EVE) -- for observations leading to a more complete understanding of the solar dynamics that drive variability in the Earth's environment. 

Credit: NASA/Goddard Space Flight Center

Instead of tracking seismic waves, the new research probes the solar interior using the Helioseismic Magnetic Imager (HMI) on SDO, which can map the dynamic magnetic fields that thread through and around the sun.

Since 2010, McIntosh has tracked the size of different magnetically-balanced areas on the sun, that is, areas where there are an even number of magnetic fields pointing down in toward the sun as pointing out.

Think of it like looking down at a city from above with a technology that observed people, but not walls, and recording areas that have an even number of men and women.

Even without seeing the buildings, you'd naturally get a sense for the size of rooms, houses, buildings, and whole city blocks – the structures in which people naturally group.

More Information: 'Identifying Potential Markers of the Sun's Giant Convective Scale' Astrophysical Journal April 2014: Authors: Scott W. McIntosh, Xin Wang, Robert J. Leamon, and Philip H. Scherrer: doi:10.1088/2041-8205/784/2/L32