Solar Dynamics Observatory unveils "first light" movies
The Solar Dynamics Observatory launched into Earth orbit on February 11, 2010 and is now returning data on the Sun at a truly unimaginable rate: 1.5 Terabytes per day. A large part of that data comes in the form of full-disk images of the Sun captured in 10 different wavelength bands (one visible, the rest ultraviolet) at a resolution of 725 kilometers per pixel every 10 seconds. We've had solar observing spacecraft before but never had such a detailed view of the dynamic processes that operate on the Sun. Here's a few of the movies they showed at today's press briefing.
First, here's a solar prominence erupting. Look at the way it twists. Principal Investigator Dean Pesnell said he showed this to one theorist and said it's already disproven one theory about how these things form and evolve.
Next, here's a coronal mass ejection erupting in our direction as seen in numerous wavelengths. Alan Title remarked that the wavefront is moving at half a million miles an hour; video frames are spaced 20 seconds apart in time. This is a halo coronal mass ejection, which impacts Earth.
My favorite perspective on the new capability to observe our Sun that SDO affords us came from NASA SDO program scientist Madhulika Guhathakurta. "Even hardcore physicists like ourselves are struck with awe. You just want to know how these are created, how they are going to affect us, and how we can predict them. We can see events unfolding before our eyes. Theories are being discarded. We live in the outer atmosphere of this restless, magnetic star. It produces harmful particles and radiation that can alter life's evolution."
Guhathakurta went on to show this interesting simulation that explains how a coronal mass ejection can produce aurorae. She said "this is what happens when a coronal mass ejection, a cloud of plasma that is big enough to swallow the Earth, impinges on Earth's magnetosphere. Luckily enough, we have this magnetic shield; most of these particles are ejected. Once in a while, field lines of the Sun and field lines of the magnetosphere are aligned just right, and that's when solar particles penetrate the magnetosphere to make the aurora."