Last week, space fans everywhere sat on the edge of their seats, anxiously awaiting the first images from NASA’s Solar Dynamics Observatory, or SDO. And boy, were we treated to a feast! The first-light images were not only stunning and exquisitely detailed, but also contained a wealth of scientific information that’s sure to keep solar physicists busy for some time.
During the press conference, the question was asked, “Why should the public care about SDO?” My immediate response (spoken to my laptop screen, confusing my office mates) was, “Because it’s awesome!” Of course, I’m a bit biased because I got to watch SDO liftoff from Kennedy Space Center back in February.
The truth is, SDO will have a direct influence on our lives, as the sun has a direct influence on the planet that we inhabit. SDO is the first of NASA’s “Living with a Star” program, treating the sun as a variable star that has a direct effect on us. We know that solar activity can wreak havoc on our technology-driven society, but we need a deeper understanding of the sun in order to predict activity.
Our planet is nestled in the outer atmosphere of the sun. When it is most active, the sun sends out storms of highly energetic particles in coronal mass ejections, or CMEs. When one of these bursts is pointed at earth, the charged particles interact with the Earth’s protective magnetosphere. Satellites and astronauts in orbit aren’t as well protected as we are down on the surface and are vulnerable to equipment failures or health hazards.
Solar flares, a phenomenon related to CMEs, emit bright light all across the electromagnetic spectrum, from radio all the way to -ray and gamma ray. These can change the structure of the Earth’s charged outer atmosphere, the ionosphere, diminishing the accuracy of sensitive GPS measurements, interfering with communications, and making it a bad day for low frequency radio astronomy. (Yes, there are a few of us who care about that!)
Even if you don’t mind the occasional communication or navigation interruption, you have to watch out for large-scale power outages. Geomagnetic storms can directly affect transformers, causing them to fail, and increasingly interconnected power grids will only make the problem worse.
So what can we do? We certainly can’t control the sun, but we can gain a deeper understanding of the sun and better predict these events. Then we can brace our power grids, send the astronauts to a shielded compartment, power down vulnerable satellites, and patiently wait for the storm to subside. SDO’s super high-resolution images and spectra, magnetic field mapping, and variability monitoring are sure to give us an edge with our life-giving, but fickle, star.
Image: A view of the multimillion-degree plasma of the sun (NASA/SDO)