NARRATOR: As any space scientist will tell you, we live in a golden age of solar research. Thanks to a series of new telescopes launched in the last two decades, we now have more – and better – ways to look at the Sun than ever before. The list of missions responsible for this new wave of solar research is long.
Here’s a quick introduction to three key ones that you’ll be using in our Sun Lab.
The first is the SOHO satellite, which launched in December, 1995. A collaboration between NASA and the European Space Agency, SOHO bristles with a dozen telescopes. With each one tuned to a distinct part of the electromagnetic spectrum, SOHO brought new regions of the Sun into focus for the first time.
For example, one of its telescopes uses relatively long wavelengths coming from the surface to indirectly model the Sun’s core.
But SOHO is probably best known for revolutionizing our understanding of space weather. Within its first year, SOHO scientists had learned how to track Coronal Mass Ejections and figure out which ones might be headed our way. Here, SOHO captures a period in 2011 when the Sun produced six of these storms in a single day.
The next groundbreaking mission, called STEREO, consists of two satellites. Since its launch in 2006, Stereo A has raced ahead of Earth in its solar orbit, while Stereo B has fallen further behind. As the telescopes have drifted farther apart, they’ve provided increasingly complementary views of the Sun, each day bringing more of it into view.
This led to a dramatic moment in February, 2011. For the first time in human history, we had a view of the entire Sun, not just the part facing Earth.
Because the Sun takes 27 days to rotate once, there used to be plenty of time for solar activity to develop without us noticing. Now, we can see active regions as soon as they form, leading to much better forecasting.
But the newest and most powerful telescope ever pointed at the Sun is the Solar Dynamics Observatory, or SDO for short. Think of it like SOHO on steroids. From its position near Earth, SDO also looks at many different wavelengths of solar radiation. But more than once per second, it delivers images ten times more detailed than HDTV.
Some estimates say this digital fire hose will transmit 50 times more science data than any mission in NASA history.
In our Sun Lab, you’ll see images from two of SDO’s three main instruments.
The first is AIA, a battery of four telescopes that can look at ten different wavelengths of light. These range from the Sun’s surface up to the highest reaches of the super-hot corona, the key to modeling space weather.
The second SDO instrument featured in the lab is called HMI. The “H” stands for “helioseismology,” because it uses sound waves moving through the surface to model changing magnetic fields generated in the convective zone below. By mapping these complex fields across the entire Sun, HMI helps scientists more quickly spot the conditions that can lead to solar storms.
Of course, these are not the only solar missions, and there are more in the planning stages – including one that will fly right into the Sun’s corona.
So keep looking – not at the Sun itself, but at the images coming from our solar telescopes. Not only is it safer for your eyes, but you’ll see a lot more.