NASA’s sun-observing Solar Dynamics Observatory (SDO) is currently in an eclipse season — a twice-yearly event in which Earth passes between SDO and the sun. In SDO images, you see a dark curve crossing the sun's face. And it's not the moon, and not a solar eclipse as we see from Earth. It's an eclipse of the sun by Earth, as seen from space. EarthSky's Deborah Byrd will show images of what SDO sees, and explain what the images show — and what they don’t show — and why perspective matters in ast