Monday Astronomy Picture Ponderings 5/23/2022

6 min readMay 23, 2022

Our deceptively active star

A close-up gif of a solar “tsunami” of a solar flare “bursting” and rippling across the solar surface, starting from the top left of the picture of the Sun. The image is in black and white with the solar flare appearing brighter than the rest of the sun as the released energy is hotter than the rest of the Sun’s surface. — **A Large Tsunami Shock Wave on the Sun**, from NASA APOD 5/22/2022, **Image Credit:** NSO/AURA/NSF and USAF Research Laboratory

Welcome back to the Monday Astronomy Picture Ponderings (MAPPs) series where every Monday I pick one of NASA’s Astronomy Picture of the Day (APOD) entries from the past seven days to focus on in some way.

The Sun is a fairly constant feature in our lives. Even in the areas of the world where you won’t see the Sun for 6 months of the year, it won’t set for the other 6 months. It is something we all expect to see in the sky on a fairly regular basis. Even as children, we can easily add a sun to a picture we are creating. It’s a simple solid yellow circle (or semi-circle in the corner). It’s how we see the Sun every day, to a degree.

We all know what to draw when someone instructs us to draw a sun in a picture. But is that really what we see, is that really how the Sun is?

If we really think about it, we know that the light we see from the Sun is white as opposed to yellow. We’ve discussed before how white light contains all the visible colors, but our eyes are not good enough to distinguish each individual color.

So, we know that the Sun is actually pushing out light from all across the visible spectrum, not just white or yellow. We also know that in actuality, our Sun is a yellow star, making it not the hottest or brightest star, nor the coolest or dimmest star, but right in the middle. Red stars are actually the coolest stars with blue-white stars being the hottest (think of a welding torch or a bunsen burner).

But is that all the Sun is? A stable, yellow ball of gas?

We are constantly studying our Sun to better understand its relationship with Earth and the rest of the solar system as well as the evolution of stars in general. And so despite the fact that our eyes often see this when looking at the Sun:

Stars are actually extremely active and even volatile. Stars are nuclear fusion reactors. In their hot, dense cores, they fuse hydrogen atoms into helium, releasing immense amounts of energy. The energy released in the core, then slowly makes its way through the radiative…