If you want to have some fun, fire up Twitter and search “what color is the sun.”

Because, yes, that is a thing on Elon Musk’s social media platform, and, turns out, most of us probably don’t know the actual color of the sun.

So, quick, before you read any further, go ahead and say what color you believe it is out loud.

Now, buckle up, because apparently NASA says our sun is really a “blue-green color.”

As is all things on social media, the discussion has a starting point. Turns out a user, Jacqui Deevoy, tweeted out a photo of the sun and wrote, “I’m just telling a person in their 20s that the sun used to be yellow when I was a child and he’s laughing. The last time he saw a yellow sun was on Teletubbies. Here’s the sun right now. White and a weird shape. How’s it looking where you are?”

It should be noted that her photo of the sun does appear to be a white light and is sort of a weird shape.

That tweet took off and has currently been viewed more than 6.1 million times. And the debate was off with most explaining why the sun was red or orange or yellow. But, according to The Washington Post, that is because our eyes can’t process the actual color of the sun.

“The sun would appear green if your eye could handle looking at it,” W. Dean Pesnell with NASA’s Solar Dynamics Observatory reportedly said. “Basically, when you look at the sun, it has enough of all the different colors in it and it’s so bright that everybody’s eyes are firing like crazy and saying, ‘It’s too bright for me to tell you want color it is.’ That’s why the sun looks white to us.”

So there is the not-so-obvious answer.

The sun is … blue-green.