3 Questions

OK, so maybe we’re not in the part of the country that witnessed a total solar eclipse earlier this week, but the sun isn’t the only star that deserves attention. T Coronae Borealis, often referred to as T CrB, is a nova that last erupted in 1946, and astronomers predict it will get all hot and bothered again between April and September of this year. While the star system is typically too dim to see with the naked eye, following the eruption it will appear with a brightness similar to that of the North Star for several days before it hides away again for roughly 80 years. We spoke with Santa Fe Children’s Museum STEM educator and NASA ambassador Asis Juan Carlos Gonzalez to learn more about our good friend T CrB’s long-awaited eruption, and why it matters. (Evan Chandler)

What causes an eruption like this to happen in the first place?

That happens when you have a binary star system. You generally have a dead star called a white dwarf—smaller stars that don’t go supernova. They kind of fall apart. The core gets hotter as it gets older and, after billions of years, the core gets so hot that its outer layers expand. At one point, it is so hot that those outer layers just kind of get ripped up into space because, as a star expands, the gravity can’t hold onto those outer layers as much as it can the center, so it just kind of falls apart. It’s almost like a snowball: If you crush it, it gets harder, heavier and technically increases its gravity. You can also stretch the snowball and it becomes fluffier. The gravity actually kind of lessens a little bit. So a red giant tends to be kind of loving, and so the gravity of the white dwarf can start pulling in material from that red giant around it. As it pulls material around it, once you get to about 10 million to 15 million degrees, you start fusion. But a white dwarf doesn’t have enough gravity to hold on to the energy generated by fusion, so it explodes.

Stars and space have fascinated humankind since the beginning of time. Why do you think that is?

If you think about it, they’re really weird. They’re just like these dots in the sky. And I’ve always wondered, ‘What would I be like thousands of years ago, or 100,000 years ago, if I was just sitting there looking at these dots? What would I think?’ I don’t know. They’re really mysterious, and then when you learn about them, how massive and how hot they get, it just seems like these impossible things in the sky that you can never touch because they’re just so far away. I do like stars. My primary interest is actually in planets. That’s what I studied—planetary science, but I love that stars are just these things that we can see react to the space around them in certain ways, and then they kind of have lives a little bit, even if they’re somewhat different lives than ours.

Why is it so important that we understand stars, the galaxy and the universe around us?

I just think it teaches you how special everything is. A lot of people get into conspiracy theories and stuff like that. If you don’t educate yourself, then everything is mundane, but if you learn about the stars and if you learn about the Earth…I think it makes everything less mundane to know, or even to know what we don’t know, actually; how special everything is around us—things that we take for granted. In a way, anything that happens in space is just something that you’ll never see again in your lifetime. Anything that happens in the sky is very unique, so that’s why they’re all important. Everything is just so massive that everything that happens in space is one opportune moment to see something that won’t happen again.