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The Sun's pretty great. It gives us light and warmth to enjoy, sunsets to paint... and makes life on Earth possible. So you might be tempted to head out and explore that thing -- which we did, in an imaginary, indestructible spaceship. But if we hadn't used that invincible ship, all that heat and radiation would have gotten super deadly, super fast. In a regular NASA EVA spacesuit, for example - the kind that you would use for spacewalks -- you'd probably die somewhere before you got halfway to the Sun. But it wouldn't be from the heat. It would be from the other kinds of radiation that are constantly streaming out of the Sun in different forms. Some of that radiation comes from high-energy protons, electrons, and alpha particles, which are basically helium atoms without the electrons. The spacesuit would help with that a little, because its thick fabric would block many of those particles and most UV radiation. But the Sun also emits more dangerous kinds of light, like X-rays and gamma rays. Blocking a good amount of gamma and X-rays would mean you'd have to line the spacesuit with a layer of lead. Astronaut suits don't normally have that, because lead would make them a lot heavier and much more difficult to bring up into space in the first place, and also, I imagine, harder to move around. Since astronauts working on the International Space Station aren't usually out for too long, they're pretty safe without it. Floating toward the Sun means a lot of radiation exposure, though - radiation that would probably end up killing you sometime before you reached the halfway point by basically destroying too many cells to keep your body going. Halfway to the sun is still pretty far, though. 

The ship we used for the Apollo 10 mission to the moon was the fastest manned vehicle in human history, moving more than eleven kilometers every seconds on its way back from the Moon in 1969. If you were going as fast as Apollo 10 at its fastest, it would still take two and a half months to travel half of the 150 million kilometers between Earth and the Sun. You could get a lot closer if you invented -- and wore -- a spacesuit that blocked out all kinds of radiation except for infrared light, which is what we feel as heat. Most spacesuits are designed to withstand temperatures up to about 400 Kelvin, and you'd probably be fine until you got around 95% of the way to the Sun. That's when the suit would go from being a life-sustaining pocket of the universe just for you...to a kind of personal pressure cooker. That's just 6.8 million kilometers away from the solar surface, which is pretty close! Especially considering that the Sun's surface is almost 6,000 Kelvin. You could only get that close because there's nothing in space to conduct or hold onto the heat except for your body, meaning that the only thing heating you up would be the infrared radiation hitting you directly. The farther you are from the Sun, the less of its light hits you. So you'd have to get pretty close before you'd start to feel the burn.

But you wouldn't necessarily need to invent a whole new spacesuit to get that close; an ordinary spaceship would do. It would be able to withstand higher temperatures, sure, but it would also be better at absorbing heat than you are, and those two factors would pretty much cancel each other out. So you would still only get about 95% of the way to the Sun before the ship started melting - a five month trip if you were going as fast as Apollo 10. So I hope you are planning on bringing a good book or two on your way to your fiery demise. 

Thanks for watching this episode of SciShow Space, and thank you especially to all of our patrons on Patreon, who make this show possible, allow us to keep doing it, and paying all of the people. Valerie and Lou...who are there, I promise! It's not just me doing this. We work hard and I hope you like it. If you want to learn more, you can go to youtube.com/scishowspace and subscribe. 

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