7 Shining Facts About the Sun

NASA
NASA

Isaac Asimov described the solar system as the Sun, Jupiter, and debris. He wasn't wrong—the Sun is 99.8 percent of the mass of the solar system. But what is the giant ball of fire in the sky? How does it behave and what mysteries remain? Mental Floss spoke to Angelos Vourlidas, an astrophysicist and the supervisor of the Solar Section at Johns Hopkins University Applied Physics Laboratory, to learn what scientists know about the Sun—and a few things they don't.

1. IT'S A GIANT NUCLEAR FUSION REACTOR.

The Sun is so incomprehensibly big that it's almost pointless to bother trying to imagine its size. Our star is about 860,000 miles across. It is so big that 1.3 million Earths could fit inside of it. The Sun is 4.5 billion years old, and should last for another 6.5 billion years. When it faces the final curtain, it will not go supernova, however, as lacks the mass for such an end. Rather, the Sun will grow to a red giant—destroying the Earth in the process, if we last that long, which we won't—and then contract down to become a white dwarf.

The Sun is 74 percent hydrogen and 25 percent helium, with a few other elements thrown in for flavor, and every second, nuclear reactions at its core fuse hundreds of millions of tons of hydrogen into hundreds of millions of tons of helium, releasing the heat and light that we love so very much.

2. IT HAS A GALACTIC-SCALE ORBIT.

The Sun rotates, though not quite the same way as a terrestrial planet like the Earth. Like the gas and ice giants, the Sun's equator and poles complete their rotations at different times. It takes the Sun's equator 24 days to complete a rotation. Its poles poke along and rotate every 35 days. Meanwhile, the Sun actually has its own orbit. Moving at 450,000 miles per hour, the Sun is in orbit around the center of the Milky Way galaxy, making a full loop every 230 million years.

3. IT'S HOT IN ODD WAYS.


The solar corona as captured every two hours for four days. Red is cool (~80,000°F), while yellow is hot (~2,800,000°F).
Angelos Vourlidas, JHU/APL

The Sun's temperatures leave astrophysicists puzzled. At its core, it reaches a staggering 27,000,000°F. Its surface is a frosty 10,000°F, which, as NASA notes, is still hot enough to make diamonds boil. Here's the weird part, though. Once you get into the higher parts of the Sun's corona, temperatures again rise to 3,500,000°F. Why? Nobody knows!

4. THE SUN HAS AN ATMOSPHERE—AND THE EARTH IS INSIDE IT.

If you saw the total solar eclipse earlier this year, you saw the Sun turn black, ringed by a shimmering white corona. That halo was part of the Sun's atmosphere. And it's a lot bigger than that. In fact, the Earth is inside of the Sun's atmosphere. "It basically goes as far away as Jupiter," Vourlidas tells Mental Floss. The Sun is a semi-chaotic system. Every 100 years or so, the Sun seems to go into a small "sleep," and for two or three decades, its activity is reduced. When it wakes, it becomes much more active and violent. Scientists are not sure why that is. Presently we are in one of those solar lulls.

5. THE IRON IN YOUR BLOOD COMES FROM THE SUN'S SIBLINGS.

The Sun lacks a solid core. At 27,000,000°F, it's all plasma down there. "That's where most of the heavy elements like iron and uranium are created—at the cores of stars," Vourlidas says. "When the stars explode, they are released into space. Planets form out of that debris, and that's where we get the same iron in our blood and the carbon in our cells. They were made in some star." Not ours, obviously, but a star that exploded in our neighborhood before our Sun was born. Other elements created from the cores of stars include gold, silver, and plutonium. That is what Carl Sagan meant when he said that we are children of the stars.

6. THE HOLY GRAIL OF SUN SCIENCE IS UNDERSTANDING ERUPTIONS.

The ability to predict solar storms is the holy grail for astrophysicists who study the Sun. During a coronal mass ejection, a billion tons of plasma material can be blown from the Sun at millions of miles per hour. The eruptions carry around 300 petawatts of energy—that's 50,000 times the amount of energy that humans use in a single year. As the structures travel from the Sun, they expand, and when they hit the Earth, a percentage of their energy is imparted. Those impacts can create havoc. Spacecraft are affected, airliners receive surges of x-rays, and the energy grid can be disrupted—one day perhaps catastrophically so. "Our models say it can happen every 200 years," says Vourlidas, "but the Sun doesn't know about our models."

The last such strike on the Earth is believed to have occurred in 1859. The telegraph system collapsed, but the effect on society was minimal overall. (The widespread use of electric lighting and the first power grids were still decades away.) If the Earth were to sustain a similar such destructive event today, the effects might be devastating. "It is the most violent phenomenon in our solar system," Vourlidas explains. "We need to know when such an amount of plasma has left the Sun, whether it will hit the Earth, and how hard it is going to slap us." Such foresight would allow spacecraft to power down sensitive instruments and power grids to switch off where necessary, among other things.

7. NASA'S NEXT STOP: THE SUN.


Wind moving off of the Sun in visible light. If you were in a spaceship and didn't melt, that's what you would see. The zooming effect simulates what an imager on the Parker Solar Probe will see.
Angelos Vourlidas, JHU/APL

Next year, NASA will launch the Applied Physics Laboratory's Parker Solar Probe to "kiss" the Sun. It will travel to within 4 million miles of our star—the closest we've ever come—and will study the corona and the solar wind. "At the moment, the only way we understand that system is by seeing what the properties of the wind are at Earth, and then trying to extrapolate back toward the Sun," says Vourlidas. "It's an indirect exercise. But the probe will measure the wind—how fast it is, how dense, what is the magnetic field—across multiple locations as it orbits the Sun." Once scientists get those measurements, theorists will attempt to devise new models of the solar wind, and ultimately help better predict solar storms and space weather events.

Editor's Note: This post has been updated. 

This $49 Video Game Design Course Will Teach You Everything From Coding to Digital Art Skills

EvgeniyShkolenko/iStock via Getty Images
EvgeniyShkolenko/iStock via Getty Images

If you spend the bulk of your free time playing video games and want to elevate your hobby into a career, you can take advantage of the School of Game Design’s lifetime membership, which is currently on sale for just $49. You can jump into your education as a beginner, or at any other skill level, to learn what you need to know about game development, design, coding, and artistry skills.

Gaming is a competitive industry, and understanding just programming or just artistry isn’t enough to land a job. The School of Game Design’s lifetime membership is set up to educate you in both fields so your resume and work can stand out.

The lifetime membership that’s currently discounted is intended to allow you to learn at your own pace so you don’t burn out, which would be pretty difficult to do because the lessons have you building advanced games in just your first few hours of learning. The remote classes will train you with step-by-step, hands-on projects that more than 50,000 other students around the world can vouch for.

Once you’ve nailed the basics, the lifetime membership provides unlimited access to thousands of dollars' worth of royalty-free game art and textures to use in your 2D or 3D designs. Support from instructors and professionals with over 16 years of game industry experience will guide you from start to finish, where you’ll be equipped to land a job doing something you truly love.

Earn money doing what you love with an education from the School of Game Design’s lifetime membership, currently discounted at $49.

 

School of Game Design: Lifetime Membership - $49

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Where to Watch SpaceX’s Historic Astronaut Launch Live

Joe Raedle/Getty Images
Joe Raedle/Getty Images

SpaceX will make history today when it launches its first crewed spacecraft from Cape Canaveral, Florida, at 4:33 p.m. EDT. Powered by a Falcon 9 rocket, the Crew Dragon spacecraft will transport NASA astronauts Doug Hurley and Bob Behnken to the International Space Station, marking the company's first-ever crewed mission and the first crewed launch from the U.S. since 2011. If you want to watch the momentous event from home, there are plenty of ways to stream it live online.

Both SpaceX and NASA will be hosting livestreams of the May 27 launch. NASA's webcast kicks off at 12:15 p.m. EDT today with live looks at the Crew Dragon and Falcon 9 rocket at the Kennedy Space Center. The feed will continue streaming until late in the morning of Thursday, May 28, when the spacecraft is set to dock at the International Space Station. You can catch the coverage on NASA's website, its social media channels, or on the NASA TV channel through cable or satellite. SpaceX's stream also starts at 12:15 p.m. EDT, and it will be broadcast on the company's YouTube channel. (You can watch the video below).

Several television networks will be covering the event, with ABC and National Geographic airing "Launch America: Mission to Space Live" at 3 p.m., and Discovery and the Science Channel showing "Space Launch Live: America Returns to Space" at 2 p.m. If you're looking for more online streaming options, the American Museum of Natural History and Intrepid Museum in New York City will be hosting live events to celebrate the launch this afternoon on YouTube.

The launch has been scheduled down to the minute, but SpaceX still has time to change that depending on the weather. If today's launch doesn't happen according to plan, there are windows on May 30 and May 31 set aside for second attempts.

[h/t TechCrunch]