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. 

8 Great Gifts for People Who Work From Home

World Market/Amazon
World Market/Amazon

A growing share of Americans work from home, and while that might seem blissful to some, it's not always easy to live, eat, and work in the same space. So, if you have co-workers and friends who are living the WFH lifestyle, here are some products that will make their life away from their cubicle a little easier.

1. Folding Book Stand; $7

Hatisan / Amazon

Useful for anyone who works with books or documents, this thick wire frame is strong enough for heavier textbooks or tablets. Best of all, it folds down flat, so they can slip it into their backpack or laptop case and take it out at the library or wherever they need it. The stand does double-duty in the kitchen as a cookbook holder, too.

Buy It: Amazon

2. Duraflame Electric Fireplace; $179

Duraflame / Amazon

Nothing says cozy like a fireplace, but not everyone is so blessed—or has the energy to keep a fire going during the work day. This Duraflame electric fireplace can help keep a workspace warm by providing up to 1000 square feet of comfortable heat, and has adjustable brightness and speed settings. They can even operate it without heat if they just crave the ambiance of an old-school gentleman's study (leather-top desk and shelves full of arcane books cost extra).

Buy It: Amazon

3. World Explorer Coffee Sampler; $32

UncommonGoods

Making sure they've got enough coffee to match their workload is a must, and if they're willing to experiment with their java a bit, the World Explorer’s Coffee Sampler allows them to make up to 32 cups using beans from all over the world. Inside the box are four bags with four different flavor profiles, like balanced, a light-medium roast with fruity notes; bold, a medium-dark roast with notes of cocoa; classic, which has notes of nuts; and fruity, coming in with notes of floral.

Buy it: UncommonGoods

4. Lavender and Lemon Beeswax Candle; $20

Amazon

People who work at home all day, especially in a smaller space, often struggle to "turn off" at the end of the day. One way to unwind and signal that work is done is to light a candle. Burning beeswax candles helps clean the air, and essential oils are a better health bet than artificial fragrances. Lavender is especially relaxing. (Just use caution around essential-oil-scented products and pets.)

Buy It: Amazon

5. HÄNS Swipe-Clean; $15

HÄNS / Amazon

If they're carting their laptop and phone from the coffee shop to meetings to the co-working space, the gadgets are going to get gross—fast. HÄNS Swipe is a dual-sided device that cleans on one side and polishes on the other, and it's a great solution for keeping germs at bay. It's also nicely portable, since there's nothing to spill. Plus, it's refillable, and the polishing cloth is washable and re-wrappable, making it a much more sustainable solution than individually wrapped wipes.

Buy It: Amazon

6. Laptop Side Table; $100

World Market

Sometimes they don't want to be stuck at a desk all day long. This industrial-chic side table can act as a laptop table, too, with room for a computer, coffee, notes, and more. It also works as a TV table—not that they would ever watch TV during work hours.

Buy It: World Market

7. Moleskine Classic Notebook; $17

Moleskin / Amazon

Plenty of people who work from home (well, plenty of people in general) find paper journals and planners essential, whether they're used for bullet journaling, time-blocking, or just writing good old-fashioned to-do lists. However they organize their lives, there's a journal out there that's perfect, but for starters it's hard to top a good Moleskin. These are available dotted (the bullet journal fave), plain, ruled, or squared, and in a variety of colors. (They can find other supply ideas for bullet journaling here.)

Buy It: Amazon

8. Nexstand Laptop Stand; $39

Nexstand / Amazon

For the person who works from home and is on the taller side, this portable laptop stand is a back-saver. It folds down flat so it can be tossed into the bag and taken to the coffee shop or co-working spot, where it often generates an admiring comment or three. It works best alongside a portable external keyboard and mouse.

Buy It: Amazon

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Uranus Reaches Opposition on Halloween in 2020

Christine Schmitt, Flickr // CC BY-NC-ND 2.0
Christine Schmitt, Flickr // CC BY-NC-ND 2.0

Uranus is roughly 1.75 billion miles away from Earth, which makes it difficult to spot without a telescope most nights. But on Saturday, October 31, the seventh planet from the sun will be worth looking for. Uranus reaches opposition that night, making it appear extra bright in the night sky.

What Is Uranus at Opposition?

An opposition occurs when the Earth falls perfectly between another planet and the sun. When this happens, the sun's light appears to fully illuminate the planet's surface, boosting its brightness level to the maximum.

Uranus reaches opposition on October 31 in 2020. During this event, Uranus will hit a limiting magnitude of 5.86, which is about the minimum brightness for what's visible with the naked eye.

How to Look for Uranus at Opposition

Spotting Uranus at opposition will be slightly more difficult in 2020 than in years past. The phenomenon coincides with a full moon that will make dimmer stars and planets—including Uranus—harder to see in the night sky. The planet sits in the constellation Aries, which regrettably appears close to the moon for most of the night.

Uranus should appear as a small, blue-green disc when using a telescope. Even if you have trouble spotting the seventh planet, it will still be worth checking out the night sky on October 31: Halloween this year coincides with a rare blue moon.