10 Misconceptions About Space

People have a lot of weird misconceptions about space (thanks, Hollywood). Here are a few myths about the universe and their real explanations—and we hope you like NASA, because they're going to come up a lot.

1. The Sun is on fire.

Artist's rendering of the sun

When some people picture the Sun, they imagine something like a campfire or an object on fire. But the Sun is actually a ball of gas. It burns thanks to nuclear fusion, which happens in its core. Every second, 700 million tons of hydrogen gets converted into 695 million tons of helium. When this happens, energy is released as gamma rays, which get converted to light. So, the Sun emits light and heat, but it's not on fire, because there's no oxygen involved.

2. The Sun is the only star that has planets.

Jupiter and Mars in the solar system

Experts now believe that most of the stars in our Milky Way have planets surrounding them. Any planet that's found outside of our solar system is known as an exoplanet, and we can be pretty sure that they exist because they affect the way a star appears. One of the most common ways to detect exoplanets is to look for a decrease in light from certain stars at various times, which would indicate that a planet is passing in front of the star, affecting how the light appears to us.

3. Mercury is the closest planet to the Sun, so it's the hottest.

Colorized image of Venus's clouds
NASA/JPL // Public Domain

Distance from the Sun actually has little to do with the average temperature on a planet. Venus (the second planet from the Sun) is the hottest planet in the solar system, but that's because of its atmosphere, which contains mostly carbon dioxide and some nitrogen, making it very thick. Throughout the year the surface of Venus remains at a temperature of about 462°C. The surface of Mercury, on the other hand, has a lot of temperature variations. It can be as cold as -173°C at night, and during the day it might reach 427°C. Mercury has a very thin atmosphere, which is why there's so much variation in temperature.

4. People explode in space.

NASA astronaut performing a spacewalk
NASA/JSC // Public Domain

Space is a near-vacuum, which means that people can't survive out there for more than a few minutes—but exploding isn't a concern. A body exposed in space will expand and bloat, especially the air in the lungs and the water in body tissue, but human skin is actually tight enough to prevent exploding. A person exposed to space would eventually die when circulation stops, after dissolved gases in the blood form bubbles and block flow. Basically, it's like an extreme version of "the bends" that divers can get.

5. In the 1960s, NASA spent millions developing a pen that would write in space.

NASA astronaut writing with a space pen
NASA/JSC // Public Domain

This is a popular myth on the internet—and even in one episode of The West Wing. People tend to use this as a comparison between NASA and Soviet astronauts, who were smart enough to just bring pencils. But NASA used pencils as well, and they have the receipts to prove it. In 1965, NASA placed an order for 34 mechanical pencils from Houston's Tycam Engineering Manufacturing Incorporated. There was an independent company, the Fisher Pen Company, that developed a space pen for around $1 million. And later, both NASA and the Soviets started using Fisher's anti-gravity space pen (it was a great pen).

6. In space, you experience zero gravity.

NASA astronauts experiencing decreased gravity
NASA/JSC // Public Domain">NASA/JSC // Public Domain

Gravity is considered the most important force in the universe, and it doesn't just go away when we leave Earth. Gravity is necessary for everything from the Moon's ability to orbit the Earth to the Sun staying put in the Milky Way. What astronauts actually experience in space is what NASA calls micro-gravity. It has nothing to do with the actual strength of gravity, which is only very slightly less on the International Space Station. It's because astronauts are constantly falling, so they seem weightless.

7. Black holes are like vacuums.

As we learn more and more about black holes, experts are more likely to compare them to Venus flytraps than vacuums. Black holes don't suck up everything nearby; instead, they sit pretty dormant, then if a star approaches it and gets too close, the black hole becomes active. And still, only some of the objects nearby get ripped apart by the black hole.

8. The Moon orbits Earth once a day.

Earth's moon
NASA/JPL/USGS // Public Domain

It takes about 27.3 days for the Moon to orbit Earth. This is known as a sidereal month. It's worth noting that the Moon's orbit isn't considered regular—it has variations, and there are upwards of five different months that astronomers recognize.

9. There's a dark side of the Moon.

Earth's Moon from the International Space Station
NASA/JSC // Public Domain

As the Moon is orbiting Earth, it's also rotating on its axis, so we're always seeing the same side of the Moon. But the opposite side isn't dark: it gets the same amount of sunlight as the other side.

10. A light-year measures time.

It actually measures distance. NASA defines a light-year as "the total distance that a beam of light, moving in a straight line, travels in one year." Light travels at around 300,000 kilometers per second, so a light-year is around 10 trillion (10,000,000,000,000) kilometers.

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This story was republished in 2019.

This Cool T-Shirt Shows Every Object Brought on the Apollo 11 Mission

Fringe Focus
Fringe Focus

NASA launched the Apollo 11 mission on July 16, 1969, ending the space race and beginning a new era of international space exploration. Just in time for the mission's 50th anniversary this year, Fringe Focus is selling a t-shirt that displays every item the Apollo 11 astronauts brought with them to the Moon.

The design, by artist Rob Loukotka, features some of the iconic objects from the mission, such as a space suit and helmet, as well as the cargo that never made it to primetime. Detailed illustrations of freeze-dried meals, toiletries, and maintenance kits are included on the shirt. The artist looked at 200 objects and chose to represent some similar items with one drawing, ending up with 69 pictures in total.

The unisex shirt is made from lightweight cotton, and comes in seven sizes ranging from small to 4XL. It's available in black heather or heather midnight navy for $29.

If you really like the design, the artwork is available in other forms. The same illustration has also been made into poster with captions indicating which pictures represent multiple items of a similar nature.

The International Space Station Will Start Accepting Visitors … For $58 Million


If you've ever wanted to visit the International Space Station, your chance is coming soon—assuming you have a few million set aside. Recently, NASA announced that this orbiting outpost will be open to private citizens starting in 2020.

However, it won't be cheap. According to The Denver Post, each trip could last up to 30 days, and NASA estimates the cost of a round trip at $58 million, as well as an additional $35,000 charge per night. And, it's not just for kicks—you need to have a mission of your own. The space agency is allowing companies that want to conduct commercial or marketing work to send employees to the ISS as long as they meet one of the three requirements:

  • require the unique microgravity environment to enable manufacturing, production, or development of a commercial application;
  • have a connection to NASA's mission; or
  • support the development of a sustainable low-Earth orbit economy

The space station had a visitor back in 2001—Californian businessman Dennis Titobecame history's first space tourist when he spent a week aboard the ISS with two Russian cosmonauts who took him out there on a Russian spacecraft—but this would be a first for NASA. The agency was opposed to training and flying with Tito back in 2001; at the time, NASA administrator Daniel Goldin said, "Space is dangerous. It's not a joyride. Space is not about egos."

Now, NASA is ready to open the shuttle doors to private citizens. In addition to U.S. citizens, those from other countries are eligible to travel as long as they fly on a U.S.-operated rocket. These lucky private astronauts will have to go through the same medical checks, physical training, and certification procedures as crew members before traveling—a process that could take up to two years.

Along with this exciting news, NASA has bigger plans in mind. They are considering the possibility of a private sector company eventually taking control of the station and paying for its expensive upkeep. NASA has yet to announce when this transition would take place, but said in a statement that the "ultimate goal in low-Earth orbit is to partner with industry to achieve a strong ecosystem in which NASA is one of many customers purchasing services and capabilities at lower cost."

In addition, they hope that the revenue will assist in the operational costs for NASA's Artemis program, which is focused on sending astronauts—including the first woman—to the Moon by 2024.

[h/t The Denver Post]