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.

8 Facts About David Bowie's 'Space Oddity'

Express/Express/Getty Images
Express/Express/Getty Images

Fifty years ago, on July 24, 1969, astronauts walked on the Moon for the first time. Just a few weeks earlier, another space-age event had rocked the world: David Bowie’s single “Space Oddity” hit airwaves. The song, whose lyrics tell the story of an astronaut’s doomed journey into space, helped propel the artist to icon status, and five decades later, it’s still one of his most popular works. In honor of its 50th anniversary, here are some facts about the stellar track.

1. "Space Oddity" was inspired by 2001: A Space Odyssey.

Many listeners assumed that "Space Oddity" was riffing on the Apollo 11 Moon landing of 1969, but it was actually inspired by a Stanley Kubrick film released a year earlier. Bowie watched 2001: A Space Odyssey multiple times when it premiered in theaters in 1968. “It was the sense of isolation I related to,” Bowie told Classic Rock in 2012. “I found the whole thing amazing. I was out of my gourd, very stoned when I went to see it—several times—and it was really a revelation to me. It got the song flowing.”

2. "Space Oddity" was also inspired by heartbreak.

The track was also partly inspired by the more universal experience of heartbreak. Bowie wrote the song after ending his relationship with actress Hermione Farthingale. The break inspired several songs, including “Letter to Hermione” and “Life on Mars,” and in “Space Oddity,” Bowie’s post-breakup loneliness and melancholy is especially apparent.

3. "Space Oddity" helped him sign a record deal.

In 1969, a few years into David Bowie’s career, the musician recorded a demo tape with plans to use it to land a deal with Mercury Records. That tape featured an early iteration of “Space Oddity,” and based on the demo, Mercury signed him for a one-album deal. But the song failed to win over one producer. Tony Visconti, who produced Bowie’s self-titled 1969 album, thought the song was a cheap attempt to cash in on the Apollo 11 mission, and he tapped someone else to produce that particular single.

4. The BBC played "Space Oddity" during the Moon landing.

"Space Oddity" was released on July 11, 1969—just five days before NASA launched Apollo 11. The song doesn’t exactly sound like promotional material for the mission. It ends on a somber note, with Major Tom "floating in a tin can" through space. But the timing and general subject matter were too perfect for the BBC to resist. The network played the track over footage of the Moon landing. Bowie later remarked upon the situation, saying, "Obviously, some BBC official said, 'Oh, right then, that space song, Major Tom, blah blah blah, that’ll be great. 'Um, but he gets stranded in space, sir.' Nobody had the heart to tell the producer that."

5. David Bowie recorded an Italian version of "Space Oddity."

The same year "Space Oddity" was released, a different version David Bowie recorded with Italian lyrics was played by radio stations in Italy. Instead of directly translating the English words, the Italian songwriter Mogul was hired to write new lyrics practically from scratch. "Ragazzo Solo, Ragazza Sola" ("Lonely Boy, Lonely Girl") is a straightforward love song, and Major Tom is never mentioned.

6. Major Tom appeared in future songs.

Major Tom, the fictional astronaut at the center of "Space Oddity," is one of the most iconic characters invented for a pop song. It took a decade for him to resurface in David Bowie’s discography. In his 1980 single "Ashes to Ashes," the artists presents a different version of the character, singing: "We know Major Tom's a junkie/Strung out in heaven's high/Hitting an all-time low." Bowie also references Major Tom in "Hallo Spaceboy" from the 1995 album Outside.

7. "Space Oddity" is featured in Chris Hadfield's ISS music video.

When choosing a song for the first music filmed in space, Canadian astronaut Chris Hadfield naturally went with David Bowie’s out-of-this-world anthem. The video above was recorded on the International Space Station in 2013, with Hadfield playing guitar and singing from space and other performers providing musical accompaniment from Earth. Some lyrics were tweaked for the cover. Hadfield mentions the "Soyuz hatch" of the capsule that would eventually shuttle him to Earth.

8. "Space Oddity" played on the Tesla that Elon Musk sent to space.

Dummy in Tesla roadster in space with Earth in background.
SpaceX via Getty Images

In 2018, Elon Musk used SpaceX's Falcon Heavy rocket to launch his Tesla Roadster into space. The car was decked out with pop culture Easter eggs—according to Musk, "Space Oddity" was playing over the car’s radio system during the historic journey. The dummy’s name, Starman, is the name of another space-themed song on Bowie's 1972 masterpiece The Rise and Fall of Ziggy Stardust and the Spiders from Mars.

The Washington Monument Is Transforming Into a Full-Scale Saturn V Rocket for the 50th Anniversary of the Apollo 11 Moon Landing

The Saturn V rocket takes off on July 16, 1969.
The Saturn V rocket takes off on July 16, 1969.

Where better to celebrate the 50th anniversary of the first Moon landing than in front of a revered national monument that also happens to resemble a giant rocket?

Next week, DCist reports, the Smithsonian National Air and Space Museum will project an image of the 363-foot-tall Saturn V rocket that launched Buzz Aldrin, Neil Armstrong, and Michael Collins into space on July 16, 1969, onto the 555-foot-tall Washington Monument. Underneath the monument, flanked by screens playing a 17-minute program about the Moon landing, will be a 40-foot-wide replica of the iconic Kennedy Space Center countdown clock that NASA has called “one of the most-watched timepieces in the world.”

Illustration of the Saturn V rocket projected onto the Washington Monument
An illustration of what the Saturn V projection will look like on the Washington Monument.
Smithsonian National Air and Space Museum

Projecting an image onto an irregular object is a little more complicated than doing so on a run-of-the-mill, rectangular movie screen. The process is called projection mapping, which uses augmented reality to conform the projection to the object, making it seem like the projection is actually just part of the object. 59 Productions, the company behind this program, also created the video design for London’s 2012 Olympic Games opening ceremony and won a 2015 Tony Award for the video design of Christopher Wheeldon’s stage revival of An American in Paris.

So who exactly has to approve transforming one of our nation’s most famous monuments into a really tall, skinny optical illusion? In this case, the House of Representatives, the Senate, the secretary of the interior, and the president himself. Both houses of Congress unanimously passed the bipartisan resolution, H.J. Res. 60 [PDF], in mid-June, and the president signed it on July 5.

According to Ellen Stofan, director of the Smithsonian National Air and Space Museum, the larger-than-life nature of the setting befits the occasion. “The Washington Monument is a symbol of our collective national achievements and what we can and will achieve in the future,” she told DCist. “It took 400,000 people from across the 50 states to make Apollo a reality. This program celebrates them, and we hope it inspires generations too young to have experienced Apollo firsthand to define their own moonshot.”

You can see the Saturn V projection from 9:30 p.m. to 11:30 p.m. on July 16, 17, and 18. The best view is on the National Mall in front of the Smithsonian Institution Building (also known as the “Castle”) between 9th and 12th streets. The entire program, titled “Apollo 50: Go for the Moon,” will run at 9:30 p.m., 10:30 p.m., and 11:30 p.m. on Friday, July 19, and Saturday, July 20.

[h/t DCist]