Before We Leave the Ground
The planet Neptune was found with math before anyone pointed a telescope at it. Urbain Le Verrier calculated where it had to be based on perturbations in Uranus’s orbit, sent a letter to an observatory in Berlin, and they found it the same night within one degree of his prediction. That was 1846. I’ve opened trivia nights with that story and watched a room of people who thought space was all about memorizing planet names suddenly realize they were in deeper water than expected.
Here’s who I wrote this for: you’ve watched a few documentaries. You probably know what a light-year measures. You’ve got opinions about Pluto. You think you can name the Apollo 11 crew. And on about a third of these questions, that confidence is going to betray you in the most satisfying way possible. These are 100 space trivia questions I’ve tested on real people in real rooms, and I know exactly where they land. Some will feel like a gift. Some will start arguments. A few will sit with you for days.
The Ones That Feel Easy Until They Don’t
1. How many planets in our solar system have rings?
I love opening with this because every table immediately shouts “one” or “two.” The look on people’s faces when they hear the answer is worth the whole night.
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Four. Jupiter, Saturn, Uranus, and Neptune all have ring systems. Saturn’s are just the showiest. Most people say one or two, because Saturn’s rings dominate every image they’ve ever seen and Uranus gets mentioned occasionally. Jupiter and Neptune’s rings are faint and dark, discovered relatively recently, and they never show up in the mental picture people carry of those planets.
2. What is the closest star to Earth?
This is a trick question hiding in plain sight. About half the room gets it immediately and the other half overthinks it into oblivion.
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The Sun. The most common wrong answer is Proxima Centauri, which is the closest star other than the Sun. People hear “star” and their brain skips right past the one keeping them alive.
3. What color is a sunset on Mars?
This one splits rooms right down the middle. People who’ve seen the photos know. Everyone else guesses based on what they think a red planet should do to light.
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Blue. Mars’s thin atmosphere scatters light differently than Earth’s. The fine dust particles scatter red light forward and blue light stays near the Sun. It’s the opposite of what most people expect, and the photos from the Curiosity rover are genuinely haunting.
4. Which planet in our solar system has the most moons?
This answer has actually changed in recent years, which makes it a fun one to watch people argue about. Someone always says Jupiter with absolute certainty.
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Saturn, with over 140 confirmed moons as of recent surveys. Jupiter held the record for a long time and still has over 90, but new discoveries in the 2020s pushed Saturn well ahead. The common wrong answer is Jupiter, and it was correct until fairly recently.
5. What does the “SS” in ISS stand for?
Dead simple, but I’ve watched confident people freeze on this one because they suddenly aren’t sure if the first S is “Space” or “Station.”
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Space Station. International Space Station. The hesitation usually comes from people second-guessing whether it’s “Space Station” or “Space Shuttle” or some other combination.
6. How long does it take sunlight to reach Earth?
People who know this feel great about themselves. People who don’t tend to guess wildly in both directions.
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About 8 minutes and 20 seconds. I’ve heard guesses from “instantly” to “several hours.” The light you’re seeing right now left the Sun before you started reading this article.
7. What was the first animal sent into orbit around Earth?
Everyone wants to say a monkey. The story behind this one is sadder than most people expect.
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Laika, a dog, aboard the Soviet spacecraft Sputnik 2 in 1957. She was a stray from the streets of Moscow. The mission was always one-way. Fruit flies were launched earlier on suborbital flights, but Laika was the first animal to orbit. The common wrong answer is Ham the chimpanzee, who came later and actually survived.
8. Which planet rotates on its side, with an axial tilt of about 98 degrees?
There’s usually one person at every table who knows this instantly and can’t believe nobody else does.
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Uranus. Something massive likely collided with it early in the solar system’s history, knocking it onto its side. This means its poles take turns pointing almost directly at the Sun.
9. What is the Great Red Spot?
A warm-up, sure. But I include it because the scale of the answer always resets the room.
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A massive storm on Jupiter, an anticyclonic storm that has been raging for at least 350 years. It’s large enough to fit Earth inside it. At various points in history, it could have fit two or three Earths, though it has been shrinking.
10. In what year did humans first walk on the Moon?
If you get this wrong, that’s fine, but your teammates won’t let you forget it.
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1969. Apollo 11, July 20th. Neil Armstrong and Buzz Aldrin walked; Michael Collins orbited above.
Where Confidence Goes to Die
11. How many people have walked on the Moon?
This is where the overconfident start sweating. Everyone knows Armstrong. Most know Aldrin. After that, the names get foggy fast.
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Twelve. Across six Apollo missions (11, 12, 14, 15, 16, and 17). The most common wrong answers are two and six. People forget there were five more landing missions after Apollo 11.
12. What is the hottest planet in our solar system?
Logic says Mercury. Logic is wrong.
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Venus. Despite being farther from the Sun than Mercury, Venus’s thick carbon dioxide atmosphere creates a runaway greenhouse effect, pushing surface temperatures to about 475°C (900°F). Mercury has no atmosphere to trap heat. This is the single most common wrong answer in all of space trivia, and I have never once run a night where someone didn’t argue about it.
13. What is the largest volcano in the solar system?
If you know your Mars geography, this is free points. If you don’t, you’re about to learn something that’ll change how you think about that planet.
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Olympus Mons on Mars. It’s about 13.6 miles (22 km) high and roughly the size of the state of Arizona at its base. It’s so wide that if you stood on its edge, the curvature of Mars would hide the summit from view.
14. What year was Pluto reclassified as a dwarf planet?
People always think this happened more recently than it did. The emotional wound is still fresh, so they compress the timeline.
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2006, by the International Astronomical Union. The common wrong guess is somewhere around 2012-2015. It’s been almost two decades and people still haven’t forgiven the IAU.
15. What is the name of the boundary where the Sun’s solar wind is stopped by the interstellar medium?
This one separates the casual fans from the people who actually read about Voyager.
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The heliopause. Voyager 1 crossed it in 2012, becoming the first human-made object to enter interstellar space. People often confuse this with the heliosphere (the bubble itself) or the Oort Cloud (which is much farther out).
16. Which Apollo mission suffered an oxygen tank explosion and had to abort its lunar landing?
Tom Hanks has done a lot for space trivia participation rates.
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Apollo 13, in April 1970. “Houston, we’ve had a problem” is the actual quote, though the movie changed it to present tense. The crew used the lunar module as a lifeboat and made it home alive.
17. What element makes up most of the Sun’s mass?
Straightforward, but a surprising number of people say helium. Which is ironic, given helium’s name.
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Hydrogen, making up about 73% of the Sun’s mass. Helium accounts for about 25%. The word “helium” literally comes from “helios,” the Greek word for sun, because it was detected in the Sun’s spectrum before it was found on Earth.
18. What was the first space station?
Almost everyone says Mir. The actual answer predates it by two decades.
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Salyut 1, launched by the Soviet Union in 1971. Mir didn’t launch until 1986. Skylab, the American station, launched in 1973. The Soviets were first by a comfortable margin on this one.
19. What is the farthest human-made object from Earth?
Most people know this one, but they don’t always know just how far “far” means.
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Voyager 1, launched in 1977. As of the mid-2020s, it’s over 15 billion miles from Earth. A signal from Voyager 1 takes more than 22 hours to reach us, traveling at the speed of light. It’s still sending data back, though its power is fading.
20. How many Space Shuttles were built for spaceflight?
People always forget one. Or add one. The number is oddly hard to pin down from memory.
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Five: Columbia, Challenger, Discovery, Atlantis, and Endeavour. Enterprise was built for atmospheric test flights only and never went to space. The common wrong answer is six, from people who count Enterprise.
The Solar System Is Weirder Than You Think
21. Which moon in our solar system has a thicker atmosphere than Earth?
A moon with weather. A moon with lakes. This one always gets a reaction.
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Titan, Saturn’s largest moon. Its atmosphere is about 1.5 times denser than Earth’s, composed primarily of nitrogen with traces of methane. It has liquid methane lakes, rain, and weather patterns.
22. What is the smallest planet in our solar system?
Before 2006, this had a different answer. Now it’s a question about whether you’ve updated your mental model.
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Mercury. Before Pluto’s reclassification, Pluto held this title. People who grew up before 2006 sometimes still say Pluto out of reflex, even when they know better.
23. On which planet does it rain diamonds?
I’ve seen people laugh out loud when they hear this question, convinced it’s a joke. It’s not.
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Both Neptune and Uranus are believed to have diamond rain. Extreme pressure and temperature deep in their atmospheres compress carbon into diamond crystals that fall like hailstones. Lab experiments have confirmed this is physically possible under those conditions.
24. What is the tallest mountain in the solar system, measured from base to peak?
If you said Olympus Mons three questions ago, you might think this is the same answer. It depends on how you measure.
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Olympus Mons on Mars, at about 13.6 miles (22 km) from base to summit. However, if measured from the center of the body, the peak of Rheasilvia on the asteroid Vesta actually extends higher relative to its surroundings. But base-to-peak, Olympus Mons wins.
25. Which planet has the shortest day?
Size matters here, but not the way most people think.
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Jupiter, which completes a rotation in just under 10 hours. Despite being the largest planet, it spins the fastest. Saturn is close behind at about 10.7 hours. People often guess Mercury, confusing slow orbital period with slow rotation.
26. What is the Roche limit?
This is a pub trivia question that sounds like a final exam question. But once you explain it, everyone gets it.
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The distance within which a celestial body, held together only by its own gravity, will be torn apart by tidal forces from a larger body. It’s why Saturn’s rings exist where they do. Any moon that wanders inside the Roche limit gets shredded.
27. Which planet spins backward compared to most other planets in the solar system?
There are technically two correct answers here, but one is the one everyone’s looking for.
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Venus. It rotates clockwise (retrograde rotation) when viewed from above its north pole, opposite to most planets. Uranus also technically qualifies due to its extreme axial tilt, but Venus is the classic answer. On Venus, the Sun rises in the west.
28. What is the largest known structure in the observable universe?
Scale questions are my favorite because nobody’s intuition works at these distances.
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The Hercules-Corona Borealis Great Wall, a massive galactic filament stretching about 10 billion light-years across. It was identified through gamma-ray burst mapping. At this scale, even galaxy clusters are just dots on a web.
29. How long is a day on Venus compared to a year on Venus?
This fact breaks people’s brains in the best possible way.
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A day on Venus (one full rotation) is longer than a year on Venus (one orbit around the Sun). Venus takes about 243 Earth days to rotate once but only about 225 Earth days to orbit the Sun. It’s the only planet where this is true.
30. What percentage of the solar system’s total mass does the Sun account for?
People know the Sun is big. They don’t know it’s this big.
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About 99.86%. Everything else combined, every planet, moon, asteroid, comet, and grain of dust, accounts for roughly 0.14%. Jupiter makes up most of that remainder.
The Human Side of Space
31. Who was the first woman in space?
The gap between the most common answer and the correct answer tells you a lot about which space programs get remembered.
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Valentina Tereshkova, a Soviet cosmonaut, in 1963. The most common wrong answer is Sally Ride, who was the first American woman in space, but that wasn’t until 1983, twenty years later.
32. What was the first words spoken from the Moon’s surface?
Everyone knows “one small step.” That’s not what I asked.
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“Contact light.” Buzz Aldrin said it when the lunar module’s probes touched the surface, before the engine was shut down. The famous “one small step” line came later, when Armstrong actually stepped off the ladder. Most people conflate the landing with the first step.
33. Who was the first person in space?
This one’s a litmus test. If you know it instantly, you probably know more space history than average.
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Yuri Gagarin, a Soviet cosmonaut, on April 12, 1961. His flight aboard Vostok 1 lasted 108 minutes and completed one orbit. He was 27 years old.
34. What does NASA stand for?
Seems obvious until you have to actually spell it out. The second A trips people up.
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National Aeronautics and Space Administration. The stumble is almost always on “Aeronautics.” People say “Aerospace” or “Aviation” or just trail off after “Aero-something.”
35. Who was the last person to walk on the Moon?
Everyone knows the first. Almost nobody knows the last. That asymmetry says something about how we remember things.
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Eugene “Gene” Cernan, commander of Apollo 17, in December 1972. He passed away in 2017, still holding the title. Harrison Schmitt, the lunar module pilot on the same mission, was the second-to-last.
36. What was the name of the first artificial satellite launched into Earth orbit?
The beeping that changed everything.
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Sputnik 1, launched by the Soviet Union on October 4, 1957. It was about the size of a beach ball and transmitted radio pulses for 21 days before its batteries died. It burned up on reentry in January 1958.
37. How many times did the Space Shuttle Challenger fly successfully before its disaster?
Most people assume it was the shuttle’s first or second flight. The truth makes the loss feel different.
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Nine successful missions. Challenger had been to space and back nine times before the O-ring failure on January 28, 1986. It wasn’t an untested vehicle. That’s what made it so shocking.
38. Who was the first American to orbit the Earth?
There’s a trap here, and it catches people who know just enough to be dangerous.
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John Glenn, on February 20, 1962, aboard Friendship 7. The trap is Alan Shepard, who was the first American in space but on a suborbital flight. Shepard went up and came back down. Glenn went around.
39. What is the longest continuous time a human has spent in space?
The number is larger than most people guess, and it belongs to someone most people can’t name.
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437 days, by Russian cosmonaut Valeri Polyakov, aboard the Mir space station from January 1994 to March 1995. He reportedly walked off the spacecraft unassisted when he returned, partly to prove long-duration spaceflight was survivable.
40. What was the Challenger disaster’s cause?
Richard Feynman, a glass of ice water, and a rubber O-ring. One of the most famous demonstrations in the history of engineering.
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Failure of an O-ring seal in the right solid rocket booster, which allowed hot gases to escape and breach the external fuel tank. The O-rings lost their flexibility in the unusually cold temperatures on launch morning. Engineers at Morton Thiokol had warned against launching.
Light, Distance, and Numbers That Don’t Feel Real
41. What does a light-year measure?
I’ve asked this hundreds of times. A solid third of any room says time. Every single time.
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Distance. A light-year is the distance light travels in one year, about 5.88 trillion miles (9.46 trillion kilometers). The word “year” in the name is doing a lot of damage to people’s intuition.
42. How far away is the nearest galaxy to the Milky Way?
Depends on which galaxy you mean, and that’s where the interesting argument starts.
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The Canis Major Dwarf Galaxy is about 25,000 light-years from Earth, making it the closest known galaxy. But most people mean the nearest major galaxy, which is the Andromeda Galaxy at about 2.5 million light-years. If someone says Andromeda, I give them the point.
43. How old is the universe?
People are usually in the right ballpark but off by enough to matter at a trivia night.
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Approximately 13.8 billion years, based on observations of the cosmic microwave background radiation. The most common wrong guesses cluster around 10 billion or 15 billion.
44. What is the speed of light in miles per second?
Knowing it in kilometers is fine. Knowing it in miles is rarer. Getting within 10% feels like it should count.
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About 186,000 miles per second (roughly 300,000 kilometers per second). In one second, light could circle the Earth about 7.5 times.
45. What is the observable universe’s estimated diameter?
The number itself doesn’t land until you realize what “observable” means.
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About 93 billion light-years. This is larger than 13.8 billion light-years in every direction because the universe has been expanding the entire time. Light that left the earliest objects has been stretched by that expansion.
46. What is a parsec?
Han Solo used it wrong. Or did he? This one starts arguments between Star Wars fans and astronomers, which is a surprisingly specific Venn diagram.
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A unit of distance equal to about 3.26 light-years. It’s derived from “parallax of one arcsecond” and is based on the apparent shift of a star when viewed from opposite sides of Earth’s orbit. In the original Star Wars script, the “Kessel Run in less than twelve parsecs” was likely a mistake, but later canon retconned it into a distance-based boast about a shorter route.
47. What is the closest galaxy on a collision course with the Milky Way?
Don’t worry, you’ve got time.
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The Andromeda Galaxy, expected to merge with the Milky Way in about 4.5 billion years. The collision won’t be violent in the way you’d imagine. The space between stars is so vast that very few, if any, will actually collide. The galaxies will pass through each other and eventually merge into one elliptical galaxy, sometimes nicknamed “Milkomeda.”
48. What is redshift?
If you can explain this at a bar, you can explain anything at a bar.
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The stretching of light to longer (redder) wavelengths, typically caused by an object moving away from the observer or by the expansion of space itself. It’s how Edwin Hubble determined that distant galaxies were receding from us, leading to the discovery that the universe is expanding.
49. How many Earths could fit inside the Sun?
People guess thousands. They’re not wrong. They’re just not ambitious enough.
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About 1.3 million. The Sun’s volume is staggering. Its diameter is about 109 times Earth’s, and volume scales with the cube of the radius. Most people guess somewhere between 1,000 and 100,000.
50. What is the Kuiper Belt?
If you know where Pluto lives, you know more than you think.
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A region of the solar system beyond Neptune’s orbit, extending from about 30 to 50 AU from the Sun. It contains frozen bodies, dwarf planets including Pluto and Eris, and short-period comets. Think of it as the asteroid belt’s bigger, colder, more distant cousin.
Things That Orbit, Crash, and Explode
51. What is the difference between a meteor, a meteorite, and a meteoroid?
Location, location, location. This is the real estate question of space trivia.
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A meteoroid is a small rocky body in space. A meteor is what we call it when it enters Earth’s atmosphere and burns up (a “shooting star”). A meteorite is a piece that survives the journey and hits the ground. Same object, three names depending on where it is.
52. What caused the extinction of the dinosaurs, according to the leading scientific theory?
Everyone knows this one, but fewer people know where it hit.
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An asteroid impact, roughly 66 million years ago. The Chicxulub crater, buried beneath the Yucatán Peninsula in Mexico, is about 93 miles (150 km) wide. The asteroid itself was estimated at about 6 miles across.
53. What is a supernova?
Simple concept, but the details are where it gets beautiful.
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The explosive death of a star. Depending on the type, it occurs when a massive star exhausts its nuclear fuel and its core collapses, or when a white dwarf accumulates enough matter from a companion star to trigger runaway nuclear fusion. For a brief period, a supernova can outshine an entire galaxy.
54. What is the Oort Cloud?
Nobody’s ever seen it directly. We just know it has to be there.
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A theoretical spherical shell of icy bodies surrounding the solar system at a distance of roughly 2,000 to 100,000 AU from the Sun. It’s believed to be the source of long-period comets. No direct observations have confirmed it, but the orbits of those comets point back to this region.
55. What happens at the event horizon of a black hole?
The name gives it away if you think about it literally.
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It’s the boundary beyond which nothing, not even light, can escape the black hole’s gravitational pull. It’s not a physical surface. It’s a point of no return. From outside, you’d see objects falling in appear to slow down and redshift into invisibility as they approach it.
56. What is the asteroid belt located between?
This one’s a confidence builder. Let people have it.
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Mars and Jupiter. Despite how movies portray it, the asteroid belt is mostly empty space. If you flew through it, you’d be unlikely to see a single asteroid without deliberately aiming for one.
57. What is a pulsar?
When this answer lands right, it sounds like science fiction.
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A rapidly rotating neutron star that emits beams of electromagnetic radiation from its magnetic poles. As it spins, the beams sweep across space like a lighthouse. If one of those beams crosses Earth’s line of sight, we detect it as a regular pulse. Some rotate hundreds of times per second.
58. What was the name of the comet that spectacularly broke apart and crashed into Jupiter in 1994?
If you were alive for this, you remember the images. If you weren’t, you missed one of the great space events of the 20th century.
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Comet Shoemaker-Levy 9. It broke into 21 visible fragments that slammed into Jupiter over six days in July 1994. Some of the impact scars were larger than Earth. It was the first direct observation of an extraterrestrial collision in the solar system.
59. What type of star will our Sun eventually become?
The Sun’s future is surprisingly quiet for something so dramatic.
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A white dwarf. In about 5 billion years, the Sun will expand into a red giant, shed its outer layers into a planetary nebula, and leave behind a dense, cooling white dwarf core about the size of Earth. It won’t go supernova. It’s not massive enough.
60. What is the Chandrasekhar limit?
This is a question I save for tiebreakers. It separates people who like space from people who study it.
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Approximately 1.4 solar masses. It’s the maximum mass of a stable white dwarf star. Above this limit, electron degeneracy pressure can’t support the star against gravitational collapse, and it will either become a neutron star or trigger a Type Ia supernova. Named after Subrahmanyan Chandrasekhar, who calculated it at age 19.
Robots, Rovers, and the Machines We Sent Ahead
61. What are the names of the two Mars rovers that landed in 2004?
One of them was supposed to last 90 days. It lasted over 14 years.
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Spirit and Opportunity. Spirit got stuck in soft soil in 2009 and lost contact in 2010. Opportunity kept going until a global dust storm killed its solar panels in 2018. NASA’s last message attempt was met with silence. Opportunity’s final transmitted data essentially translated to “my battery is low and it’s getting dark,” which, yes, made the entire internet cry.
62. What was the first spacecraft to fly by all four outer planets?
A spacecraft that took advantage of a planetary alignment that happens once every 175 years.
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Voyager 2. It’s the only spacecraft to have visited Jupiter, Saturn, Uranus, and Neptune. Voyager 1 visited only Jupiter and Saturn before its trajectory was redirected for a close flyby of Titan.
63. What did the Hubble Space Telescope’s famous “Deep Field” image reveal?
Someone pointed a telescope at what looked like nothing and found everything.
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Thousands of galaxies in a tiny patch of sky that appeared nearly empty to ground-based telescopes. The original Hubble Deep Field, taken in 1995, covered an area of sky about the size of a grain of sand held at arm’s length. Nearly every object in the image is an entire galaxy. It fundamentally changed our understanding of how many galaxies exist.
64. What is the name of the Mars helicopter that achieved the first powered flight on another planet?
The Wright brothers brought a piece of their plane along for the ride. Literally.
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Ingenuity. It first flew on April 19, 2021, and far exceeded its planned five-flight mission, completing over 70 flights. It carried a small swatch of fabric from the Wright Flyer, the Wright brothers’ 1903 aircraft.
65. What is the James Webb Space Telescope’s primary mirror made of?
Gold gets the attention, but it’s not the mirror itself.
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Beryllium, coated with a thin layer of gold. The gold coating optimizes it for reflecting infrared light. Beryllium was chosen because it’s lightweight and holds its shape at extremely cold temperatures. Each of the 18 hexagonal segments is about the size of a coffee table.
66. What probe was the first to land on a comet?
It bounced. Twice. And still did science.
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Philae, the lander component of the European Space Agency’s Rosetta mission. It landed on Comet 67P/Churyumov-Gerasimenko in November 2014. Its harpoon anchoring system failed, and it bounced twice before settling in a shadowed area where its solar panels couldn’t charge properly.
67. What is the name of the NASA rover currently operating on Mars that launched in 2020?
Named by a student. Carries a piece of Martian history in its name.
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Perseverance. It landed in Jezero Crater in February 2021. Its primary mission includes searching for signs of ancient microbial life and caching rock samples for future return to Earth.
68. What was the first spacecraft to orbit another planet?
Not a rover. Not a flyby. An orbit. That distinction matters.
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Mariner 9, which entered orbit around Mars on November 14, 1971. It arrived during a massive global dust storm and had to wait weeks before it could photograph the surface. When the dust cleared, it sent back images of Olympus Mons, Valles Marineris, and the polar ice caps.
69. What is the Golden Record?
A mixtape for aliens. Curated by Carl Sagan’s committee. Still out there, still playing.
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A gold-plated copper phonograph record carried aboard both Voyager 1 and Voyager 2. It contains sounds and images selected to portray the diversity of life and culture on Earth, including music from Beethoven to Chuck Berry, greetings in 55 languages, and the brainwaves of a woman in love. It comes with a stylus and pictorial instructions for playback.
70. What space telescope, launched in 2009, was specifically designed to find Earth-sized exoplanets?
It found thousands of planets and changed the math on whether we’re alone.
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The Kepler Space Telescope. During its operational life, it discovered over 2,600 confirmed exoplanets and thousands more candidates. It worked by detecting tiny dips in a star’s brightness as a planet passed in front of it. It was retired in 2018 when it ran out of fuel.
The Questions That Start Arguments
71. Is Pluto a planet?
I’m not answering this one. I’m just telling you what the IAU says and letting you fight about it.
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According to the International Astronomical Union, no. Since 2006, Pluto has been classified as a dwarf planet because it hasn’t “cleared the neighborhood” around its orbit. But the debate is far from settled among planetary scientists, and the New Horizons mission in 2015 revealed Pluto to be far more geologically complex than anyone expected.
72. Can you hear sound in space?
The textbook answer is no. The real answer is more interesting.
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Sound as we know it, no. Space is a near-perfect vacuum, and sound waves need a medium to travel through. However, NASA has “sonified” data from various space phenomena, including translating pressure waves from a black hole in the Perseus galaxy cluster into audible sound. The waves are there. Our ears just can’t normally access them.
73. What happens to your blood in the vacuum of space?
Hollywood gets this wrong every time. Your blood does not boil out of your body.
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Your blood doesn’t boil because your circulatory system is a sealed pressurized system. Your skin and blood vessels contain the pressure. Exposed fluids on your tongue or in your eyes would boil (vaporize at low pressure), and you’d lose consciousness in about 15 seconds from lack of oxygen, but you wouldn’t explode. You’d have roughly 60-90 seconds before death.
74. Which came first: the Big Bang theory or the term “Big Bang”?
The name was coined by someone who didn’t even believe in it.
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The theory came first. Georges Lemaître proposed the expanding universe concept in 1927. The term “Big Bang” was coined by Fred Hoyle in a 1949 BBC radio broadcast. Hoyle actually favored the Steady State theory and used “Big Bang” somewhat dismissively. The name stuck anyway.
75. How much would a 150-pound person weigh on Mars?
People know Mars has less gravity. They rarely know how much less.
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About 57 pounds. Mars’s surface gravity is roughly 38% of Earth’s. This is one reason Mars is considered more feasible for human habitation than the Moon (which would make you weigh about 25 pounds) but still presents significant challenges for long-term bone and muscle health.
76. What is the cosmic microwave background radiation?
It was discovered by accident by two guys who thought they had a pigeon problem.
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The afterglow of the Big Bang, a faint radiation filling all of space that dates back to about 380,000 years after the universe began. Arno Penzias and Robert Wilson discovered it in 1965 while working at Bell Labs. They initially thought the persistent noise in their antenna was caused by pigeon droppings. They won the Nobel Prize.
77. What percentage of the universe is made up of ordinary matter?
This is the one that makes people question everything. We are a rounding error.
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About 5%. The rest is roughly 27% dark matter and 68% dark energy. Everything you can see, touch, and measure, every star, planet, gas cloud, and person, accounts for about one-twentieth of what’s out there. We don’t know what most of the universe is made of.
78. Has anything ever been born in space?
No human, but other species have managed it.
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No human has been born in space. However, various organisms have reproduced in space, including fish, frogs, and insects on various experiments aboard the Space Shuttle and ISS. Japanese medaka fish successfully mated and hatched in space in 1994.
79. What is the technical term for the point in an orbit closest to Earth?
This one sorts the space enthusiasts from the space nerds.
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Perigee. The farthest point is apogee. For orbits around the Sun, it’s perihelion and aphelion. For orbits around other bodies, the prefix changes: perijove for Jupiter, periareion for Mars, and so on.
80. What is Lagrange Point L2, and why is it important?
It’s where we park our most important telescopes, and the reason is elegant.
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L2 is a point in space about 1.5 million kilometers from Earth, directly away from the Sun. At this location, the gravitational pull of the Sun and Earth, combined with the centrifugal force of the orbit, allows a spacecraft to maintain a stable position relative to Earth while keeping the Sun, Earth, and Moon all behind it. The James Webb Space Telescope lives here, giving it an unobstructed view of deep space and a natural sunshield.
The Pop Culture Crossover
81. In the movie “The Martian,” what crop does Matt Damon’s character grow on Mars?
The botany joke that launched a thousand science discussions.
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Potatoes. He fertilizes Martian soil with human waste and uses water generated from hydrazine rocket fuel. The science in the movie is surprisingly accurate, with a few creative liberties. Andy Weir, who wrote the novel, did the math.
82. What real-life astronaut is portrayed by Ed Harris in “The Right Stuff” and also appears as a mission controller character in “Apollo 13”?
Ed Harris owns the space movie genre in a way nobody else does.
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John Glenn in “The Right Stuff” (1983). In “Apollo 13” (1995), Harris played Gene Kranz, the flight director, not an astronaut but a mission controller. Two different roles, both iconic, both space. Harris was also in “Gravity” as the voice of Houston.
83. What famous astronomer hosted the original “Cosmos” TV series in 1980?
“Billions and billions” was never actually his catchphrase, but everyone thinks it was.
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Carl Sagan. The series was watched by over 500 million people worldwide. Sagan never actually said “billions and billions” on the show, though he used the word “billions” frequently. He later used the phrase as the title of his final book, leaning into the joke.
84. What real NASA mission does the movie “Hidden Figures” center around?
The math that got John Glenn home, done by women whose names most people didn’t learn until 2016.
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John Glenn’s orbital flight on Friendship 7 in 1962. The film tells the story of Katherine Johnson, Dorothy Vaughan, and Mary Jackson, three Black women mathematicians at NASA whose calculations were essential to the mission’s success.
85. In Star Trek, what is the name of the propulsion system that allows faster-than-light travel?
A concept from science fiction that actual physicists have tried to make work.
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Warp drive. In 1994, physicist Miguel Alcubierre proposed a theoretical framework (the Alcubierre drive) that would compress space in front of a ship and expand it behind, technically moving the ship faster than light without violating relativity. It requires exotic matter with negative energy density, which may not exist. But the math works.
86. What was the first feature film shot partially in actual space?
This is recent enough that it catches people off guard.
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“The Challenge” (Vyzov), a Russian film. Actress Yulia Peresild and director Klim Shipenko traveled to the International Space Station in October 2021 and filmed scenes aboard the station. Tom Cruise has announced plans for a similar project, but the Russians got there first.
87. What does the “2001” in “2001: A Space Odyssey” refer to?
This feels like it should be obvious, but people always want it to mean something more.
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The year in which the film’s main story is set. Arthur C. Clarke and Stanley Kubrick chose it as a near-future date that felt plausible for interplanetary travel. The film was released in 1968. When the real 2001 arrived, we hadn’t sent anyone farther than the Moon, and we’d stopped doing even that.
88. What is the name of the fictional material in the movie “Avatar” that humans are mining on Pandora?
James Cameron named it with zero subtlety and I respect that.
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Unobtanium. It’s a tongue-in-cheek term that actually predates the movie, used in engineering and physics as a placeholder name for any material with impossible or ideal properties. Cameron used it straight-faced, which somehow works.
89. What does the Drake Equation attempt to estimate?
It’s less an equation and more a framework for organized speculation. But it changed how we talk about life in the universe.
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The number of active, communicative extraterrestrial civilizations in the Milky Way galaxy. Frank Drake formulated it in 1961. It multiplies several factors together, from the rate of star formation to the fraction of planets that develop intelligent life. Many of the variables are essentially guesses, but the equation gives the conversation a structure.
90. What real astronaut does Ryan Gosling portray in the 2018 film “First Man”?
The quietest man to do the loudest thing in human history.
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Neil Armstrong. The film focuses on the years leading up to the Apollo 11 mission, including the death of Armstrong’s young daughter and the Gemini 8 near-disaster. Gosling’s portrayal leaned into Armstrong’s famous reserve, which some audiences found cold and others found devastating.
The Deep Cuts
91. What is the name of the region on Mars that’s essentially a canyon system stretching over 2,500 miles?
It makes the Grand Canyon look like a crack in a sidewalk.
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Valles Marineris. It’s roughly 2,500 miles (4,000 km) long, up to 125 miles wide, and nearly 4.3 miles deep. For comparison, the Grand Canyon is about 277 miles long and just over a mile deep. Valles Marineris would stretch across the entire continental United States.
92. What is a magnetar?
The most magnetic objects in the known universe, and they make neutron stars look gentle.
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A type of neutron star with an extraordinarily powerful magnetic field, roughly a quadrillion times stronger than Earth’s. A magnetar’s field is strong enough to distort atomic orbitals and would be lethal from a distance of about 600 miles. They occasionally produce enormous gamma-ray flares. One such flare from SGR 1806-20 in 2004 was the brightest event ever observed from outside our solar system.
93. What was the first interstellar object detected passing through our solar system?
It looked wrong. It moved wrong. And we still don’t agree on what it was.
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‘Oumuamua, detected in October 2017. Its highly elongated shape, unusual acceleration, and hyperbolic orbit confirmed it came from outside our solar system. Avi Loeb of Harvard controversially suggested it could be an alien light sail. Most astronomers think it was a natural object, possibly a fragment of a nitrogen ice planet, but nobody’s entirely sure because it was already leaving by the time we spotted it.
94. What phenomenon causes astronauts to grow taller in space?
Come back from the ISS and your pants are too short. This is real.
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The absence of gravity allows the spinal discs to expand. Without the constant compression of Earth’s gravity, the vertebrae spread apart and astronauts can grow up to 2 inches (5 cm) taller. The effect reverses once they return to Earth. It can also cause back pain, which is less fun than it sounds.
95. What is the Fermi Paradox?
The question that keeps astrophysicists up at night and makes everyone else feel small.
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The apparent contradiction between the high probability of extraterrestrial civilizations existing (given the vast number of stars and planets) and the lack of evidence for, or contact with, such civilizations. Enrico Fermi supposedly posed it over lunch in 1950 with the simple question: “Where is everybody?” Dozens of proposed solutions exist, from the Great Filter to the Zoo Hypothesis, and none of them are particularly comforting.
96. What is spaghettification?
Yes, that’s the real scientific term. Yes, it means what you think it means.
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The vertical stretching and horizontal compression of objects into long, thin shapes in extremely strong gravitational fields, such as near black holes. The tidal forces are so extreme that the difference in gravitational pull between the near and far sides of an object stretches it out like spaghetti. The term was popularized by Stephen Hawking in “A Brief History of Time.”
97. What is the Wow! signal?
A 72-second radio signal from 1977 that has never been explained or repeated.
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A strong narrowband radio signal detected on August 15, 1977, by the Big Ear radio telescope at Ohio State University. Astronomer Jerry Ehman circled the signal’s alphanumeric sequence on the printout and wrote “Wow!” in the margin. It came from the direction of the constellation Sagittarius. Despite numerous attempts, it has never been detected again. Natural explanations have been proposed, including a hydrogen cloud from passing comets, but nothing has been definitively confirmed.
98. What did the LIGO observatory first directly detect in September 2015?
Einstein predicted them a century earlier. It took us that long to build a detector sensitive enough.
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Gravitational waves, caused by the merger of two black holes about 1.3 billion light-years away. The detection confirmed a major prediction of Einstein’s general theory of relativity. The signal lasted less than a second. LIGO detected a change in distance smaller than one-ten-thousandth the diameter of a proton.
99. What is the Kessler Syndrome?
This one matters more every year, and most people haven’t heard of it until they have.
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A theoretical scenario proposed by NASA scientist Donald Kessler in 1978, in which the density of objects in low Earth orbit becomes high enough that collisions between objects generate debris, which in turn causes more collisions, creating a cascading chain reaction. Eventually, certain orbital bands could become unusable. With tens of thousands of satellites now in orbit or planned, this isn’t theoretical anymore. It’s a ticking clock.
The Last One
100. What is the Pale Blue Dot?
I always end with this one. Not because it’s hard. Because of what it does to a room.
Show Answer
A photograph of Earth taken by Voyager 1 on February 14, 1990, from a distance of about 3.7 billion miles. In the image, Earth appears as a tiny speck, less than a pixel, suspended in a beam of scattered sunlight. Carl Sagan had requested that Voyager’s camera be turned around for one last look homeward before being shut off forever. He wrote about it afterward: “Look again at that dot. That’s here. That’s home. That’s us.” I’ve read that passage at the end of trivia nights and watched rooms go completely silent. Not because the question was hard. Because the answer made everything else we’d talked about feel different. That’s what the best space trivia does. It doesn’t just test what you know. It changes how you see where you are.
Science and nature rounds have a reputation for being the quizmasters' revenge. I write mine from Amsterdam, Netherlands with the opposite goal: questions where genuine curiosity gets rewarded. 7 years of writing them has convinced me that's possible. My rounds have been used by Quiz Night King, and I take the same care with every set I write.
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