Space trivia questions cover the solar system, the Moon, human spaceflight and the wider universe. The 30 below have verified answers and current 2026 figures, including August's total solar eclipse over Iceland and Spain, the Perseid meteor shower peak, and the Artemis II crewed lunar flyby. Six popular space facts that are false are corrected at the end.

August 2026 is an unusually good month to run a space round. A total solar eclipse crosses Iceland and northern Spain on 12 August, and the Perseid meteor shower peaks on the night of 12 to 13 August under a new moon. Questions 9 to 15 cover both, with the dates and durations you would need to actually go and watch them.

None of these 30 questions repeat the ones in the Space & Planets Trivia quiz, so you can play both without meeting the same answer twice.

Round 1: The solar system

1. Which planet is closest to Earth on average? Mercury, not Venus. Venus makes the closest single approach of any planet, but it spends much of its orbit on the far side of the Sun. Averaged over time, Mercury is nearer to Earth than Venus is, because it never strays far from the Sun. A 2019 analysis in Physics Today showed the same method makes Mercury the closest planet on average to every other planet in the solar system, including Neptune.

2. What is the largest moon in the solar system? Ganymede, which orbits Jupiter. At 5,268 km across it is larger than the planet Mercury, and it is the only moon known to generate its own magnetic field. Saturn's Titan is second. Both are bigger than any dwarf planet.

3. Which planet would float if you could find a bathtub big enough? Saturn. Its average density is about 0.69 grams per cubic centimetre, against 1.0 for water, because the planet is overwhelmingly hydrogen and helium spread across an enormous volume. It is the only planet in the solar system less dense than water.

4. How much of the solar system's mass is in the Sun? About 99.86 percent. Jupiter accounts for roughly two thirds of everything left over. All eight planets, every moon, the asteroid belt and every comet together make up less than a seventh of one percent of the total.

5. Which world has lakes and seas of liquid methane and ethane? Titan, Saturn's largest moon. It is the only place besides Earth known to have stable liquid on its surface, and it has a thick nitrogen atmosphere denser than our own. At about minus 179 degrees Celsius, water ice on Titan behaves like rock and methane fills the role water plays here, including rain and river channels.

6. What is the most volcanically active body in the solar system? Io, the innermost large moon of Jupiter, with more than 400 active volcanoes. The energy comes from tidal heating: Jupiter and the neighbouring moons Europa and Ganymede pull Io in different directions, flexing its interior and melting it from within. Some of its plumes reach 300 km above the surface.

7. How tall is Olympus Mons on Mars? About 22 km, roughly two and a half times the height of Everest above sea level, and around 600 km wide at the base. It is a shield volcano, so its slopes are gentle. Standing on it you would not perceive a mountain at all, because the summit lies beyond the horizon in every direction.

8. Which planet was found by mathematics before anyone looked for it? Neptune. Irregularities in the orbit of Uranus suggested an unseen mass beyond it, and Urbain Le Verrier calculated where that mass had to be. Johann Galle at the Berlin Observatory pointed a telescope at the predicted spot on 23 September 1846 and found the planet within one degree of it.

Round 2: The Moon, eclipses and meteor showers

9. When and where is the next total solar eclipse? 12 August 2026. The path of totality crosses northern Russia, Greenland, the west coast of Iceland, the North Atlantic, northern Spain and a small corner of Portugal. The greatest duration is 2 minutes and 18 seconds over the ocean about 45 km off western Iceland. In Spain the Sun is low, roughly an hour before sunset. Much of the northern United States, from Alaska to North Carolina, sees a partial eclipse only.

10. When did Spain and Iceland last see totality? Spain last saw a total solar eclipse on 30 August 1905, along a broadly similar track. Iceland last saw one on 30 June 1954, and after 2026 will not see another until 2196. That gap is why the 2026 event is drawing serious eclipse-chasing traffic to both countries.

11. When does the Perseid meteor shower peak in 2026? The night of 12 to 13 August 2026, with the peak predicted for about 14:53 UTC on 13 August. The shower is active from 17 July to 24 August. Conditions in 2026 are unusually good because the peak falls on a new moon, so there is no moonlight washing out fainter meteors, and observers under genuinely dark skies can expect up to roughly 100 meteors an hour.

12. Which comet produces the Perseids? Comet 109P/Swift-Tuttle, on a 133-year orbit. Its nucleus is about 26 km across, which makes it the largest object known to pass Earth repeatedly. It last reached perihelion in 1992 and returns in 2126. The meteors are debris shed on previous passes, spread along the comet's orbital path, which Earth ploughs through every August.

13. How fast do Perseid meteors hit the atmosphere? About 59 km per second, or 133,000 mph, which is the fastest of any major annual shower. Almost all of the particles producing those streaks are the size of a grain of sand. The brightness comes from the speed, not the size: the meteoroid compresses and heats the air ahead of it and burns up around 80 km overhead.

14. What is the difference between a meteoroid, a meteor and a meteorite? Location. A meteoroid is the rock while it is still in space. A meteor is the streak of light it makes burning through the atmosphere, so a meteor is an event rather than an object. A meteorite is the fragment that survives all the way to the ground, which for shower meteors essentially never happens.

15. Is the Moon getting closer to Earth or further away? Further, by about 3.8 cm a year. Tidal friction transfers rotational energy from Earth to the Moon's orbit, which also lengthens our day by roughly 1.7 milliseconds per century. The rate is measured by bouncing lasers off retroreflector arrays left on the surface by the Apollo crews and by Soviet Lunokhod rovers.

Round 3: Human spaceflight

16. Who was the first person in space? Yuri Gagarin, on 12 April 1961, aboard Vostok 1. The flight lasted 108 minutes and completed a single orbit. Gagarin ejected and parachuted down separately from the capsule, which the Soviet Union concealed for years because the rules of the day required a pilot to land inside the craft for the record to count.

17. Who was the first woman in space? Valentina Tereshkova, on 16 June 1963, aboard Vostok 6. She flew solo for almost three days and completed 48 orbits, more than every American astronaut up to that point combined. Twenty years passed before the second woman flew. Sally Ride became the first American woman in space in 1983.

18. How many people have walked on the Moon? Twelve, all of them between July 1969 and December 1972, across the six landing missions Apollo 11, 12, 14, 15, 16 and 17. Apollo 13 never landed. The last to step off the surface was Eugene Cernan on Apollo 17, which means nobody has walked there in over 50 years.

19. What did Artemis II achieve in 2026? It flew the first crewed mission around the Moon since Apollo. Artemis II launched on 1 April 2026 and splashed down in the Pacific on 10 April after 9 days, 1 hour and 32 minutes. The crew of Reid Wiseman, Victor Glover and Christina Koch of NASA and Jeremy Hansen of the Canadian Space Agency reached about 252,756 miles from Earth, beating the 248,655-mile record Apollo 13 set in 1970.

20. Where is the James Webb Space Telescope? Not in orbit around Earth. It sits near the second Sun-Earth Lagrange point, about 1.5 million km out on the far side of Earth from the Sun, so its tennis-court-sized sunshield can block the Sun, Earth and Moon at once. It launched on 25 December 2021. Nobody can service it there, which is why its deployment sequence had to work first time.

21. How far away is Voyager 1, and what does it reach in November 2026? About 15.8 billion miles and increasing. On 18 November 2026 it becomes the first human-made object one light-day from Earth, at a distance NASA has calculated as 16,094,799,096 miles, or 25,902,068,356 km. At that point a radio command sent from Earth takes a full 24 hours to reach it. Voyager 1 launched on 5 September 1977 and crossed into interstellar space in 2012.

22. What was the first animal to orbit Earth? Laika, a stray dog from Moscow, aboard Sputnik 2 on 3 November 1957. She was not the first animal in space, an honour that belongs to fruit flies carried on a US V-2 rocket in 1947. Soviet accounts claimed Laika survived several days. Russian scientists confirmed in 2002 that she died from overheating within hours of launch.

Round 4: Stars, galaxies and the universe

23. What colour is the Sun? White. It is classified as a yellow dwarf, but that label describes its class rather than its appearance. The Sun emits across the visible spectrum and its combined light is white, which is why sunlit snow looks white rather than cream. It appears yellow from the ground because the atmosphere scatters blue wavelengths out of the direct beam.

24. How old is the universe, and how wide is the part we can see? About 13.8 billion years old, and the observable universe is roughly 93 billion light-years across. Those numbers look contradictory until you account for expansion: the space between us and the most distant objects has stretched during the time their light spent travelling, so they are now far further away than the light's travel time suggests.

25. What is the oldest light anyone can detect? The cosmic microwave background, released about 380,000 years after the Big Bang. Before that the universe was an opaque plasma and light could not travel freely. When it cooled enough for atoms to form, that first light escaped, and it is still arriving from every direction as faint microwave radiation.

26. Will the Milky Way definitely collide with the Andromeda galaxy? No, and that answer changed recently. A study published in Nature Astronomy in June 2025, titled "No certainty of a Milky Way-Andromeda collision", ran 100,000 simulations using Hubble and Gaia data and 22 variables. It put the chance of a merger in the next 10 billion years at roughly 50 percent. The older figure of a certain collision in four to five billion years overstated what the data supports.

27. Is a light-year a measure of time or distance? Distance. One light-year is how far light travels in a year, about 9.46 trillion km or 5.88 trillion miles. The unit gets misused constantly in film dialogue, where characters describe journeys taking so many light-years. It is the interstellar equivalent of measuring a drive in kilometres rather than hours.

28. How big is the Milky Way? Roughly 100,000 light-years across, holding somewhere between 100 and 400 billion stars. The Sun sits about 26,000 light-years from the galactic centre, in a minor spiral arm, and takes around 230 million years to complete one orbit. The last time the Sun was in its current galactic position, dinosaurs were only starting to appear.

29. What is the most distant object visible to the naked eye? The Andromeda galaxy, about 2.5 million light-years away, visible from a dark site as a faint smudge in the autumn sky. The light reaching your eye left it before the genus Homo existed. It is also the largest object in our sky by apparent size, spanning several times the width of the full Moon.

30. Which planet has the fastest winds? Neptune, where winds have been clocked at around 2,100 km per hour, or 1,300 mph. That is faster than the speed of sound in Earth's atmosphere, and it happens on the planet that receives the least sunlight of the eight, which is one of the more stubborn open problems in planetary science.

Six space claims that are repeated constantly and are wrong

1. There is a dark side of the Moon. No. There is a far side, which is a different thing. The Moon is tidally locked, so it always shows Earth the same face, but every part of its surface gets sunlight across the lunar day. The far side is not permanently dark, it is permanently hidden from Earth. The Soviet probe Luna 3 photographed it in 1959 and the surface turned out to be paler than the near side, with far fewer of the dark volcanic plains.

2. The Great Wall of China is visible from space with the naked eye. Not with the naked eye. The wall is only a few metres wide in most places and is built from local materials that match the surrounding ground, so it has almost no contrast from orbit. Astronauts have said for decades that they cannot pick it out, and Yang Liwei, China's first astronaut, confirmed after his 2003 flight that he could not see it. Motorways and airports are far easier to spot.

3. Astronauts float because there is no gravity in space. Because they are falling, not because gravity has gone. At the International Space Station's altitude of about 400 km, Earth's gravity is still roughly 90 percent of its strength at the surface. The station is moving sideways fast enough that it keeps missing the planet as it falls, and everything inside falls with it. The proper term is microgravity, not zero gravity.

4. You would explode and your blood would boil in a vacuum. No. Skin and blood vessels hold the body together, and blood stays liquid because the circulatory system keeps it under pressure. The real hazard is oxygen loss: you would have roughly 15 seconds of useful consciousness. A NASA technician suffered a suit leak in a vacuum chamber in 1966, blacked out in about 14 seconds, and recovered with no lasting damage. His clearest memory was saliva boiling on his tongue.

5. Spacecraft have to dodge rocks crossing the asteroid belt. No. The belt contains a great many objects but is spread across a colossal volume, and neighbouring asteroids are typically separated by hundreds of thousands to millions of kilometres. Every probe sent to the outer solar system has crossed it without evasive manoeuvres. Getting a spacecraft close enough to photograph one takes deliberate targeting.

6. The Sun is a giant ball of fire. No, and it is not yellow either. Fire is combustion, a chemical reaction that needs oxygen. The Sun runs on nuclear fusion, squeezing hydrogen nuclei into helium under pressure at a core temperature near 15 million degrees Celsius. It converts roughly 4 million tonnes of mass into energy every second and has done so for about 4.6 billion years.

Where to take these questions next

For a quick scored round on the same material, the Space & Planets Trivia quiz runs ten multiple-choice questions with explanations. If you are building a wider science night, Ocean & Marine Life Trivia Quiz and How Well Do You Know the Human Body? cover the other two blocks most general-knowledge rounds draw on, and How Well Do You Know World Geography? works well as a closing round because almost everyone can answer some of it.

Frequently asked questions

When is the total solar eclipse in August 2026?

12 August 2026. The path of totality crosses northern Russia, Greenland, the west coast of Iceland, the North Atlantic, northern Spain and a small corner of Portugal. The greatest duration is 2 minutes and 18 seconds over the ocean about 45 km off western Iceland. In Spain the Sun is low, roughly an hour before sunset. Much of the northern United States, from Alaska to North Carolina, sees a partial eclipse only.

When does the Perseid meteor shower peak in 2026?

The night of 12 to 13 August 2026, with the peak predicted for about 14:53 UTC on 13 August. The shower is active from 17 July to 24 August. Conditions in 2026 are unusually good because the peak falls on a new moon, so there is no moonlight washing out fainter meteors, and observers under genuinely dark skies can expect up to roughly 100 meteors an hour.

Is there really a dark side of the Moon?

No. There is a far side, which is a different thing. The Moon is tidally locked, so it always shows Earth the same face, but every part of its surface gets sunlight across the lunar day. The far side is not permanently dark, it is permanently hidden from Earth. The Soviet probe Luna 3 photographed it in 1959 and the surface turned out to be paler than the near side, with far fewer of the dark volcanic plains.

Why do astronauts float if there is still gravity in space?

Because they are falling, not because gravity has gone. At the International Space Station's altitude of about 400 km, Earth's gravity is still roughly 90 percent of its strength at the surface. The station is moving sideways fast enough that it keeps missing the planet as it falls, and everything inside falls with it. The proper term is microgravity, not zero gravity.

Can you see the Great Wall of China from space?

Not with the naked eye. The wall is only a few metres wide in most places and is built from local materials that match the surrounding ground, so it has almost no contrast from orbit. Astronauts have said for decades that they cannot pick it out, and Yang Liwei, China's first astronaut, confirmed after his 2003 flight that he could not see it. Motorways and airports are far easier to spot.

How far away is Voyager 1?

About 15.8 billion miles and increasing. On 18 November 2026 it becomes the first human-made object one light-day from Earth, at a distance NASA has calculated as 16,094,799,096 miles, or 25,902,068,356 km. At that point a radio command sent from Earth takes a full 24 hours to reach it. Voyager 1 launched on 5 September 1977 and crossed into interstellar space in 2012.