This eclipse trivia quiz has 50 free questions with answers and covers both kinds: the solar eclipse, when the Moon blots out the Sun for a few precious minutes along a narrow path, and the lunar eclipse, when the Moon slides into Earth's shadow and turns red for anyone on the night side of the planet. It explains why the two bodies happen to look the same size, how long totality can last, why the corona only shows itself then, and what Baily's beads and the diamond ring are. It also covers eclipse history and culture: the battle Herodotus says was stopped by a darkened sky, the 1919 eclipse that made Einstein famous, Columbus's trick in Jamaica, the Concorde that flew inside the Moon's shadow, the Great American Eclipse of 2017 and the 2024 eclipse across Mexico, the US and Canada, plus a nod to Bonnie Tyler and Twilight. Difficulty runs from easy to expert. Every answer has been checked against a primary reference and each question carries its citation.
30 of 50 questions with answers and explanations. Play the quiz
Q 01The Sun's diameter is 400 times the Moon's. By what factor is the Sun farther from Earth, which is why the two look the same size in our sky?
400
That coincidence gives both bodies an apparent size of about half a degree, so the Moon can just cover the Sun's disk.
Q 02What is the theoretical maximum length of totality during a solar eclipse?
7 min 32 s
The longest one between 3000 BC and 8000 AD comes on July 16, 2186 and will run 7 min 29 s.
Q 03In which kind of solar eclipse does the Moon appear too small to cover the Sun, leaving a bright ring?
Annular
It happens when the Moon is near the far point of its orbit. A hybrid eclipse shifts between annular and total along its path.
Q 04What is the name of the dark central part of the Moon's shadow, inside which a total eclipse is seen?
Umbra
It is typically only 100-160 km wide on the ground, while the penumbra, where the eclipse is partial, spans more than 6,400 km.
Q 05Which part of the Sun becomes visible to the naked eye only during a total eclipse?
The corona
It is the outer atmosphere, normally drowned out by the far brighter photosphere.
Q 06How often, on average, does a total solar eclipse happen somewhere on Earth?
Every 18 months
But any single spot on the planet waits an average of 360-410 years between total eclipses, which is why people travel for them.
Q 07How many solar eclipses of any kind occur in a typical year?
Between two and five
There is at least one in every eclipse season, and partial eclipses come along about twice a year.
Q 08What is the name of the roughly 18-year cycle after which a near-identical eclipse repeats?
Saros
It lasts 6,585.3 days. Each series begins with a partial eclipse near one of the poles and drifts across the globe over centuries.
Q 09What are Baily's beads, seen just before and after totality?
Sunlight shining through valleys on the Moon's edge
Francis Baily explained them in 1836, though Edmond Halley had recorded them during the eclipse of 1715. When just one bead is left you get the diamond ring.
Q 10Which astronomer made the first recorded observation of Baily's beads, during the eclipse of 3 May 1715?
Edmond Halley
He is better known for the comet, but he also produced one of the first accurate eclipse-path maps for that same 1715 event.
Q 11Which theory did Arthur Eddington's observations of the total eclipse of May 29, 1919 help confirm?
General relativity
He measured how much the Sun's gravity shifted the apparent positions of stars in Taurus, and the result made Einstein a global celebrity.
Q 12Per Herodotus, a 585 BC eclipse halted a battle between the Medes and which other people?
The Lydians
Thales of Miletus is said to have predicted it, though modern historians doubt he could have. Isaac Asimov called it the earliest event whose date is known to the day.
Q 13A clay tablet recording an early solar eclipse was found at Ugarit, in which modern country?
Syria
Q 21What is a selenelion?
Seeing the Sun and the eclipsed Moon at the same time
It is possible near sunrise or sunset because refraction lifts both bodies above the horizon, and works best from a mountaintop.
Q 22According to Maya and Inca tradition, which animal was devouring the Moon during a lunar eclipse?
A jaguar
Cultures around the world explained eclipses as something eating the Sun or Moon; in China it was a dragon.
Q 23How many lunar eclipses will there be in the 21st century in total?
228
That works out to about 2.28 a year. Roughly a third of all lunar eclipses are the barely noticeable penumbral kind.
Two dates are usually proposed for it: 3 May 1375 BC or 5 March 1223 BC. Chinese astronomers were predicting eclipses by the 4th century BC.
Q 14Why will total solar eclipses eventually stop happening?
The Moon is slowly drifting farther away
Estimates for when the Moon will be too distant to cover the whole Sun range from 650 million to 1.4 billion years from now.
Q 15When is it safe to look at a solar eclipse without a certified solar filter?
Only during the brief period of totality
Even a few seconds of looking at the photosphere can permanently damage the retina, and it is no safer during an eclipse than on any other day.
Q 16At which lunar phase can a lunar eclipse occur?
Full
Earth has to sit between the Sun and Moon, and that only happens at full moon during an eclipse season.
Q 17Why does the Moon turn red rather than black during a total lunar eclipse?
Sunlight is refracted through Earth's atmosphere
Rayleigh scattering strips out the blues, so what reaches the Moon is the light of every sunrise and sunset on Earth at once. Without an atmosphere the Moon would go completely dark.
Q 18Roughly how long can the total phase of a lunar eclipse last?
Nearly 107 minutes
From first to last contact with Earth's shadow the whole event can stretch to 236 minutes, and unlike a solar eclipse it can be seen from the entire night side of the planet.
Q 19Do you need eye protection to watch a lunar eclipse?
No, it is safe to view with the naked eye
You are looking at the Moon lit by dim, refracted sunlight, not at the Sun itself.
Q 20Which five-step scale, from L=0 to L=4, rates how dark a total lunar eclipse looks?
Danjon scale
L=0 is a Moon that is almost invisible; L=4 is a bright copper-red. Volcanic ash in the atmosphere can push an eclipse toward the dark end.
Q 24On which island did Columbus use a predicted lunar eclipse in 1504 to frighten locals into feeding his crew?
Jamaica
He told the cacique that God was angry with them; when the Moon darkened on cue, the provisions resumed. Columbus credited Abraham Zacuto's almanac.
Q 25The 2017 'Great American Eclipse' was the first coast-to-coast US total eclipse since which year?
1918
Its path ran from Oregon to South Carolina across 14 states, and it was the first eclipse since 1776 whose path of totality touched no other country.
Q 26Near which Illinois city did the 2017 eclipse reach its longest totality, about 2 minutes 41 seconds?
Carbondale
Carbondale scored again in 2024, sitting near the crossing point of both eclipse paths.
Q 27How many US states did the path of totality cross during the 2017 eclipse?
14
Totality first touched land on the Oregon coast at 10:16 a.m. Pacific time.
Q 28Near which Mexican town did the April 8, 2024 eclipse reach its maximum totality of 4 minutes 28 seconds?
Nazas, Durango
Totality was visible from six Mexican states, fifteen US states and six Canadian provinces, the first eclipse to cross all three countries this century.
Q 29How many US states saw totality during the April 8, 2024 eclipse?
15
An estimated 50 million people were in or travelled into the path, which was about 198 km wide.
Q 30After 2024, in which year will the next total solar eclipse touch the contiguous United States?
2044
That one, on August 22, 2044, clips only Montana and the Dakotas; a much bigger coast-to-coast eclipse follows in August 2045.