60 free Rainbow trivia questions with answers — science & nature quiz, new questions added Aug 2026.
53 free rainbow trivia questions with answers, mixing the physics of the bow with the stories people have told about it. The science half covers why a rainbow always sits opposite the Sun at about 42 degrees, why the secondary bow reverses its colours, what Alexander's band is, how moonbows and fogbows differ from the real thing, why Newton insisted on seven colours, and what a rainbow would look like on Saturn's moon Titan. The culture half ranges from Iris and Bifrost to the Rainbow Serpent, Noah's covenant and the leprechaun's pot of gold, then on to Gilbert Baker's 1978 pride flag, the Rainbow Warrior bombing, Rainbow Row in Charleston, Ritchie Blackmore's band, Reading Rainbow, Rainbow Road, Skittles and the song Judy Garland nearly lost from The Wizard of Oz. Every answer is checked against a cited encyclopaedia page. Difficulty runs from easy classroom facts to questions that will stump a pub quiz team, so it works for a school science unit, a Pride event or a family game night.
30 of 60 questions with answers and explanations. Play the quiz
Q 01A rainbow caused by sunlight always appears in which part of the sky?
Directly opposite the Sun
The centre of the arc lies on a line running from the Sun through the back of your head.
Q 02In a primary rainbow, which colour is on the outer edge of the arc?
Red
Red light leaves the raindrop at the widest angle, so it forms the outside of the bow.
Q 03At roughly what angle from the antisolar point does the primary rainbow appear?
42°
Light returned from a raindrop piles up at that turning-point angle, and it does not depend on the size of the drop.
Q 04Which three things happen to sunlight inside a raindrop to make a rainbow?
Refraction, internal reflection and dispersion
The light bends on entry, bounces off the back of the drop and bends again on the way out, splitting into colours.
Q 05Why are rainbows usually seen in the western sky in the morning?
The Sun is in the east and the bow sits opposite it
By early evening the geometry flips and the bow shows up in the east.
Q 06From where can a rainbow sometimes be seen as a complete circle?
An aeroplane
Every rainbow is really a circle; the ground simply hides its lower half from most observers.
Q 07Roughly how far outside the primary bow does the secondary rainbow of a double rainbow appear?
About 10°
It is caused by two reflections inside each drop, and its colours run in the reverse order.
Q 08What is the name for the strip of darker sky between a primary and a secondary rainbow?
Alexander's band
It honours Alexander of Aphrodisias, the Greek commentator who first described it around AD 200.
Q 09Why is a secondary rainbow always fainter than the primary?
More light escapes over two reflections and the bow is spread wider
In theory every rainbow is a double rainbow; the second bow is just often too weak to spot.
Q 10Isaac Newton originally split the spectrum into how many main colours before adding orange and indigo?
Five
He went up to seven partly to match the number of notes in a musical scale.
Q 11Newton settled on seven rainbow colours by analogy with what?
The notes of a musical scale
Scholars note that what he called 'blue' we would now call cyan, and his 'indigo' is closer to today's blue.
Q 12'Richard Of York Gave Battle In Vain' is a mnemonic for what?
The order of colours in a rainbow
It is said to recall Richard, Duke of York's death at the Battle of Wakefield in 1460, and shares its initials with 'Roy G. Biv'.
Q 13A rainbow made by moonlight rather than sunlight is called what?
A moonbow
Q 21Which medieval English friar first calculated the angular size of the rainbow, in his Opus Majus of 1268?
Roger Bacon
He stated the summit of a rainbow can never appear more than 42° above the horizon.
Q 22Which Song-dynasty Chinese polymath proposed that rainbows form when sunlight meets raindrops in the air?
Shen Kuo
His explanation, based on atmospheric refraction, is described as basically in line with modern science.
Q 23Whose 1637 Discourse on Method explained the rainbow with experiments on a water-filled glass sphere?
René Descartes
He also studied the effect using a Florence flask, having noticed drop size did not change the bow.
They are so dim that most people see them as white, because our colour vision is poor in low light.
Q 14Which waterfall on the Zambia–Zimbabwe border is famous for its spray moonbows?
Victoria Falls
In the US, Cumberland Falls in Kentucky and Yosemite are also known for them.
Q 15Why does a fog bow look almost white instead of coloured?
Its tiny droplets smear the colours by diffraction
Fog droplets are under 0.05 mm across; sailors sometimes call the result a sea-dog.
Q 16Sun dogs, the bright spots that flank the Sun, are caused by light passing through what?
Hexagonal ice crystals
The plate-shaped crystals act as prisms and bend light by a minimum of 22°, which is why the spots sit 22° either side of the Sun.
Q 17The circumhorizontal arc, or 'fire rainbow', appears only when the Sun is at least how high above the horizon?
58°
That makes it a rarity at high latitudes; it is a halo formed in ice crystals, not a true rainbow at all.
Q 18A rainbow on Saturn's moon Titan would have a radius of about 49° instead of 42°. Why?
Its rain is liquid methane, not water
Titan's hazy skies would make visible rainbows rare, but infrared ones might be common.
Q 19In what year was a third-order (tertiary) rainbow first definitively photographed in nature?
2011
Third- and fourth-order bows form on the Sun's side of the sky, so they are usually lost in the glare.
Q 20Which classical Greek scholar was the first to devote serious attention to explaining the rainbow?
Aristotle
His qualitative account was flawed but went unmatched for centuries; much later rainbow theory was a reaction to it.
Q 24In Greek mythology, which goddess personifies the rainbow and serves as messenger to the Olympians?
Iris
She was usually shown as a winged young woman with a herald's staff and a pitcher of water for the gods.
Q 25In Norse mythology, the burning rainbow bridge Bifrost connects Midgard to which realm?
Asgard
A god stands guard at its far end, and its red is said to be fire that keeps the frost giants from strolling into heaven.
Q 26Which Norse god lives at Himinbjörg and guards Bifrost from the giants?
Heimdall
The bridge is fated to break under the forces of Muspell during Ragnarök.
Q 27The Rainbow Serpent, a creator deity linked to water, comes from the mythology of which people?
Aboriginal Australians
A reliable waterhole is often regarded as the serpent's permanent home, and a rainbow is the serpent moving between them.
Q 28In the Book of Genesis, the rainbow is set as a token of God's promise after which event?
The great flood
An even older literary rainbow appears after a flood in the Epic of Gilgamesh.
Q 29Cuchavira, a rainbow god thanked with gold, snails and emeralds when the rains ended, belonged to which people?
The Muisca of Colombia
The offerings were made when the regular rains on the Bogotá savanna were over.
Q 30Which two-headed creature represents the rainbow in Chinese mythology?
A dragon called Hong
Rainbow deities elsewhere include Manzat in Mesopotamia and Anuenue, the rainbow maiden of Hawaiian legend.