50 free Edwin Hubble trivia questions with answers — science & nature quiz, new questions added Aug 2026.
Edwin Hubble was a high-school track star and Big Ten basketball champion who studied law at Oxford to please his dying father, then went to Mount Wilson and proved the universe was vastly bigger than the Milky Way. In 1929 he showed that galaxies recede faster the farther away they are, the observation that made Einstein abandon his "biggest blunder". This quiz is about the astronomer, not the space telescope, though the telescope gets a question too. Easy questions ask what he proved about the nebulae, which telescope carries his name and which law bears it. Harder ones want the star type he used as a yardstick, the Harvard rival who opposed him, the newspaper that broke his discovery, his wildly wrong value for the constant, the Belgian priest who got there first, the wartime job that earned him a Legion of Merit, the comet and asteroid he found, why he never got a Nobel Prize and where he is buried, which nobody knows. Every answer was checked against Wikipedia's biography of Edwin Hubble, and each question carries the sentence that supports it. Made for astronomy teachers, students and quiz hosts. Related quizzes: Hubble Space Telescope, Astronomy and Famous Physicists.
30 of 50 questions with answers and explanations. Play the quiz
Q 01What did Hubble prove about many objects that had been classified as "nebulae"?
They were galaxies beyond the Milky Way
Before his 1924 observations, the prevailing view was that the universe consisted entirely of the Milky Way.
Q 02What does Hubble's 1929 finding that galaxies recede faster with distance imply about the universe?
It is expanding
The relation became known as Hubble's law, though Georges Lemaître had proposed it two years earlier.
Q 03Which pulsating stars, whose period-luminosity relation Henrietta Leavitt found, did Hubble use to measure distances?
Cepheid variables
Comparing their apparent brightness to their intrinsic brightness gives their distance, making them a "standard candle".
Q 04In which Missouri town, home to a model of the space telescope, was Hubble born in 1889?
Marshfield
The stretch of Interstate 44 through the town is called the Edwin Hubble Highway.
Q 05What was the profession of Hubble's father, John Powell Hubble?
Insurance executive
The family moved to Wheaton, Illinois, in 1900 and later to Kentucky.
Q 06What was the only school subject in which the young Hubble did not earn good grades?
Spelling
He was better known for athletics than brains, playing baseball, football and running track.
Q 07Which college's basketball team did Hubble lead to its first Big Ten Conference title in 1907?
Chicago
He also won seven first places and a third in a single high-school track meet in 1906.
Q 08For which future Nobel-winning physicist did Hubble work as a student laboratory assistant?
Robert Millikan
He took a Bachelor of Science in mathematics, astronomy and philosophy in 1910.
Q 09What did Hubble study at Oxford as a Rhodes Scholar, keeping a promise to his dying father?
Jurisprudence
He later added literature and Spanish and took a master's degree, but never had the motivation to practise law.
Q 10What did Hubble do for a year at New Albany High School in Indiana after returning from Oxford?
Taught Spanish, physics and maths and coached basketball
He was inducted into the Indiana Basketball Hall of Fame in 2017.
Q 11Where did Hubble earn his 1921 PhD with a dissertation on faint nebulae?
Yerkes Observatory
It gave him access to George Ellery Hale's 40-inch refractor, built in 1897.
Q 12What rank did Hubble reach in the US Army's 86th Division during the First World War?
Major
He rushed to finish his PhD to enlist, but the division was broken up for replacements and never saw combat.
Q 13Who offered Hubble a staff position at Mount Wilson Observatory in 1919?
George Ellery Hale
The observatory's founder and director had also built the 40-inch refractor Hubble used at Yerkes.
Q 21What value did Hubble's measurements on 46 galaxies give for the Hubble constant?
500 km/s/Mpc
The accepted figures today are around 74 (distance ladder) or 68 (cosmic microwave background); his errors came from distance calibration.
Q 22Which Belgian priest-physicist predicted the redshift-distance law two years before Hubble?
Georges Lemaître
A 2011 letter found by Mario Livio showed the priest himself trimmed the English translation of his 1927 paper.
Q 23Which word did Hubble use for the galaxies' velocities in a 1931 letter to de Sitter, stressing empiricism?
"Apparent"
He left the interpretation to "the very few others who are competent", and to the end favoured keeping open a model with no true expansion.
Q 14Which instrument, then the world's largest of its kind, was newly completed when Hubble arrived at Mount Wilson?
The 100-inch Hooker Telescope
With it he found Cepheids in the Andromeda and Triangulum nebulae.
Q 15Which two nebulae did Hubble's 1924 Cepheid observations prove were separate galaxies?
Andromeda and Triangulum
The finding had been hypothesised as early as 1755 by Immanuel Kant.
Q 16Which Harvard astronomer led opposition to Hubble's claim that nebulae lay outside the Milky Way?
Harlow Shapley
Some renowned colleagues simply scoffed, but Hubble published anyway.
Q 17In which newspaper were Hubble's findings on the nebulae first published, on November 23, 1924?
The New York Times
He presented them to the American Astronomical Society on New Year's Day 1925; the peer-reviewed paper on Andromeda came in 1929.
Q 18What is the astronomer's system for classifying galaxies by their photographic appearance called?
The Hubble sequence
It is still the most commonly used scheme, often drawn as a tuning fork.
Q 19By roughly what factor were Hubble's estimated galaxy distances later found to be too small?
Up to about 7
He was confused by two kinds of Cepheids and by bright gas clouds mistaken for stars, but the proportions held.
Q 20Which two astronomers' redshift measurements did Hubble combine with his distances?
Vesto Slipher and Milton Humason
Slipher had provided the first evidence a decade earlier that the nebulae's light was strongly redshifted.
Q 24What did Einstein later call the cosmological constant he'd added to keep the universe static?
"The biggest blunder of my life"
When he learned of Hubble's redshifts, he accepted that the expansion his equations predicted must be real.
Q 25In which year did Einstein visit Mount Wilson, meet Hubble and say the visit 'changed his mind'?
1931
The visit sealed Einstein's acceptance of an expanding universe.
Q 26Which asteroid did Hubble discover on August 30, 1935?
1373 Cincinnati
Asteroid 2069 Hubble was later named in his honour, as was a crater on the Moon.
Q 27What was the title of Hubble's 1936 book explaining his approach to extragalactic astronomy?
The Realm of the Nebulae
The same year he wrote The Observational Approach to Cosmology.
Q 28For how many days did the comet Hubble discovered on 4 August 1937, C/1937 P1, remain observable?
58
It was last seen on 28 October that year.
Q 29What did Hubble surprisingly tell the AAAS in December 1941 that a six-year Mount Wilson survey showed?
The results did not support the expanding universe
His own constant would have made the Big Bang only 2 billion years old, younger than the Earth.
Q 30Where did Hubble work as a civilian during the Second World War, heading the External Ballistics Branch?
Aberdeen Proving Ground, Maryland
He developed a high-speed clock camera for studying bombs in flight and received the Legion of Merit in 1946.