48 Fun Facts About Edwin Hubble

Which Space Shuttle carried the telescope named after Edwin Hubble into orbit in April 1990?

Discovery released the Hubble Space Telescope in April 1990. It orbits above the atmosphere because moving air distorts starlight, the same effect that makes stars twinkle from the ground.

What does Hubble's 1929 finding that galaxies recede faster with distance imply about the universe?

It is expanding: the farther away a galaxy lies, the faster it recedes. Run that expansion backwards and everything starts out together, which is why Hubble's law became a pillar of the Big Bang theory.

Which pulsating stars, whose period-luminosity relation Henrietta Leavitt found, did Hubble use to measure distances?

Cepheid variables pulse with a period tied to their true luminosity, so comparing observed brightness with luminosity yields distance; Hubble found Cepheids in spiral nebulae with the Mount Wilson reflector.

In which US state was Edwin Hubble born in 1889, in the small town of Marshfield?

Missouri: Hubble was born in Marshfield in 1889. His father's job kept the family on the move, and Edwin finished his schooling in Illinois.

What did Hubble have fitted at home for his cat Nicolas Copernicus, saying cats need one 'for their self-respect'?

A cat door was duly made for the black cat. He had the run of the house, which came to be called 'Nicolas' estate'.

Which English novelist became a close friend of Edwin and Grace Hubble in California?

Aldous Huxley and his wife Maria grew close to the Hubbles in California. Fame had pulled the astronomer into Hollywood circles, where he mixed with film stars as well as writers.

For which university did Hubble play on a conference-champion basketball team?

Chicago: Hubble was on the university's 1909 championship basketball team. As a young man he was better known as an athlete than as a scholar, and he competed in track and field as well.

For which future Nobel-winning physicist did Hubble work as a student laboratory assistant?

Robert Millikan employed Hubble as a student laboratory assistant for a year. The two ended up in the same city: Millikan ran Caltech in Pasadena from 1921, where Hubble had his Mount Wilson office.

What did Hubble study at Oxford as a Rhodes Scholar, bowing to his father's wishes?

Jurisprudence, the theory of law, was his father's choice, and Hubble took his Oxford degree in it. He came home with an English accent and a pipe, habits he kept up in America.

Alongside physics and maths, which language did Hubble teach at New Albany High School in Indiana?

Spanish: Hubble had studied it at Oxford, and he taught it with physics and maths while coaching the school's basketball team. After a year he left the classroom for graduate school in astronomy.

Where did Hubble earn his 1917 PhD with a dissertation on faint nebulae?

Yerkes Observatory in Wisconsin was where Hubble photographed faint nebulae for his doctorate. When America entered the war in 1917 he rushed the thesis through, took his oral exam and reported for army duty three days later.

What rank did Hubble reach in the US Army's 86th Division during the First World War?

Hubble enlisted in 1917 after hurrying through his doctorate and rose to major in the 86th Division, which reached France in 1918 but was broken up for replacements and never fought.

Who offered Hubble a staff position at Mount Wilson Observatory in 1919?

George Ellery Hale first made the offer in 1917, then held the post open while Hubble went to war. Hubble headed straight for Mount Wilson when he got back to America in 1919.

Which instrument, then the world's largest of its kind, was newly completed when Hubble arrived at Mount Wilson?

The 100-inch Hooker Telescope began regular work just as Hubble arrived in 1919, and it stayed the world's largest for three decades. Its reach let him pick out single stars inside the spiral nebulae.

Hubble's variable-star distances, announced in 1924, showed which two nebulae to be separate galaxies?

Hubble's variable-star distances put the Andromeda and Triangulum nebulae (M31 and M33) nearly a million light-years away, far beyond any estimate of the Milky Way's size.

Who argued in the 1920 Great Debate that the spiral nebulae lay within the Milky Way?

Harlow Shapley argued in the 1920 debate with Heber Curtis that the spirals lay inside our own galaxy. When Hubble's letter arrived with the evidence against him, he reportedly called it the letter that 'destroyed my universe'.

In which newspaper were Hubble's findings on the nebulae first published, on November 23, 1924?

The New York Times carried the discovery on 23 November 1924, before any scientific journal. Astronomers got the formal version weeks later, in a paper read to their society's meeting on New Year's Day 1925.

Hubble's galaxy classification, with its two branches of spirals, is usually drawn as a diagram nicknamed after which object?

Tuning fork: elliptical galaxies run along the handle, then the diagram splits into two prongs, one for ordinary spirals and one for barred spirals like our own Milky Way.

Which objects did Hubble mistake for bright stars in far-off galaxies, making his distances too small?

Glowing gas clouds of hydrogen passed for single bright stars on his plates, so their galaxies seemed closer than they were. Hubble knew the risk, and his relative distances still held up.

Which two astronomers' redshift measurements did Hubble combine with his distances?

Vesto Slipher and Milton Humason supplied the speeds, Slipher having clocked the first nebular redshifts at Lowell Observatory. Humason had started at Mount Wilson as a mule driver and janitor before he became an observer.

Hubble's 1929 figures implied that the universe was only about how old?

2 billion years was the awkward answer, because radioactive dating already made the Earth's rocks older than that. The fault lay in his distances, which were several times too short.

Which Belgian priest-physicist predicted the redshift-distance law two years before Hubble?

Georges Lemaître derived the velocity–distance relation in a 1927 paper in a Belgian journal; a 2011 study by Mario Livio showed Lemaître himself trimmed the later English translation.

To avoid saying what the redshifts meant, which word did Hubble put before 'velocities' in a letter to de Sitter?

"Apparent" velocities was his phrase, chosen to stress what had been measured. What it meant, he told de Sitter, should be left to "the very few others who are competent to discuss the matter with authority".

What did Einstein reportedly call the cosmological constant he'd added to keep the universe static?

"The biggest blunder of my life" is how Einstein reportedly described the constant, in a remark passed on by George Gamow. After seeing Hubble's redshift data he dropped the term from his equations.

On his famous 1923 plate, Hubble wrote VAR! after crossing out his first label for which kind of object?

A nova was his first guess, marked N, until he saw that the star brightened and faded on a regular cycle. That rhythm gave its distance, which put the nebula around it far outside the Milky Way.

Which magazine put Edwin Hubble on its cover in February 1948?

Time ran his portrait on its cover of 9 February 1948. By then he was famous enough to mix with Hollywood film stars as easily as with astronomers.

Hubble never took to the word 'galaxies', so what did he title his 1936 book about them?

The Realm of the Nebulae grew out of lectures he gave at Yale in 1935. To the end he called galaxies 'extragalactic nebulae', so the old word went on the cover.

Which assistant of Hubble's carried on his cosmology programme after his death in 1953?

Allan Sandage was a graduate student working for Hubble in his last years. He took over the observing programme in 1953, saw his mentor's unfinished galaxy classification into print and spent decades refining the distances.

Hubble never fully accepted that redshifts meant galaxies were fleeing, so what did he suggest might cause them instead?

An unknown law of physics was the alternative Hubble kept open to the end of his life. His own galaxy counts seemed to fit a universe at rest better, and he would not rule out some principle nobody had yet recognised.

Where did Hubble spend the Second World War running ballistics research for the US Army?

Aberdeen Proving Ground, Maryland, was where the War Department sent him when he asked for active army service. He ran ballistics research and a supersonic wind tunnel there until 1946, and won a medal for it.

Which instrument did Hubble become the first astronomer to use, in January 1949?

The 200-inch Hale Telescope at Palomar took its first official photograph on 26 January 1949, with Hubble in the observing cage. He pointed it at an old friend: Hubble's Variable Nebula, whose changing brightness he had discovered.

Which pastime took Hubble to Rocky Mountain streams and to the River Test in England?

Fly fishing was his favourite escape, and he was a skilled hand with a dry fly. He was on a fishing holiday in the Rockies in July 1949 when he suffered the heart attack that cut back his observing.

Which institution in San Marino, California, holds Hubble's correspondence, notebooks and observing logs?

The Huntington Library had Hubble on its board of trustees from 1938 until he died, and it stood in his home town. His widow Grace left it his papers, and the diaries she kept went with them.

Which Royal Astronomical Society honour went to Hubble in 1940?

The Gold Medal is the top award the society can give, and Hubble's came in 1940. He travelled to England in 1953 to deliver its George Darwin Lecture, which became his last published paper: he died that September.

In 2008 the United States honoured Hubble and three other scientists by putting his face on what?

Postage stamp: the 41-cent American Scientists set of March 2008 also showed John Bardeen, Gerty Cori and Linus Pauling. All three were Nobel winners, which was the one honour Hubble chased and never got.

What flaw blurred the first images from the Hubble Space Telescope after its 1990 launch?

A misshapen main mirror was to blame: its outer edge had been ground too flat by a fraction of a hair's width. Astronauts fitted corrective optics in December 1993, much as glasses sharpen a blurry eye.

Besides the space telescope, which of these carries Edwin Hubble's name?

A crater on the Moon bears his name. By convention lunar craters honour scientists and explorers who made outstanding contributions, which is how so many astronomers ended up on the map there.

What kind of object is 1373 Cincinnati, which Hubble discovered from Mount Wilson in 1935?

An asteroid, and the only one credited to him: the man who measured the far galaxies found just one small rock close to home. It was named for the Cincinnati Observatory, whose staff worked out most of its orbit.

Which 18th-century philosopher hypothesised as early as 1755 that the nebulae were separate 'island' systems?

Immanuel Kant made the 'island universes' idea famous in a book of 1755, building on a suggestion the English astronomer Thomas Wright had made five years earlier. It stayed a guess until Hubble measured the distances in the 1920s.

Which English university did Hubble attend after the First World War to renew his astronomy studies?

Cambridge let him pick up astronomy again once the fighting stopped, while he was still a serving army officer. He got back to America in 1919 and went straight to California to start observing.

As a boy, Hubble loved the adventure novels of H. Rider Haggard and which French author?

Jules Verne and H. Rider Haggard were the young Hubble's favourite authors. At twelve he answered his grandfather's questions about Mars so well that the reply was printed in a newspaper.

The tall schoolboy Hubble set a 1906 Illinois state record in which track and field event?

High jump: the teenage Hubble set the Illinois state record in 1906. At a single school meet that year he won seven events and came third in another, and he kept up athletics at university and at Oxford.

Hubble came home from Oxford in 1913 to which Kentucky city on the Ohio River?

Louisville was where the Hubbles had settled while Edwin was abroad, and his father died early in 1913 before he got back. He found work close by, teaching at a high school over the state line in New Albany, Indiana.

By his own account, promoters urged the student Hubble to turn professional and fight which reigning heavyweight champion?

Jack Johnson was world champion while Hubble was boxing as a university heavyweight. The story may be polished, since he was known to embellish his past, but either way he chose a scholarship to Oxford over the ring.

What is unusual about Hubble's final resting place?

His wife never revealed it, and nobody has traced it since. There was no funeral either, apparently at his own wish, so the astronomer whose name went on a space telescope has no known grave.

The Hubble Space Telescope was due to launch in 1986, so which event kept it on the ground until 1990?

The loss of Challenger in 1986 grounded the whole shuttle fleet, and the telescope had to wait its turn. Engineers used the delay to run more tests and make upgrades, so a better machine flew in 1990.

Hubble wrote that 'the history of astronomy is a history of receding' what?

Horizons: the line comes from lectures he gave at Yale in 1935. It works twice over, since each new telescope pushed the edge of the known universe outwards, and his own galaxies turned out to be receding too.

Which tribute to Hubble stands beside the courthouse in his birthplace, Marshfield?

A replica space telescope stands on the courthouse lawn in Marshfield. Drivers get a reminder too: state law names the stretch of Interstate 44 through the surrounding county the Edwin P. Hubble Memorial Highway.