Alar Toomre
An astrophysicist who solved the mystery of galaxy structure, revealing how cosmic mergers create the majestic spirals we see.
Born 1937 (age 89)·American astronomer and mathematician·Birthday: February 5·The Silent Generation
Biography
Alar Toomre peered into the mathematics of chaos and saw the elegant dance of galaxies. At MIT, where he spent his academic career, he moved from fluid dynamics to tackling one of astronomy's big puzzles: why do so many galaxies have spiral arms? In a groundbreaking 1964 paper with his brother Jüri, he used mathematical modeling to show these arms were not static structures but density waves, like traffic jams moving through stars. Later, with groundbreaking computer simulations, he demonstrated how colossal mergers between galaxies could create the vast tidal tails and ripples observed in space. His work, blending profound insight with computational brute force, fundamentally changed how scientists understand galactic evolution and stability, earning him a MacArthur 'genius' grant for his transformative vision.
The Silent Generation
1928–1945
Born between the Depression and the end of WWII. Too young to fight, old enough to remember. They became the conformist middle managers of the 1950s — and the civil rights leaders who quietly dismantled Jim Crow.
Alar was born in 1937, placing them squarely in The Silent Generation. The events that shaped this generation — world wars, depression, and rapid industrialization — shaped the world they entered and the choices available to them.
#1 When Alar Was Born
The biggest hits of 1937
#1 Movie
Snow White and the Seven Dwarfs
Best Picture
The Life of Emile Zola
Alar's Life & Times
The world at every milestone
1937Born
Hindenburg disaster; Golden Gate Bridge opens
Gas: $0.20/galPresident: Franklin D. Roosevelt"A-Tisket, A-Tasket" — Ella FitzgeraldBest Picture: The Life of Emile Zola
1942Started school
Battle of Midway turns the tide in the Pacific
Gas: $0.20/galHome: $3,175Min wage: $0.30/hrPresident: Franklin D. Roosevelt"White Christmas" — Bing CrosbyBest Picture: Mrs. Miniver
1950Became a teenager
Korean War begins
Gas: $0.27/galHome: $7,354Min wage: $0.75/hrPresident: Harry S. Truman"Goodnight Irene" — Gordon Jenkins & The WeaversBest Picture: All About Eve
1953Could drive
DNA structure discovered by Watson and Crick
Gas: $0.27/galHome: $8,750Min wage: $0.75/hrPresident: Dwight D. Eisenhower"Song from Moulin Rouge" — Percy FaithBest Picture: From Here to Eternity
1955Could vote
Rosa Parks refuses to give up her bus seat
Gas: $0.29/galHome: $9,550Min wage: $0.75/hrPresident: Dwight D. Eisenhower"Rock Around the Clock" — Bill Haley & His CometsBest Picture: Marty
1958Turned 21
NASA founded
Gas: $0.31/galHome: $11,050Min wage: $1.00/hrPresident: Dwight D. Eisenhower"Volare" — Domenico ModugnoBest Picture: Gigi
1967Turned 30
Summer of Love in San Francisco; first Super Bowl
Gas: $0.33/galHome: $14,250Min wage: $1.40/hrPresident: Lyndon B. Johnson"To Sir, with Love" — LuluBest Picture: In the Heat of the Night
1977Turned 40
Star Wars premieres; Elvis dies
Gas: $0.62/galHome: $31,800Min wage: $2.30/hrPresident: Jimmy Carter"Tonight's the Night" — Rod StewartBest Picture: Annie Hall
1987Turned 50
Black Monday stock market crash
Gas: $0.90/galHome: $72,400Min wage: $3.35/hrPresident: Ronald Reagan"Walk Like an Egyptian" — The BanglesBest Picture: The Last Emperor
1997Turned 60
Princess Diana dies in Paris car crash; Harry Potter published
Gas: $1.23/galHome: $104,100Min wage: $5.15/hrPresident: Bill Clinton"Candle in the Wind 1997" — Elton JohnBest Picture: Titanic
2007Turned 70
iPhone released; Great Recession begins
Gas: $2.80/galHome: $172,600Min wage: $5.85/hrPresident: George W. Bush"Irreplaceable" — BeyonceBest Picture: No Country for Old Men
2017Turned 80
#MeToo movement; solar eclipse crosses the US
Gas: $2.42/galHome: $195,000Min wage: $7.25/hrPresident: Donald Trump"Shape of You" — Ed SheeranBest Picture: The Shape of Water
2026Age 89 today
Gas: $3.91/galPresident: Donald Trump
Key Achievements
- Co-authored the seminal density wave theory of spiral galaxies with his brother Jüri Toomre.
- Pioneered the use of computer simulations to model galactic collisions and their role in shaping galaxies.
- Awarded a MacArthur Fellowship in 1984 for his contributions to astrophysical dynamics.
- Mentored a generation of astrophysicists as a professor of applied mathematics at MIT for decades.
Did You Know?
He was born in Estonia and fled with his family during World War II, eventually settling in the United States.
His brother, Jüri Toomre, is also an accomplished astrophysicist and they collaborated on key research.
The 'Toomre sequence' is a classification of galaxy mergers named for his and Jüri's work.
He is known for his incredibly detailed and artistic hand-drawn diagrams explaining complex dynamical concepts.
“Galaxies are not static; their spiral arms are density waves in a rotating disk.”
