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This Date in Science

This date in science: Kennedy ignites dreams of moon

May 25, 1961. On this date, President John F. Kennedy gave a stirring speech before a joint session of Congress, in which he declared his intention to focus U.S. efforts on landing humans on the moon within a decade. His words ignited the work of a decade, in achieving the dream of a moon landing. Among other things, he said:

I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the Earth.

Full text of Kennedy’s speech inside.

This date in science: Neil Armstrong’s close call

May 6, 1968. More than a year before he became the first human to set foot on the moon, Neil Armstrong had a narrow escape in the Lunar Landing Research Vehicle (LLRV) at Ellington Air Force Base near Houston. The LLRV had been designed to simulate a descent to the moon’s surface, and all the lunar astronauts trained in it. That day, while Armstrong was piloting, a leaking propellant caused a total failure of his flight controls …

This date in science: Jan Oort’s birthday

Jan Oort. Copyright Leiden Observatory. Used with permission.

Jan Oort. Copyright Leiden Observatory. Used with permission.

Visualize a vast reservoir of icy comets on the outskirts of our solar system. That’s what Jan Oort did in 1950, and why the Oort Cloud bears his name.

This date in science: Comet Hale-Bopp

Comet Hale-Bopp with its prominent dust (white) and plasma (blue) tails. Photo via E. Kolmhofer, H. Raab; Johannes-Kepler-Observatory, Linz, Austria.

Comet Hale-Bopp with its prominent dust (white) and plasma (blue) tails. Photo via E. Kolmhofer, H. Raab; Johannes-Kepler-Observatory, Linz, Austria.

April 1, 1997. On this date, Comet Hale-Bopp – probably the best-remembered bright comet for many in the Northern Hemisphere – reached its perihelion or closest point to the sun.

This date in science: Einstein’s birthday

Albert Einstein in 1947, via Wikimedia Commons

Albert Einstein in 1947, via Wikimedia Commons

Albert Einstein was born on March 14, 1879. He published his Special Theory of Relativity in 1905 and his General Theory of Relativity in 1916. His work capped off the work of several previous centuries of science … and launched modern physics.

This date in science: Yuri Gagarin’s birthday

“Let’s go! (Poyekhali!)” Image via ESA.

He was a Russian Soviet pilot and the first human to travel to space, in 1961. Later, he became one of the world’s true heroes …

This date in science: Closest supernova since 1604

Supernova SN 1987A, one of the brightest stellar explosions since the invention of the telescope more than 400 years ago, is no stranger to the NASA/ESA Hubble Space Telescope. The observatory has been on the frontline of studies into this brilliant dying star since its launch in 1990, three years after the supernova exploded.  Image via spacetelescope.org

Supernova SN 1987A, one of the brightest stellar explosions since the invention of the telescope more than 400 years ago.

February 24, 1987. When Supernova 1987A first appeared in earthly skies – during the night of February 23-24, 1987 – astronomers were beside themselves with delight. It was the closest observed supernova since 1604. In this shining pinpoint in our sky, those fortunate to be in Earth’s Southern Hemisphere (in whose sky the supernova appeared) could see the death throes of a giant star. The new star remained visible to the eye for many months. It has been studied by astronomers for decades since. Follow the links inside to learn more about Supernova 1987A.

This date in science: John Glenn first American to orbit Earth

John Glenn and Friendship 7

John Glenn and Friendship 7

February 20, 1962: John Glenn became the first American to orbit the Earth. He made three turns around the planet before returning safely in his spacecraft, Friendship 7.

This date in science: Happy birthday, Nicolaus Copernicus

This Flammarion engraving, by an unknown artist, is called Empedocles Breaks through the Crystal Spheres. Its original caption read: “A missionary of the Middle Ages tells that he had found the point where the sky and the Earth touch…”

February 19, 1473. Nicolaus Copernicus was born on this date, 541 years ago. Copernicus was a Renaissance astronomer and mathematician. He lived at a time when people believed Earth lay enclosed within crystal spheres at the center of the universe. Can you picture the leap of imagination required for him to conceive of a sun-centered universe? The publication of Copernicus’ book – De revolutionibus orbium coelestium (On the Revolutions of the Celestial Spheres) – just before his death in 1543, set the stage for all of modern astronomy. Today, people speak of his work as the Copernican Revolution.

This date in science: Galileo’s birthday

Portrait, attributed to Murillo, of Galileo gazing at the words 'E pur si muove' (not legible in this image) scratched on the wall of his prison cell. Image via Wikimedia Commons.

Portrait, attributed to Murillo, of Galileo gazing at the words ‘E pur si muove’ – ‘and yet it moves’ (not legible in this image) – scratched on the wall of his prison cell. Image via Wikimedia Commons.

February 15, 1564. Italian astronomer, mathematician, and physicist Galileo Galilei was born 452 years ago today. He is one of the first people on Earth to have aimed a telescope at the heavens. His discovery of Jupiter’s moons (among other things) showed Earth was not the center of the universe and was considered heresy by the Roman Inquisition. In 1633, the Inquisition forced Galileo to recant.