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Today in science: Finding magnetic south

On January 16, 1909, a team of Antarctic explorers thought they’d found the magnetic south pole. Then, a few years later, they began to have doubts.

Today in science: Isaac Newton’s birthday

Isaac Newton was born on January 4, 1643. His insights laid a foundation for our modern understanding of celestial motion, light and gravity.

Today in science: 1st spacecraft to moon

Some historians believe Luna 1 – a Soviet spacecraft – was supposed to hit the moon. It didn’t but it was the first earthly craft to reach the moon, and sweep past.

Today in science: Wright brothers succeed

Check out one of the world’s most famous early photos. It shows the Wright brothers and the 1st true airplane on December 17, 1903.

Today in science: Edmond Halley

He’s the astronomer for whom Halley’s Comet is named. It was the first comet ever predicted to return.

Today in science: Launch of Sputnik

Sputnik’s unassuming beep ushered in the Space Age. Hear it here.

Today in science: E=mc2

Mass and energy are interchangeable.

Today in science: Earth from the moon

First photo of Earth from the moon, released it in 1966. Later, NASA used modern digital technology to restore the photo, revealing more detail.

Today in science: A moon for Mars

American astronomer Asaph Hall discovered Phobos, one of the two Martian moons, on this date in 1877. Did he imagine how well we’d see Mars’ moons today?

Today in science: 1st Mars landing

40th anniversary of the first fully successful soft landing on Mars’ surface, by the Viking 1 spacecraft. First images from Mars’ surface, here.

Today in science: 1st footsteps on moon

Today is the 47th anniversary of humanity’s historic first steps on the moon. The story in pictures, here.

Today in science: The day Earth smiled

Anniversary of 3rd-ever image of Earth from the outer solar system, acquired by the great Cassini spacecraft, as we Earth citizens cast our thoughts spaceward.

Today in science: The Tunguska explosion

On June 30, 1908, an explosion over Siberia killed reindeer and flattened trees. But no crater was ever found. It may have been a small asteroid.

Today in science: Egypt’s first meteorite

It was the first meteorite in the Egyptian record. Years after the event, scientists concluded through various tests that it came all the way from Mars.

Today in science: Kennedy’s moon speech

On May 25, 1961, President John F. Kennedy gave a stirring speech to a joint session of Congress declaring his intention to land humans on the moon with a decade.

Today in science: Neil Armstrong’s close call

On May 6, 1968 – more than a year before his famous first moonwalk – Neil Armstrong narrowly escaped disaster while training in the Lunar Landing Research Vehicle.

This date in science: Jan Oort’s birthday

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

The Southern Hemisphere has seen magnificent comets in recent years. But the last widely seen comet for the Northern Hemisphere was Hale-Bopp in 1996-97.

This date in science: Einstein’s birthday

While capping off the science of previous centuries, Albert Einstein changed our notions of space, time and matter … and launched modern physics.

This date in science: Yuri Gagarin’s birthday

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 …