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This Date in Science

This date in science: Sweden goes first to ban aerosol sprays

Ozone hole over Antarctica on September 11, 2014.  This is the date on which, NASA said, the hole reached its maximum extent for 2014.

Ozone hole over Antarctica on September 11, 2014. This is the date on which, NASA said, the hole reached its maximum extent for last year. NASA also said the 2014 ozone hole was holding steady in size, in comparison to other ozone holes in recent years. Image via NASA/Ozone Hole Watch.

January 23, 1978. On this date, Sweden announced it would ban aerosol sprays containing chlorofluorocarbons (CFCs) as the propelling agent. It was the first country in the world to do so. Scientific evidence had mounted that CFCs were damaging to Earth’s ozone layer. Sweden was the first to act on this evidence, which came before before the discovery of the Antarctic ozone hole. Virtually every country on Earth ultimately followed Sweden in banning CFCs, via an international treaty known as the Montreal Protocol. Follow the links inside to learn more, and to get an update on the most recent ozone hole over Antarctica.

This date in science: Near discovery of South Magnetic Pole

Explorers of the southern continent of Antarctica – Douglas Mawson, Alistair McKay and Edgeworth David – on January 16, 1909 at the South Magnetic Pole. Image via Wikipedia.

January 16, 1909. On this date, three members of an Ernest Shackleton expedition to Antarctica – Edgeworth David, Douglas Mawson and Alistair Mackay – raised a British flag and recorded the moment by photograph at what they thought was Earth’s South Magnetic Pole. It wasn’t until several years later that the team began to have doubts.

This date in science: Isaac Newton’s birthday

Photo via Flickr user Serhio

Photo via Flickr user Serhio

January 4, 1643. English physicist and mathematician Isaac Newton was born on this date. He is remembered as one of the world’s greatest scientists, because his insights laid a foundation for our understanding of celestial motion, light and gravity.

This date in science: Luna 1 spacecraft heads toward moon

Luna 1 was a milestone for exploration of the solar system, but American historians suspect the spacecraft failed one major objective: to hit the moon. Image credit: NASA

January 2, 1959. Trailing orange sodium gas, the Luna 1 spacecraft broke free of Earth’s gravity on this date, to head towards the moon.

This date in science: Earthrise from the moon

December 24, 1968. On this date, three astronauts had recently become the first human beings to leave our home planet and travel to another body in space. They all later said the most important thing they discovered was Earth. Today is the anniversary of the famous Apollo 8 “Earthrise” photograph captured by those astronauts. This video gives you a front row seat on the view seen by lunar astronauts in the Apollo 8 mission, as, during a roll maneuver of their craft, they peered from a window and noticed Earth ascending over the lunar horizon.

This date in science: Wright brothers’ first flight

The Wright brothers' airplane on its first powered flight on December 17, 1903.  Via Library of Congress.

The Wright brothers’ airplane on its first powered flight on December 17, 1903. Via Library of Congress.

December 17, 1903. On this date, two Ohio brothers – Wilbur and Orville Wright – made the first bonafide, manned, controlled, heavier-than-air flight. It was the first airplane, and it took off at 10:35 a.m. with Orville Wright on board as pilot. He flew their vehicle, called the Flyer, for 12 seconds over 120 feet (about 37 meters) of sandy ground just outside Kitty Hawk, North Carolina.

This date in science: Birthday of inventor of Dewey Decimal system

Photo credit: Elizabeth Howell

Melvil Dewey’s love of efficiency is clear in the Dewey Decimal System, which is used in libraries worldwide today. Photo credit: Elizabeth Howell

December 10, 1851. What if you wanted to organize every book in the library? That was the goal of Melvil Dewey, inventor of the Dewey Decimal classification system, used today in libraries around the world.

This date in science: Edwin Hubble and the expanding universe

This image is the Hubble eXtreme Deep Field, released in 2012.  Read more about this image here.

This is the Hubble eXtreme Deep Field, released in 2012. Nearly every speck of light here is a separate galaxy, beyond our Milky Way.

November 20, 1889. Happy birthday, Edwin Hubble! The Hubble Space Telescope is named for this astronomer. How did this honor come to be? Hubble’s work was pivotal in changing our entire cosmology: our idea of the universe as a whole.

This date in science: First radio signal beamed to space

Aerial view of Arecibo Observatory via Wiki Commons

The Arecibo Radio Telescope, at Arecibo, Puerto Rico, largest dish antenna in the world. In 1974, this telescope was used to broadcast the first intentional radio signal into space.

November 16, 1974. This is the anniversary of the most powerful broadcast ever deliberately beamed into space with the intention of contacting alien life. Some applauded this event as a mind-expanding attempt to remind people in 1974 that Earth is likely not the only planet where an intelligent civilization has evolved. At the time, others felt we shouldn’t be attempting to reveal Earth’s location in space to unknown alien civilizations.

This date in science: Launch of Sputnik

Photo credit: NASA

A replica of Sputnik 1, the first artificial satellite in the world to be put into outer space: the replica is stored in the National Air and Space Museum. Photo credit: NASA

October 4, 1957. On this date, the Soviet Union launched Sputnik I, the first artificial satellite to orbit the Earth. According to many space historians, the Space Age began on this date.