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This Date in Science

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.

This date in science: E=mc2

Image credit: Wikimedia Commons

Albert Einstein in 1905, his “miracle year.” Image via Wikimedia Commons

September 27, 1905. On this date, while he was employed at a patent office, Albert Einstein published a paper titled “Does the Inertia of a Body Depend Upon Its Energy-Content?” It was the last of four papers he submitted that year to the journal Annalen der Physik. The first explained the photoelectric effect, the second offered experimental proof of the existence of atoms, and the third introduced the theory of special relativity. In the fourth paper, Einstein explained the relationship between energy and mass. That is, E=mc2

A first glimpse of Earth and moon as worlds in space

Here is the first-ever photo of the Earth and moon in a single frame.  Voyager 1 took the photo on September 18, 1977, when it was 7.25 million miles (11.66 million kilometers) from Earth.   Image Number: P-19891 via NASA/JPL

Here is the first-ever photo of the Earth and moon in a single frame. Voyager 1 took the photo on September 18, 1977, when it was 7.25 million miles (11.66 million kilometers) from Earth. Via NASA/JPL

September 18, 1977. Previous images had shown a part of the Earth, and a part of the moon, together. But – until this image by Voyager 1, taken on today’s date 37 years ago – we had never seen the Earth and moon as whole worlds in space, in the same frame and in color.

This date in science: Pioneer 11 swept past Saturn

Image credit:  NASA/Ames

Image credit: NASA/Ames

September 1, 1979. On this date, NASA’s Pioneer 11 came within 13,000 miles (21,000 kilometers) of Saturn, making it the first spacecraft ever to sweep closely past that place. The spacecraft found a new ring for Saturn – now called the “F” ring – and also a new moon, Epimetheus. There were two Pioneer spacecraft. They were used to investigate Saturn’s rings and determine if a trajectory through the rings was safe for the upcoming Voyager visits. They paved the way for the even-more-sophisticated Voyager spacecraft, which were launched in 1977.

Back to the future with Neptune’s fascinating moon Triton

Neptune and Triton, via Voyager 2.

Neptune and Triton, via Voyager 2.

On the anniversary of Voyager 2’s encounter with Neptune and Triton … an awesome collection of restored Voyager 2 images, plus the link between Triton and Pluto.

This date in science: First view of Earth from the moon

Photograph courtesy NASA/Lunar Orbiter 1 This photo reveals the first view of Earth from the moon, taken by Lunar Orbiter 1 on August 23, 1966. Shot from a distance of about 236,000 miles (380,000 kilometers), this image shows half of Earth, from Istanbul to Cape Town and areas east, shrouded in night.

First view of Earth from the moon, courtesy NASA/Lunar Orbiter 1.

August 23, 1966. This photo reveals the first view of Earth from the moon, taken by Lunar Orbiter 1 on August 23, 1966. It’s shot from a distance of about 236,000 miles (380,000 kilometers) and shows half of Earth, from Istanbul to Cape Town and areas east, shrouded in night. NASA restored this photo in 2008, using photographic techniques not available in the 1960s. See the restored photo inside.

This date in science: Definitive discovery of Neptune’s rings

Neptune's rings via Voyager 2.

Neptune has a faint, continuous ring system. This Voyager 2 image is shown at increased brightness, to bring out fainter features.

August 22, 1989. When NASA’s Voyager 2 spacecraft skimmed past the planet Neptune on this date, it discovered a faint but continuous ring system encircling the planet. Scientists had suspected there were rings around Neptune some years earlier. After all, Uranus had rings, discovered in 1977. And, watching from Earth in 1984, astronomers were able to see extra blinks before and after Neptune passed in front of a distant star. Still, Voyager 2 made the definitive discovery of Neptune’s rings a few days before it swept closest to the planet.

Best photos of Apollo 11 and first footsteps on moon

Apollo 11:  First human steps on the moon.

Apollo 11: First human steps on the moon.

July 20, 1969. On this date, Apollo 11 astronauts Buzz Aldrin and Neil Armstrong landed their moon module on a broad dark lunar lava flow, called the Sea of Tranquility. Six hours later, Neil Armstrong became the first human being to walk on the moon.

Don’t believe it? Try this video: Why the Apollo moon landings could not have been faked.

This date in science: The day Earth smiled

Via  NASA/JPL/SSI/CICLOPS / Mother Jones

Via NASA/JPL/SSI/CICLOPS / Mother Jones

July 19, 2013. On this date last year, humanity acquired its third-ever image of Earth from the outer solar system, as the planet Saturn eclipsed the sun from the vantage point of an orbiting spacecraft, and as we on Earth cast our thoughts toward space. The Cassini spacecraft imaging team – led by Carolyn Porco – later dubbed this image The Day Earth Smiled. Learn more it, and see the first two images of Earth from deep space, by clicking on the links below.

This date in science: America and Russia meet in space

Astronaut Thomas P. Stafford (in foreground) and cosmonaut Aleksei A. Leonov make their historic handshake in space on July 17, 1975 during the joint U.S.-USSR Apollo Soyuz Test Project (ASTP) docking mission in Earth orbit. This picture was reproduced from a frame of 16mm motion picture film.  Image via NASA.

Astronaut Thomas P. Stafford (in foreground) and cosmonaut Aleksei A. Leonov make their historic handshake in space on July 17, 1975 during the joint U.S.-USSR Apollo Soyuz Test Project (ASTP) docking mission in Earth orbit. This picture was reproduced from a frame of 16mm motion picture film. Image via NASA.

July 17, 1975. On this date, Soviets and Americans accomplished the first joint space docking between two nations in the Apollo-Soyuz Test Project. It marked the cooling of a long era of tense relations between the two world superpowers. Russian Soyuz and American Apollo flights launched within seven-and-a-half hours of each other on July 15, and docked on July 17. Three hours later, the world watched on television as the two mission commanders, Tom Stafford and Alexey Leonov, exchanged the first international handshake in space through the open hatch of the Soyuz.