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Items tagged with: otd

The first message between two computers on ARPANET was sent #OTD in 1969. The “LO” of “LOGIN” was successfully transmitted and then one of the systems crashed.

Charles Kline’s IMP Log: “Talked to SRI host to host.”

Image: UCLA Kleinrock Center for Internet Studies

Charles Kline’s IMP Log reads: “22:30 Talked to SRI host to host.”

Happy 115th birthday, spacetime!

Hermann Minkowski addressed the 80th Assembly of German Natural Scientists and Physicians #OTD in 1908, offering a radical four-dimensional reformulation of Einstein's theory of special relativity.

His opening lines:

The image displays the following quote:
“The views of space and time which I wish to lay before you have sprung from the soil of experimental physics, and therein lies their strength. They are radical. Henceforth space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality.”
								— Hermann Minkowski, 1908

The Voyager 1 space probe was launched from Cape Canaveral #OTD in 1977, a few weeks after Voyager 2.

Now it's the most distant human-made object – about 14.96 billion miles from Earth, racing away from us at 38,000 miles per hour with respect to the Sun.


Color photo of the Voyager 1 launch. The probe sits atop a rocket mounted on a larger rocket with twin solid fuel boosters – a Titan IIIE launch vehicle. The photo is taken just after ignition. The bottom of the rocket has lifted up about half the height of the gantry, and is engulfed in bright white flame and smoke.
Color plot of the Voyager 1 and Voyager 2 trajectories. While Voyager two visited all four outer planets, Voyager 1 took a quicker route to Jupiter and Saturn that sent it careening out of the solar system.
A color rendering of the Voyager 1 probe against a star field. Two prominent antenna gantries emerge from the main body of the probe, positioned underneath a large radio dish.

Geneticist Liane Russell was born #OTD in 1923.

She pioneered the study of mutagenesis and teratogenesis due to radiation, and identified the role of the Y chromosome in sex determination. Her work led to diagnostic x-ray safety standards for women of childbearing age.

Science, the joy of wild places, and civic engagement as a response to fascism – this is one of my favorite threads.

A young Liane Russell working with a mouse. She is in a lab, wearing a white shirt. Someone outside the frame of the picture is also touching the mouse. Image: Oak Ridge National Laboratory

Antoni van Leeuwenhoek died #OTD in 1723.

A largely self-taught man in science, he is commonly known as "the Father of Microbiology", and one of the first microscopists and microbiologists. Van Leeuwenhoek is best known for his pioneering work in microscopy and for his contributions toward the establishment of microbiology as a scientific discipline. via @wikipedia

Books by Antoni van Leeuwenhoek at PG:

#books #science #microbiology

Portrait of Anthony van Leeuwenhoek (1632-1723), physicist in Delft. Knee piece, seated at a writing table on which lies a certificate of his appointment as a member of the Royal Society of Physicians in London by Charles II. Also, a globe and an inkstand; he holds a compass in his hand.
Illustration of critique of Observationes microscopicae Antonii Levvenhoeck... published in Acta Eruditorum, 1682.

Hey, that's us!

#OTD in 1959, Explorer 6 took the first photo of Earth ever taken by a satellite! It transmitted this image of a sunlit portion of the north central Pacific Ocean.

See more of the first photos of Earth from space:

3 days after being released from quarantine, Apollo 11 astronauts Neil Armstrong, Buzz Aldrin, and Michael Collins were showered with ticker tape and cheered on by an exuberant crowd in New York City #OTD in 1969.

More about the celebrations:

A Soaring Success!

#OTD in 1977, NASA's first space shuttle orbiter Enterprise completed its first free flight, with Fred Haise and Gordon Fullerton piloting it down to the runway at @NASAArmstrong.

Watch video from the flight:

#OTD in 2011, NASA's Dawn spacecraft captured these images of the asteroid Vesta on its mission to characterize the processes of our solar system's early evolution.

More about Dawn's mission:

#OTD in 2005, STS-114 completed the Space Shuttle Program's 14-day "Return to Space" mission, the first after the tragic loss of Columbia 2.5 years earlier.


#OTD 5 years ago, NASA's Transiting Exoplanet Survey Satellite (TESS) captured its first light image, showing a wide swath of the southern sky using all four of its wide field cameras (image from one camera shown here).

Read about what TESS is up to now:

#OTD in 1971, the Apollo 15 Command Module "Endeavour," with astronauts Dave Scott, Al Worden and Jim Irwin aboard, splashed down in the Pacific Ocean to end their mission. Although 1 of the 3 main parachutes collapsed, the crew was unharmed.


Owen Garriott (shown here) and his Skylab 3 crewmates performed a nearly 6.5 hour spacewalk #OTD in 1973 to install a 2-pole sunshade, change the film on the Apollo Telescope Mount, and install and repair equipment for experiments. #Skylab50

Learn more:

Did Mars ever have the right conditions to support life?

#OTD in 2012, the @MarsCuriosity rover landed on the Red Planet. Sampling Martian rocks over 19 miles and 11 years, Curiosity continues to shine a light on Mars's history.

Where is Curiosity now?

More than what meets the eye...

@NASAJuno launched on its 5-year journey to Jupiter #OTD in 2011. It has revealed what's under the planet's outer layer of swirling clouds, and provided unprecedented views of Jupiter and its moons.

What is Juno up to now?

Happy 11th Landiversary, @MarsCuriosity! #OTD the rover survived its wild ride down to a safe landing on Mars. This mountaineering adventurer continues to explore and is facing its toughest climb yet. Catch up on Curiosity’s journey:

Phoenix is so hot! 🔥

The Phoenix Mars Lander that is. #OTD in 2007, Phoenix was launched to the Red Planet on a mission to investigate the biological potential in Mars's icy far North. @NASAMars @NASAJPL

Dig in to its chilly findings:

The first spacecraft to orbit Mercury 🛰️

#OTD in 2004, the MESSENGER spacecraft launched to Mercury. It returned nearly 300,000 images over its 4 years in Mercury's orbit, revealing past volcanic activity and the presence of water ice.

Learn more:

What could be better than experiments in space? Experiments on the Moon!

#OTD in 1971, Apollo 15 astronaut David Scott performed his feather and hammer experiment on the Moon, demonstrating that without air resistance all objects fall at the same rate.

During their first few days on Skylab, @NASA_Astronauts Al Bean, Owen Garriott, and Jack Lousma moved slowly to minimize their vertigo as they adjusted to weightlessness.

In this image taken #OTD in 1973, they have a meal together. #Skylab50


Pilot John Manke first flew the X-24B, the "flying flatiron," on a glide flight #OTD in 1973. These glide missions represented the final milestone in NASA's piloted lifting body program that helped write flight plans for space shuttle landings.


Before 1964, we had no close-up photos of the Moon, and it wasn't known if astronauts could feasibly land on its surface. That changed when Ranger 7 sent back 4,316 images of the lunar surface before impacting the Moon #OTD in 1964.

More about Ranger 7:

#art #history: kate bush (born #otd in 1958) is someone i draw once a year - & i guess i've done trading cards this time. 😀
i love kate because she:
a) clarified her statement about theresa may
b) has been vegetarian forever &, in 1980, schooled delia smith about it
c) has donated to the hunt saboteurs
d) is in a complete league of her own
#kateBush #illustration #portrait #vegetarian #music #huntsabs
illustration of musician, kate bush, that i drew with digital pencil & ink tools. kate wears a mischievous face as she smiles directly at the audience. colours are pale blue, orange-pink & black. there's a segmented triangle in the upper left corner & three thin, black lines make a frame around the image. illustration of musician, kate bush, that i drew with digital pencil & ink tools. kate wears a mischievous face as she smiles directly at the audience. colours are white, orange-pink & black. there's a segmented triangle in the upper left corner & three thin, black lines make a frame around the image.
illustration of musician, kate bush, that i drew with digital pencil & ink tools. kate wears a mischievous face as she smiles directly at the audience. colours are pale green, white & black. there's a segmented triangle in the upper left corner & three thin, black lines make a frame around the image. illustration of musician, kate bush, that i drew with digital pencil & ink tools. kate wears a mischievous face as she smiles directly at the audience. colours are cream, black cherry & black. there's a segmented triangle in the upper left corner & three thin, black lines make a frame around the image.

Astronauts Dave Scott and Jim Irwin landed the Apollo 15 lunar module "Falcon" at the Hadley-Appenine site on the Moon #OTD in 1971. After landing, Scott performed the only stand-up EVA from the top hatch of the LM ever done.

Learn more about Apollo 15:

Incredible journeys are better with your bestie

#OTD in 2020, the @NASAPersevere rover and Ingenuity helicopter began their adventure to Mars, lifting off from Cape Canaveral at 7:50 AM ET.

More on Perseverance:
And Ingenuity:

Taken #OTD in 2006, this Hubble shot shows a rare eclipse on Uranus!

The shadow of one of the planets' icy moons, Ariel, is seen on the surface. Ariel is the tiny white dot near the center of the planet.

Find out more about this astronomical alignment:

Get in Irwin, we're going Moon driving!

Apollo 15, the 4th mission to put humans on the Moon, launched #OTD in 1971. Folded up in the lunar module (LM) was the first Lunar Roving Vehicle, allowing Dave Scott and Jim Irwin to venture farther from the LM.

NASA Administrator Dr. Thomas Paine (left) and U.S. President Richard M. Nixon wait aboard the U.S.S. Hornet recovery ship for the splashdown of the Apollo 11 command module #OTD in 1969.

Read more about Apollo 11's return to Earth:

Happy 24th birthday @chandraxray! Seen here just before being deployed from Space Shuttle Columbia (STS-93) #OTD in 1999, this powerful space observatory was initially expected to function for 5 years.

Read how Chandra has vastly advanced X-ray astronomy:

Happy #InternationalMoonDay!

#OTD 54 years ago, the Apollo 11 crew became the first humans to set foot on the lunar surface.

With #Artemis, we will build on Apollo to establish long-term human infrastructure on the Moon.
#NASAArtemis #Artemis

"That's one small step for [a] man, one giant leap for mankind."

Neil Armstrong's famous words upon stepping onto the Moon's surface were witnessed by 650 million people from around the globe #OTD in 1969. Watch ▶️

Do you have recollections of this day?

#OTD in 1966, John Young and Michael Collins launched for the 3-day Gemini X mission. The astronauts rendezvoused with 2 Agena target vehicles, set a record altitude for humans in space, and performed a spacewalk from one spacecraft to another.

Read more

Major General Robert White earned his astronaut wings in the X-15 when he reached 95.9 km (59.6 mi) in altitude #OTD in 1962, setting a world record.

Oh, and he was also the first pilot to fly to Mach 4, 5 & 6 #avgeeks #aviation @NASAaero

📷 @usairforce

#OTD in 2011, NASA's Dawn spacecraft entered Vesta's orbit, studying the asteroid's geology and composition. Dawn revealed that Vesta is actually a protoplanet surviving from the earliest days of the solar system!

Learn more about the Dawn mission:

Fueling up for an epic day in spaceflight history 🥩 🍳

Apollo 11 astronauts Neil Armstrong, Michael Collins and Buzz Aldrin were joined by Bill Anders (left) and Deke Slayton (right) for the traditional pre-flight breakfast of steak and eggs hours before liftoff #OTD in 1969.

This is aerospace engineer John C. Houbolt, the leading proponent of the lunar orbit rendezvous (LOR) plan (chosen #OTD in 1962) which made possible John F. Kennedy's goal of sending astronauts to the Moon and bringing them back home safely before the end of the 1960s. 🧵

#OTD 12 years ago, the Space Shuttle Atlantis approaches the space station for docking for the last time on July 10, 2011. The final flight of the Space Shuttle program has us remembering many triumphs, fallen heroes, and signature moments. More:
#otd #iss

The Day Communication Went Global 🌍

Telstar 1, the world's first active communication satellite, was launched by NASA #OTD in 1962. Almost two weeks later, it relayed the first live transatlantic TV broadcast.

Watch 1962 news footage:

📷 @BellLabs

"Music is a hidden arithmetic exercise of the soul, which does not know that it is counting."

Gottfried Wilhelm Leibniz was born #OTD in 1646. He was a mathematician, philosopher, scientist and diplomat. He is a prominent figure in both the history of philosophy and the history of mathematics. He wrote works on philosophy, theology, ethics, politics, law, history and philology. via @Wikipedia

Books by Gottfried Wilhelm Leibniz at PG:

#books #philosophy #mathematics

Christoph Bernhard Francke - Bildnis des Philosophen Leibniz (ca. 1695), Herzog Anton Ulrich-Museum. via @wikipedia
Leibniz's correspondence, papers and notes from 1669 to 1704, National Library of Poland. via @wikipedia

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