The Story of the Apollo Guidance Computer, Part 3

Entering commands into the Display and Keyboard (DSKY) of the Apollo Guidance Computer during a simulation. Image courtesy: Draper.

During the development of the Apollo Guidance Computer (AGC) by the MIT Instrumentation Laboratory (see Part 1 and Part 2 for the complete backstory), an inauspicious event occurred sometime during 1965-1966, while the Gemini missions were going on.

The Gemini program helped NASA get ready for the Apollo Moon landings missions by testing out rendezvous and other critical techniques and technologies. Ten crews flew missions in Earth orbit on the two-person Gemini spacecraft.

Continue reading “The Story of the Apollo Guidance Computer, Part 3”

Astronomy Cast Ep. 478: Apollo 8 with Paul Hildebrandt

On Christmas Day, 1968 Frank Borman, James Lovell and William Anders became the first human being to see the far side of the Moon. Their mission, of course, was Apollo 8, the first time human beings had ever left Earth orbit and seen the far side of the Moon. Today we talk all about Apollo 8, with special guest Paul Hildebrandt, director of a new documentary about the mission.

We usually record Astronomy Cast every Friday at 3:00 pm EST / 12:00 pm PST / 20:00 PM UTC. You can watch us live on AstronomyCast.com, or the AstronomyCast YouTube page.

Visit the Astronomy Cast Page to subscribe to the audio podcast!

If you would like to support Astronomy Cast, please visit our page at Patreon here – https://www.patreon.com/astronomycast. We greatly appreciate your support!

If you would like to join the Weekly Space Hangout Crew, visit their site here and sign up. They’re a great team who can help you join our online discussions!

What Does NASA Stand For?

NASA Logo. Credit: NASA

Chances are that if you have lived on this planet for the past half-century, you’ve heard of NASA. As the agency that is in charge of America’s space program, they put a man on the Moon, launched the Hubble Telescope, helped establish the International Space Station, and sent dozens of probes and shuttles into space.

But do you know what the acronym NASA actually stands for? Well, NASA stands for the National Aeronautics and Space Administration. As such, it oversees America’s spaceflight capabilities and conducts valuable research in space. NASA also has various programs on Earth dedicated to flight, hence why the term “Aeronautics” appears in the agency’s name.

Continue reading “What Does NASA Stand For?”

Crazy Space Christmases: Moon Readings, Food Cans And Emergency Repairs

"AstroButch [Butch Wilmore] has set up our Xmas tree in the lab and hung socks for us," tweeted astronaut Samantha Cristoforetti from the International Space Station Dec. 7, 2014. Credit: Samantha Cristoforetti/Twitter

If you think the upside-down Christmas tree above is bizarre — that’s one of the latest activities of Expedition 42 astronauts in space right now — think back to the history of other holidays in orbit.

We’ve seen a vital telescope undergo repairs, an emergency replacement of part of a space station’s cooling system, and even a tree made of food cans. Learn more about these fun holiday times below.

Reading from above the moon (Apollo 8, 1969)

In this famous reading from the Bible, astronauts Frank Borman, Jim Lovell and Bill Anders shared their experience looking at the Moon on Dec. 24, 1968. The Apollo 8 crew was the first to venture to lunar orbit, just seven months before the Apollo 11 crew made it all the way to the surface.

Food can “Christmas tree” (Skylab 4, 1973)

A "Christmas tree" created out of food cans by the Skylab 4 crew in 1973. Credit: NASA
A “Christmas tree” created out of food cans by the Skylab 4 crew in 1973. Credit: NASA

Living on the Skylab station taught astronauts the value of improvisation, such as when the first crew (under NASA’s instructions) repaired a sunshield to stop electronics and people from roasting inside. Skylab 4 took the creativity to Christmas when they created a tree out of food cans.

Hubble Space Telescope repair (STS-103, 1999)

The Hubble Space Telescope during a 1999 repair mission with STS-103 crew members Mike Foale (left, for NASA) and Claude Nicollier (European Space Agency). Credit: NASA
The Hubble Space Telescope during a 1999 repair mission with STS-103 crew members Mike Foale (left, for NASA) and Claude Nicollier (European Space Agency). Credit: NASA

When the Hubble Space Telescope was in hibernation due to a failed gyroscope, the STS-103 crew made repairs in December 1999 that culminated with the final spacewalk on Christmas Day. The telescope remains in great shape to this day, following another repair mission in 2009.

First Christmas on the International Space Station (Expedition 1, 2000)

The Expedition 1 crew with fresh oranges on the International Space Station in December 2000. From left, Yuri Gidzenko (Roscosmos), Bill Shepherd (NASA) and Sergei Krikalev (Roscosmos). Credit: NASA
The Expedition 1 crew with fresh oranges on the International Space Station in December 2000. From left, Yuri Gidzenko (Roscosmos), Bill Shepherd (NASA) and Sergei Krikalev (Roscosmos). Credit: NASA

The Expedition 1 crew was the first on the International Space Station to spend Christmas in orbit. “On this night, we would like to share with all-our good fortune on this space adventure; our wonder and excitement as we gaze on the Earth’s splendor; and our strong sense — that the human spirit to do, to explore, to discover — has no limit,” the crew said in a statement on Christmas Eve, in part.

Ammonia tank replacement (Expedition 38, 2013)

Just last year, an ammonia tank failure crippled a bunch of systems on the International Space Station and forced spacewalkers outside to fix the problem, in the middle of a leaky suit investigation. The astronauts made the final repairs ahead of schedule, on Christmas Eve.

Watch All The Apollo Saturn V Rockets Blast Off At The Same Time

Screenshot of a video showing all the Saturn V launches happening at the same time. Credit: SpaceOperaFR/YouTube (screenshot)

Editor’s note: We posted this yesterday only to find that the original video we used had been pulled. Now, we’ve reposted the article with a new and improved version of the video, thanks to Spacecraft Films.

To the moon! The goal people most remember from the Apollo program was setting foot on the surface of our closest neighbor. To get there required a heck of a lot of firepower, bundled in the Saturn V rocket. The video above gives you the unique treat of watching each rocket launch at the same time.

Some notes on the rockets you see:

  • Apollos 4 and 6 were uncrewed test flights.
  • Apollo 9 was an Earth-orbit flight to (principally) test the lunar module.
  • Apollo 8 and 10 were both flights around the moon (with no lunar landing).
  • Apollo 13 was originally scheduled to land on the moon but famously experienced a dangerous explosion that forced the astronauts to come back to Earth early — but safely.
  • Apollos 11, 12, 14, 15, 16 and 17 safely made it to the moon’s surface and back.
  • Skylab’s launch was also uncrewed; the Saturn V was used in this case to send a space station into Earth’s orbit that was used by three crews in the 1970s.
  • You don’t see Apollo 7 pictured here because it did not use the Saturn V rocket; it instead used the Saturn IB. It was an Earth-orbiting flight and the first successful manned one of the Apollo program. (Apollo 1 was the first scheduled crew, but the three men died in a launch pad fire.)

And if this isn’t enough firepower for you, how about all 135 space shuttle launches at the same time?

Read more about the Saturn V at NASA and the Smithsonian National Air and Space Museum.

(h/t Sploid)

All Saturn V Launches At Once from Spacecraft Films on Vimeo.

What’s On The Far Side Of The Moon?

What's On The Far Side Of The Moon?

You probably know we only see one side of the Moon from the Earth. But for the majority of human history, we had no idea what the far side looked like.

Billions of years ago, our Moon was formed when a Mars-sized object smashed into the Earth, spinning out a ring of debris. This debris collected into the Moon we know today. It started out rotating from our perspective, but the Earth’s gravity slowed it down until its rotation became locked with the Earth’s, keeping one half forever hidden from our view.

It wasn’t until the space age that humans finally got a chance to see what’s on the other side. The first spacecraft to image the far side of the Moon was the Soviet Luna 3 probe in 1959, which returned 18 usable images to scientists. And then in 1965, the Soviet Zond 3 transmitted another 25 pictures of higher quality that gave much more detail of the surface. The first humans to actually see the far side with their own eyes, were the crew of Apollo 8, who did a flyover in 1968.

We now have high resolution cameras imaging every square meter, even the far side. And here’s the amazing surprise….

You would think that the far side of the Moon would look like the near side, but check out the two hemispheres…They’re totally different.

The near side of the has huge regions of ancient lava flows, called maria. While the far side is almost entirely covered in crater impacts. Planetary geologists aren’t sure, but it’s possible that the Earth used to have two Moons.

Billions of years ago, the second, smaller moon crashed into the far side of the Moon, covering up the darker maria regions.

And just to clarify things with Pink Floyd’s reference to the “Dark Side of the Moon”… Except for the occasional lunar eclipse, half of the Moon is always in darkness and half is always illuminated. But that illuminated half changes as the Moon orbits around us.

High resolution photo map of the moon's far side imaged by NASA's Lunar Reconnaissance Orbiter. Mare Moscoviense lies at upper left and Tsiolkovsky at lower left. Click for a hi res image. Credit: NASA
High resolution photo map of the moon’s far side imaged by NASA’s Lunar Reconnaissance Orbiter. Credit: NASA

Just like half of the Earth is always in darkness, and half of every other large object in the Solar System. There’s no permanent “dark side” of the Moon. The side facing towards the Sun is lit up, and the side facing away is in shadows.

There are, however, some spots on the Moon which are in eternal darkness. There are craters at the north and south poles deep enough that the light from the Sun never illuminates their floors. In these places, It’s possible that there are reserves of ice that future space colonies could use for their supplies of water, air, and even rocket fuel.

Pink Floyd was right if you’re talking radio waves instead of visible light. The far side of the Moon is naturally shielded from the Earth’s radio transmissions, so it makes an ideal spot to locate a sensitive radio observatory.

I’ll see you in the permanently shadowed craters of the Moon.

See the Apollo 8 “Earthrise” in a Whole New Way

Earthrise - Apollo 8
Earthrise - as seen from Apollo 8. Credit: NASA.

One of the most famous images from the history of spaceflight is the picture taken by the crew of Apollo 8 of the “Earthrise” — the first color picture of taken of Earth as it became visible as the spacecraft came from behind the farside of the Moon. The photo was taken 45 years ago on December 24, 1968. It’s been called one of the most influential environmental photographs ever taken, and is one of the most-published pictures ever. As the photographer of this photo, astronaut Bill Anders has said, “We came all this way to discover the Moon. And what we really did discover is Earth.”

The NASA Goddard Scientific Visualization Studio has now released a new video that is a re-creation of that first Earthrise. The video is based on detailed analysis of Apollo 8 photography, including vertical stereo photos that were being taken at the same time as the Earthrise photos, combined with recent topographic models from the Lunar Reconnaissance Orbiter.

“In the video,” space historian Andrew Chaikin — who narrates the new video — told Universe Today, “we see the Moon’s surface, generated from LRO data, exactly as it appeared to the astronauts through the different windows of the spacecraft. We also hear the astronauts’ voices as captured by the spacecraft’s onboard voice recorder, synchronized with the visual. The video reveals new details about this historic event and the resulting color photograph, which became an icon of the 20th century.”

Enjoy this wonderful new video, which explains how this historic image was taken. The visualization shows how Apollo 8 Commander Frank Borman and crew members Anders and James Lovell worked together to photograph the stunning scene as their spacecraft orbited the Moon in 1968. The video allows anyone to virtually ride with the astronauts and experience the awe they felt at the vista in front of them.

The “Earthrise” photo is the cover photo of TIME’s Great Images of the 20th Century, and is the central photo on the cover of LIFE’s 100 Photographs That Changed the World.

“Earthrise had a profound impact on our attitudes toward our home planet, quickly becoming an icon of the environmental movement,” said Ernie Wright, who lead the video project with the SVS.

You can read more details of how the video was put together in this NASA press release.

A computer-generated visualization of the Apollo 8 spacecraft in orbit around the moon, with Earth rising over the horizon. Image Credit:  Ernie Wright/NASA Goddard Scientific Visualization Studio
A computer-generated visualization of the Apollo 8 spacecraft in orbit around the moon, with Earth rising over the horizon.
Image Credit:
Ernie Wright/NASA Goddard Scientific Visualization Studio

Earthrise, Revisited

The first color photo of Earth taken from orbit around the Moon. (NASA)


On December 24, 1968, Apollo 8 astronauts Frank Borman, William Anders and Jim Lovell were the first humans to witness an Earthrise as our home planet came up over the lunar horizon. The photos they captured were the first of their kind, instantly inspiring the imaginations of millions and highlighting the beauty and fragility of our world.

Now, NASA has used modern satellite data to recreate the scenes that the Apollo 8 astronauts saw 44 years ago and combined them with their historic photographs to present a new “Earthrise”… version 2.0.

Created in recognition of Earth Day 2012, the Earthrise animation was made from data acquired by NASA’s Lunar Reconnaissance Orbiter’s laser altimeter, as well as the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra Earth-observing satellite.

“This visualization recreates for everyone the wondrous experience of seeing Earth from that privileged viewpoint,” says LRO Project Scientist Rich Vondrak of NASA’s Goddard Space Flight Center.

Animator Ernie Wright recreated the scene using Apollo mission reports and photos taken by the crew. The audio is a recording of original communication from the astronauts.

[/caption]

“I think the one overwhelming emotion that we had was when we saw the earth rising in the distance over the lunar landscape… it makes us realize that we all do exist on one small globe. For from 230,000 miles away it really is a small planet.”

— Frank Borman, Apollo 8 Commander

Read the release on the NASA LRO site here.

Video: NASA/GSFC