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December 7, 1972 – The Earth is Blue

The first photographs that we have of the planet that we call home — Okay I call planet Earth home. If you are reading this on another planet can you say hi? I would love to chat with you?– was a black and white photo taken from the satellite TIROS-1 in 1960.

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Earth from TIROS-1 April 1, 1960
Image Source: Nasa.gov

It was not until astronauts Eugene A. Cernan, Harrison H. Schmitt, and Ronald E. Evans took the Blue Marble photograph on their way to the moon were we able to get a color photo.

Apollo 17 launched at 5:33 am GMT on December 7, 1972 from Kennedy Space Center. It was to be the last mission to put men on the moon. It was also the first mission the a geologist was going to walk on the moon. And was the first night launch of the Apollo missions.

They were aiming the rocket at a full moon targeting for a landing site in the Valley of Taurus Littrow. Geologist felt that this was most likely an undisturbed part of the moon.

Since the mission was at night, it gave the astronauts a great chance to see the entire earth. In order to do that the rocket traveling at 20,000 miles an hour needed to pass between the Earth and the Sun. This was the first time that any of the Apollo crews got to see the entire planet, or the entire moon. Other flights only glimpsed partials.

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The Blue Marble
Image Source: Nasa.gov

Shortly after leaving orbit on the way to the moon –at about 28,000 miles away– they took what has to be the most famous picture of our planet. Officially named AS17-148-22727 otherwise know as the Blue Marble.

They were busy as hell the first six hours. Lunar missions only made two orbits around the earth, three hours of frantic preparation before cranking it up to escape velocity. They were coming around to the daylight side for the third time when the last booster fired for six minutes to propel them away from the human planet. There were a thousand critical things they had to do next: separate from that final booster stage, accomplish a delicate docking maneuver with the service module, reorient and stabilize their new combined spacecraft, check all the various systems and compute their trajectory, and climb out of the awkward hardsuits they’d been wearing since blast-off.

They weren’t supposed to be taking pictures. Photo sessions were scheduled events in a rigorous flight plan that detailed every step essential to success. The film itself was strictly rationed like everything else on those perilous flights; there were 23 magazines onboard for the 70mm Hasselblad cameras, twelve color and eleven black-and-white, all intended for serious documentation purposes. They weren’t supposed to be looking out the window, either.

But they couldn’t help it, none of them. If you talk to any of the lunar travelers today — eighteen of them are still alive — they will talk most about and remember best the stolen moments of watching their home world shrink behind them. It was a blue-green beacon in a vast black cosmos, beguiling them on a cellular level, getting smaller by the minute. Forty years later the journey that lives most intensely for them was more about leaving the Earth than going to the moon.

At five hours and a few minutes into the flight of Apollo 17 one of the crewmen looked out the window. What he saw inspired him to grab the only Hasselblad that wasn’t stowed and snap a picture — actually four pictures, no more than a minute apart, changing the exposure after the first one. The second snap yielded the sharper image that’s become famous, so a minute’s attention was involved. But whoever did it said nothing on the radio or to their crewmates about it. It’s possible they did it instinctively, hardly thinking about it, because none of them thought to mention it for weeks.

TheAtlantic.com

The original photo was upside down. Meaning that Antarctica was on the top of the photo. It was altered by NASA before publication. After seeing the image a few weeks later all three of the men on board claimed to have taken the photograph.

In 2002 Nasa produced The Blue Marble. It is the most detailed image of the entire globe using observation satellites. They used digitizers to piece the photo together.

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The Blue Marble
Image Source: Nasa.gov

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