Welcome to Planet Earth
, the third planet from a star
named the Su.
The Earth is shaped like a sphere
and composed mostly of rock
. Over 70 percent of the Earth's surface is water
The planet has a relatively thin atmosphere
composed mostly of nitrogen and oxygen. Earth has a single large Moon
that is about 1/4 of its diameter and, from the planet's surface, is seen to have almost exactly the same angular size as the Sun
With its abundance of liquid water
supports a large variety of life forms, including potentially intelligent species such as dolphins
. Please enjoy your stay
on Planet Earth
View of the Earth as seen by the Apollo 17 crew traveling toward the moon. This translunar coast photograph extends from the Meditierranean Sea area to the Antarctica south polar ice cap. This is the first time the Apollo trajectory made it possible to photograph the south polar ice cap.
Note the heavy cloud cover in the southern hemisphere. Almost the entire coastline of Africa is clearly visible. The Arabian Peninsula can be seen at the northeastern edge of Africa. The large island off the coast of Africa is the Malagasy Republic. The Asian mainland is on the horizon toward the northeast.
Apollo 17 was NASA's last and most successful manned Moon mission. Within just a few hours of launch the crew were 24,000 km away and could see an entire hemisphere of Earth. The photo they took was labelled AS17-148-22726 and was added to the hundreds of thousands of others in the NASA archives. And there it would have remained, were it not for environmental organisations and famine-relief organisations of the early 1980's. Its prominent depiction of Africa and Antarctica made it perfectly suited as symbols for both causes. Posters started appearing pairing the photo with captions such as "It's the only one we've got".
This initial boost was all that was needed to start a monopoly. From then on, whenever someone was seeking to use a photograph of Earth, naturally it was an example of AS17-148-22726 that one would find first. Television, newspapers, websites, mouse pads and marketing material are all oozing with copies of the photograph. Yet astonishingly few people notice that they are being presented with the same photo over and over.
Photo Credit: NASA JSC