This nighttime photograph of the Nile River and its delta from the International Space Station beautifully illustrate the importance of water for life and civilization. The city of Cairo is at the neck of the delta; the brighter spot where the distributaries diverge.
Spaceflight Now has other really cool photos. Bad Astronomy has an interesting post on the logistics of this particular photo, while Heather Pringle has a very interesting post on how the desert may have aided the ancient Egyptian’s civilization.
What if you exchanged countries based on population for land area? So China, which is the most populous country would take the place of Russia, which has the largest area. It would create the intriguing map below (from the wonderful blog, Strange Maps).
World Map if the largest countries had the biggest populations. Map by Frank Jacobs.
Notice the planet in the lower right corner? (Image from the Hubble Space Telescope via Wikipedia).
One of the neatest developments in recent space exploration has been the accelerating discovery of planets orbiting other stars. Other stars are just so far away that it’s insanely difficult to see anything orbiting them. Also, the stars can be much brighter, a billion times even, than the planets. So, in the beginning, they could just identify the largest of planets, Jupiter sized and bigger, because of they way they make their stars wobble, but this and other techniques have gotten better and better and now we’re looking at smaller and smaller planets, getting down to Earth sized objects.
Methods for detecting planets orbing other stars. Image by M. Perryman.
One of my students, in investigating modern space exploration, found The Extrasolar Planets Encyclopaedia, which is pretty sweet because it keeps a running tally of planets found outside our solar system. When he found it last week the number was 502, now it’s 504. The site also has a long list of the ground and space based projects looking for extrasolar planets, which demonstrates how active the field is today.
While discussing polar exploration, I mentioned the story of Amundsen and Scott’s race for the south pole. The fascinating blog, Letters of Note, has Scott’s last letter, written bit by bit, on the ice, to his wife back home. It starts, “To: my widow.”
Photograph of Scott's (far left) expedition at the South Pole, on 17 January 1912, the day after they discovered Amundsen had reached the pole first. (Photo via Wikimedia Commons)
P.S. Letters of Note is a great resource for examples of great letter writing.
One of my students is working on a personal project on ice dogs and how they aid polar exploration today and in the past. Amazingly, dogs are still used in expeditions that spend the winter on the ice, as shown in the video from the Tara expedition of 2006 (hat tip to Ryan):
NPR’s Planet Money has a nice story on why gold is used for money. They take the entire periodic table of elements and eliminate the ones that don’t work because they’re too reactive, a gas, too common, or too toxic. You’re left with five precious metals, rhodium, palladium, silver, platinum and gold, but only one of them has a low enough melting temperature so that it can be worked easily and is not ridiculously rare.
Also, Tony Clayton has a wonderful webpage on Metals Used in Coins and Medals. It has some fascinating details about the history of these metals and their alloys in coinage. For example, “In Old English the Latin word aes was rendered as brass, thus the use of the word brass to mean money still found today, especially in Northern England. “
Amargosa Toad (Bufo nelsoni). Photo from US Fish and Wildlife (M. Burroughs).
NPR had facinating story recently about unlikely groups working together. It’s about a town in Nevada that banded together to save a toad from going extinct. The groups working together include environmentalists and the Saving Toads thru Off-Road Racing, Mining and Ranching in Oasis Valley (aka STORM-OV).
Controversial map purporting to be based on an earlier 1418 map of Chinese exploration of the world. Image from Wikimedia Commons.
Most of the exploration we studied this cycle were European expeditions. One group wanted to do something a little different, so I suggested they look in to Chinese explorations of other parts of the world. There was much Chinese commerce across the Indian Ocean, and in a non-Christian twist on the “God” theme for exploration, the Chinese brought Buddhism back from India in the third century AD (we’re studying exploration under the themes of God, Gold and Glory).
Another interesting aspect of research into Chinese exploration is the rather controversial work by Gavin Menzies that suggests that great Chinese fleets explored the Americas and circumnavigated the globe in the 1420’s, a long time before Columbus and Magellan.
There is a lot of evidence that there was no such Chinese expedition, but it’s a fascinating hypothesis and, in a way, very similar to the All About Explorers project: although Menzies’ work is not an intentionally educational hoax. Indeed, it is much more subtle and much more detailed. My favorite line of critique asserts that Menzies’ books, “.. may well prove to be the Piltdown Man of literature.” I don’t know if I’ll have the time to try to unpack that one for my students.
