Water for life; for civilization

The Nile and its delta (image from NASA).

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.

Finding science fiction online

Free Speculative Fiction Online is a great, centralized source for tracking down science fiction online. It links to online repositories and the websites of a wide variety of authors: from classics like Asimov to stalwarts like Gaiman. There are hundreds of authors, short stories, and novels (including any number of Hugo and Nebula Award winners), and all of them are free.

Rearranging the map

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.

Exploring Space: Extrasolar planets

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.

Letter from a dying explorer

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.