Space Ghost

http://commons.wikimedia.org/wiki/File:Earth6391.jpg

In September 2002, astronomers noticed something odd: An object about 60 feet long was orbiting Earth. It must have arrived recently, but it didn’t resemble any recently launched spacecraft. It might have been an asteroid … but it appeared, spookily, to bear titanium dioxide paint. Was it an alien ship?

The object disappeared again in June 2003, so officially we’re still baffled. But the best guess is that it’s an old stage of Apollo 12 that somehow wandered away from Earth in 1971, circled the sun about 30 times, and came home to visit. If that’s true then it might come back again in 2032—we can visit it on our rocket scooters.

| Oddities · Science & Math

MacFarlane’s Bear

In 1864, the Inuit gave the skin and skull of an “enormous” yellow-furred bear to naturalist Robert MacFarlane. He packed them up and shipped them to the Smithsonian Institution, where they were placed in storage and forgotten.

Fifty-four years later, zoologist Clinton Hart Merriam unpacked the remains and realized they represented an entirely new species, and MacFarlane’s specimen was apparently the last of its kind. No one has ever seen a living “MacFarlane’s bear,” except for those Inuit — and now their story is lost.

| Oddities · Science & Math

“Interest of Money”

Dr. Price, in the second edition of his “Observations on Reversionary Payments,” says: “It is well known to what prodigious sums money improved for some time at compound interest will increase. A penny so improved from our Saviour’s birth, as to double itself every fourteen years — or, what is nearly the same, put out at five per cent. compound interest at our Saviour’s birth — would by this time have increased to more money than could be contained in 150 millions of globes, each equal to the earth in magnitude, and all solid gold. A shilling, put out at six per cent. compound interest would, in the same time, have increased to a greater sum in gold than the whole solar system could hold, supposing it a sphere equal in diameter to the diameter of Saturn’s orbit. And the earth is to such a sphere as half a square foot, or a quarto page, to the whole surface of the earth.”

— Barkham Burroughs’ Encyclopaedia of Astounding Facts and Useful Information, 1889

| Science & Math

Dudeney Numbers

Only six numbers have this curious property:

1 = 1; 13 = 1
8 = 5 + 1 + 2; 83 = 512
17 = 4 + 9 + 1 + 3; 173 = 4913
18 = 5 + 8 + 3 + 2; 183 = 5832
26 = 1 + 7 + 5 + 7 + 6; 263 = 17576
27 = 1 + 9 + 6 + 8 + 3; 273 = 19683

They’re called Dudeney numbers, after the English author and mathematician who discovered them. (Regular readers know I’m something of a fan.)

| Science & Math

“Lamps Lighted by Currents Passed Through the Human Body”

http://en.wikipedia.org/wiki/Image:Twain_in_Tesla%27s_Lab.jpg

Mark Twain in the laboratory of his friend, inventor Nikola Tesla, where in 1894 Twain briefly became a human light bulb:

In Fig. 13 a most curious and weird phenomenon is illustrated. A few years ago electricians would have considered it quite remarkable, if indeed they do not now. The observer holds a loop of bare wire in his hands. The currents induced in the loop by means of the “resonating” coil over which it is held, traverse the body of the observer, and at the same time, as they pass between his bare hands, they bring two or three lamps held there to bright incandescence. Strange as it may seem, these currents, of a voltage one or two hundred times as high as that employed in electrocution, do not inconvenience the experimenter in the slightest. The extremely high tension of the currents which Mr. Clemens is seen receiving prevents them from doing any harm to him.

— T.C. Martin, “Tesla’s Oscillator and Other Inventions,” Century Magazine, April 1895

| History · Literature · Oddities · Science & Math · Technology

Doomsday Clock

Every issue of the Bulletin of the Atomic Scientists since 1947 has displayed a clock face on its cover, symbolizing the world’s proximity to nuclear war (in the judgment of the bulletin’s board of directors).

At its most dire, the clock stood at two minutes to midnight in 1953, when the United States and the Soviet Union tested thermonuclear devices within nine months of one another. Thirty-eight years later, when the superpowers signed the START treaty in 1991, the clock reached 17 minutes to midnight, its most hopeful position to date.

That doesn’t mean we’re making progress. Today it stands at 7 minutes to midnight — which is just where it started 59 years ago.

| Science & Math · Society

Bullseye

0.999… is the same as 1. Not just very close, but precisely identical:

a = 0.999…
10a = 9.999…
10a – a = 9.999… – 0.999…
9a = 9
a = 1

There’s no trick here. It’s just a mathematical fact that most people find deeply counterintuitive.

| Science & Math