Numberplay: How Many Light Bulbs Does It Take ...
A set of puzzles involving light bulbs. feeds.nytimes.com |
Spacewatch: Jupiter's extraordinary moons
This January brought the 400th anniversary of Galileo's discovery of the four main moons of Jupiter, a finding that helped to demolish the idea that all celestial objects circled the Earth. His crude telescope would be no match for those widely available now, and even decent binoculars are enough to glimpse the Jovian moons. Check for yourself as Jupiter climbs brightly through the E and SE this evening (15 September).Since the first flyby of the planet by Pioneer 10 in 1973, those moons, named Io, Europa, Ganymede and Callisto in order from Jupiter, have become recognised as interesting worlds in their own right. Io is the most hostile: bathed in an intense belt of radiation and tidally squeezed between Jupiter and the other moons, it is the most geologically active body we know. More than 400 volcanoes spew lava and towering sulphurous plumes that paint and repaint the surface in hues that range from yellow and green to white and red.Ganymede surpasses Mercury in diameter, while Callisto comes close: both may harbour oceans of water under their rocky and icy surfaces. It is the likely subsurface ocean of Europa that is usually seen as a possible location for extraterrestrial life, though it may be decades before anyone gets to drill through its icy crust to investigate directly. Meanwhile, Nasa and ESA are considering a joint mission for launch in 2020 to discover whether habitable conditions might exist on Jupiter's moons.Alan Pickupguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
Soaring Aussie demand guzzles biofuels supply
A report suggests Australian demand for biofuels has outstripped the rate of global production growth in the past year. abc.net.au |
The number game
Numerologists get a far better press than they deserve, but Matt Parker finds he has an unexpected empathy with themI like patterns. I only ever buy palindromic values of petrol because numbers such as £34.43 not only make me smile but are easy to spot on a bank statement. Humans have an innate love of patterns and our ability to exploit them has led to modern civilisation. People enjoy sudoku for the thrill of completing a puzzle and the same numerical patterns underpin modern information technology.So I was happy to talk to the Daily Mail about yesterday's date – 10/10/10. There is nothing inherently amazing about it; it's just a quirk of the fact that we divide the solar year into 12 months of which we're in the 10th (when we could have any number of months) and that the calendar we use was zeroed 2,010 years ago (which isn't the case in many other cultures). But there is still something satisfying about the time 10:10am and 10 seconds on 10/10/10. Just like I remember stopping at 1:23pm and 45 seconds on 6/7/89. And mark your calendar for later this month when the date will be 20/10/2010.Then I read the Daily Mail article last Friday and saw it also had comments from my nemeses: numerologists.If you want to irritate astronomers, call them astrologers. To see mathematicians get downright emotional, talk to them in earnest about numerology. According to numerologists, the satisfying 10/10/10 date is "not just a once in a 100 years quirk of the calendar", but rather, the numbers have deeper meaning. Just like how the numbers from the date you were born, the position of the letters of your name in the alphabet and even your house number, affect who you are and even predict the future. Which feels like a lot of meaning to attach to arbitrary numbers.As for what the number 10 actually means, the Mail asked Sonia Ducie, author of Numerology: Your Personal Guide For Life, who said: "Ten is the number for wisdom, because it contains the essence of all the numbers of one to nine within it."Firstly, one to nine are just the digits that we happen to use. They are the symbols we use to represent numbers. Any number, such as 36 for example, is the same number when it is written "normally" as 36 or in binary as 100100 or in base-five as 121. We happen to use base-10 numbers because we have 10 fingers to count on (also called digits); if humans had evolved with five fingers we'd probably write 36 as 121.Not only that, but I'm not sure exactly how 10 contains the essence of one to nine within it. It seems to be just because it is bigger than one to nine, which means that every number contains the essence of every number smaller than it. This is the kind of vacuous but sciencey-sounding effluent that gushes from purveyors of pseudoscience.As you can see, I'm now getting a bit emotional. Honestly though, I do have some empathy for numerologists because I'm driven by the same thirst for patterns and causality. As humans, we all are. Our craving for patterns and logic means that we tend to seek patterns where there are none; clutching at random straws. We selectively manipulate things to produce patterns. The date is a perfect example: we use "2010" sometimes and "10" at other times, depending on which looks nicer, we switch between 12- and 24-hour time to get the most aesthetic numbers. We remember the times when seven is lucky and ignore all the occasions when it isn't. It is science and mathematics that allow us to overcome this innate tendency to generalise and separate the spurious from the insightful; coincidence from causal.Our being wired to spot patterns and make connections allowed civilisation to develop, and our ability to rationally manipulate and exploit patterns has provided civilisation with all its life-changing technology. Everything from modern medicine to mobile phones and computers exists because we didn't just decide that 10 is the number for wisdom and call it a day. Without our species' passion for meaning and order being balanced by our capacity for logic we would have nothing. Not even a sudoku to pass the time.Matt Parker is based in the mathematics department at Queen Mary, University of London. His lucky number is 496.Matt blogs at Stand-up MathematicianMathematicsMatt Parkerguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
Astronomers say they've found oldest galaxy so far
By SETH BORENSTEIN 2010-10-20T21:17:28ZWASHINGTON (AP) -- Astronomers believe they've found the oldest thing they've ever seen in the universe: It's a galaxy far, far away from a time long, long ago.... hosted.ap.org |