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Near Earth Asteroid 'Florence' Makes a Close Pass (space.com)

kbahey writes: A big, bright, near-Earth asteroid, known as 3122 Florence, made a safe fly by Friday night. Florence is classified as a Potentially Hazardous Object. At its closest, it was about 7 million km (4.4 million miles) away from earth. It is still visible in amateur telescopes over the next few days where it would be seen to move over several minutes against the background stars. It can be located using this map. According to NASA officials, the asteroid hasn't been this close to Earth since 1890, and it won't be this close again until 2500. "Asteroid 3122 Florence was discovered in 1981 by astronomer Schelte 'Bobby' Bus at the Siding Spring Observatory in Australia," reports Space.com. "The asteroid is named in honor of Florence Nightingale (1820-1910), who pioneered modern nursing, NASA officials said in a separate statement."

2 of 105 comments (clear)

  1. And statistics... by jandersen · · Score: 4, Informative

    The asteroid is named in honor of Florence Nightingale (1820-1910), who pioneered modern nursing

    Indeed, Nightingale is described as "a true pioneer in the graphical representation of statistics", and is credited with developing a form of the pie chart now known as the polar area diagram,[53] or occasionally the Nightingale rose diagram...

  2. Re:That's nothing... by rgbatduke · · Score: 4, Informative

    Asteroids will hit the Earth (if at all) at LEAST at 11.2 km/sec, as they have greater than escape energy relative to the Earth's gravitational field. That's 11.2 kilometers per SECOND, or a bit over 40,000 kilometers per HOUR. The energy released is greater than 64 million joules per kilogram of rock (escape energy). So if you take a (say) 2.5 km ball of rock (5 km in diameter), roughly estimate its mass as 4 times r^3 you get 4 e+18 joules. Convert this to tons of TNT and you get roughly a teraton. The total explosive energy of the entire nuclear arsenal of the Earth is less than 7 gigatons (including reserve weapons -- only around 1 GT is on delivery vehicles almost all of this belonging to the US and Russia). The biggest explosion in recorded history was the explosion of Tambora in 1815, estimated at 33 GT. This is then equivalent in crude terms to over 100 times the entire global arsenal nuclear and conventional, or over 30 times the explosive power of the largest explosion in recorded history, one that altered global climate for close to a decade. Or GREATER.

    I'm not sure "hit by a bus" is an apropos metaphor.

    --
    Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.