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40 tons: the weight of the door to NASA’s Chamber A, a room that recreates the deadly conditions of deep space and, because it can reach 11 Kelvin, is the coldest place on Earth
4: the number of spiral arms that make up the Milky Way, according to a new study (previous observations give our galaxy just two arms)
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1 trillionth of a second: the time it should take scientists to heat water to 600 degrees Celsius using a clever new heating method
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$11,720: the money raised via Indiegogo for an absurd device that claims to translate dog thoughts into English
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$2 million: the top prize of the DARPA Robotics Challenge, a Pentagon-funded competition to develop robotic first responders
$1 million: the prize the Methuselah Foundation is offering the the first research group to make a bioengineered liver
2 centimeters: the average amount of space between penguins in a huddle, according to researchers who created a mathematical model of penguin huddles
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1.2 million: the estimated number of Americans who get salmonella infections each year (but don’t worry, your eggnog is safe)
$199: the price of the Canary home security system, which includes a wide-angle HD camera, infrared motion sensor, temperature and humidity sensors, and microphone
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1903: the year the Wright brothers first piloted a heavier-than-air craft. Read the story of their famous first flight in the September 1925 issue of Popular Science.
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1976: the year of the last soft landing on the moon, until China’s Chang’e 3 spacecraft touched down last week (video)
14,838: the number of pieces of large debris orbiting Earth (see where they are)
10 kilowatts: the power of a recently tested, truck-mounted Army laser that can zap incoming drones and mortar shells
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