NASA Mars Mission Faces Setback After Heat Shield Cracks Under Pressure : The Two-Way The heat shield, made of material that is as light as balsa wood but can withstand temperatures of nearly 4,000 degrees Fahrenheit, broke during testing earlier this month.
Source: npr.org
Key technologies include a compact pre-cooler heat-exchanger that can take an incoming airstream of over 1,000C and cool it to -150C in less than 1/100th of a second. This would permit Sabre to use oxygen direct from the atmosphere for combustion instead of carrying it in a tank with the weight penalty that implies.
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New results from a decades-old experiment were initially touted as further evidence for dark matter. But independent scientists have cast serious doubt on that claim, leaving most everyone puzzled.
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