When the first human rides into space and reaches 80 miles up, he will hear alarming sounds: the sharp pings of cosmic dust particles hitting the skin of his capsule. Harvard Astronomer Professor Fred L. Whipple last week told an Air Force space conference at San Antonio that the earth is surrounded by a shallow but unexpectedly dense cloud of dust that can be detected only by the noise that it makes when it hits space vehicles equipped with listening devices.
The particles, said Whipple. are extremely small, averaging 300 billion to the ounce. They are thickest 80 miles up. Farther out...
To continue reading:
or
Log-In
