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Science Challenge #31

Challenge Question #1.
In 1990 the Hubble Space Telescope (HST) was carried into space in the cargo bay of the Space Shuttle Discovery. It was deployed in low Earth Orbit (320 miles above Earth) on April 24. In mid May the first images transmitted from the telescope to Earth were out of focus!. The fault was found to be due to the mirror which was flatter than prescribed.
What was the order of magnitude of the error? Was the mirror 1 inch, .1 inch or .0001 inch too flat?
Challenge Question #2.
On December 11, 1998 NASA launched the Mars Climate Orbiter destined to reach Mars on September 23, 1999. Early in the morning of September 23 the orbiter fired its main engine to go into orbit about 150 kilometers above the planet surface, passed behind Mars as seen from Earth, and was not heard from again. NASA determined that a navigational error resulting from computer data entry of English instead of metric units (eg. pounds instead of newtons) caused the Orbiter to crash into the surface of Mars.
What was the result of the navigational error that caused the crash?
a) Orbiter was in too low an orbit,
b) Orbiter was travelling too fast,
c) Orbiter had not properly acclimated to the environment of space.

Select an Answer

Names of those with correct responses
Question 1. Correct answer received from: kbill, Robert, baliga, non, Chrisana, macaronicheese, Joe, Dean, Jon
Question 2. Correct answer received from: kbill, Robert, Jim, non, Kim M., Vinzana (Youth), russr, trent, macaronicheese, Joe, brenda, r2, Dean, Jon, Zodiac

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