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Mars Orbiter’s Demise Avoidable

by Michael Cabbage of The Sentinel Staff

CAPE CANAVERAL — The sort of mistake usually found in grade-school math homework proved fatal to a $125 million NASA Mars probe.

A NASA investigation released Wednesday confirmed earlier reports that aerospace contractor Lockheed Martin botched the design of critical navigation software for the ill-fated Mars Climate Orbiter. While flight computers on the ground did calculations based on pounds of thrust per second, the spacecraft’s computer used metric system units called newtons. A check to make sure the values were compatible was never done.

The spacecraft was to go into orbit around Mars on Sept. 23, acting as a weather satellite and relaying data to Earth from a sister probe scheduled to land on the Red Planet next month. But the metric mistake caused the Climate Orbiter to drift slowly off course as it fired its rocket engines about a dozen times to stabilize itself during a nine-month, 416-million mile journey. The probe approached Mars at too low an altitude and likely burned up in the planet’s atmosphere.

This picture shows a 1986 test of a Tomahawk Missle that traveled 640km (~400 miles) and detonated over a decommissioned fighter plane.  (Click on picture to enlarge).  If you look closely, especially at the 2nd panel, can you see that the plane is on fire even though the debris from the missile hasn’t reached it yet?  How can that be?

(Thanks to the Bad Astronomy website for this picture and background info!)

My expectations for the year are simple yet far-reaching:

1. Come prepared to class each and every day.
2. Give me your best effort each and every day.
3. Be respectful – to yourself, to your classmates, and to the instructor.
4. Conduct yourself in a professional manner.

The following classroom rules should also be observed:

• No cell phones are to be seen or heard during the entire school day. I will answer and/or confiscate any phone if it is operated or rings in my room. This includes text messaging, taking pictures, or using the phone as a calculator.
• No electronic entertainment devices are to be used during class time.
• No pants are to be worn below the waist line. A belt will be provided to you should you choose not to comply.

Materials needed for this class:

1. Notebook
2. Calculator (scientific)
3. Binder
4. Pen/Pencil
5. Enthusiasm and a positive attitude

Grading Policy

Homework, labs, and tests are all important to success in this class, therefore, each of these components will be weighted equally. I reserve the right to adjust this grading policy as situations warrant throughout the year.

“Three things give the student the possibility of surpassing his teacher: ask a lot of questions, remember the answers, teach.” — Jan Amos Coménius

“Learning is something students do, NOT something done to students.” –Alfie Kohn