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Quantitative and Technical Material. Most information from Rude, Carolyn. Technical Editing, 4 th ed. http:// www.nasa.gov/images/content/206510main_hstimgMARS_200711218_HI.jpg.
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Quantitative and Technical Material Most information from Rude, Carolyn. Technical Editing, 4th ed. http://www.nasa.gov/images/content/206510main_hstimgMARS_200711218_HI.jpg
The Mars Climate Orbiter was lost at the Red Planet […] because the mission's navigation team was unfamiliar with the spacecraft. It lacked training, and failed to detect a mistake by outside engineers who delivered navigation information in English [imperial] rather than metric units, according to a mission failure investigation report released Wednesday. Image: http://dsc.discovery.com/space/top-10/nasa-disaster-moments/index-06.html A litany of errors and problems led to the loss of the $125 million spacecraft on Sept. 23, a loss that has complicated an upcoming Mars landing mission, the report says. Space.com
The Mission Failure Investigation Board's report cites the following contributing factors: • Errors went undetected within ground-based computer models of how small thruster firings on the spacecraft were predicted and then carried out on the spacecraft during its interplanetary trip to Mars • The operational navigation team was not fully informed on the details of the way that Mars Climate Orbiter was pointed in space, as compared to the earlier Mars Global Surveyor mission • A final, optional engine firing to raise the spacecraft’s path relative to Mars before its arrival was considered but not performed for several interdependent reasons • The systems engineering function within the project that is supposed to track and double-check all interconnected aspects of the mission was not robust enough, exacerbated by the first-time handover of a Mars-bound spacecraft from a group that constructed it and launched it to a new, multi-mission operations team • Some communications channels among project engineering groups were too informal • The small mission navigation team was oversubscribed and its work did not receive peer review by independent experts • Personnel were not trained sufficiently in areas such as the relationship between the operation of the mission and its detailed navigational characteristics, or the process of filing formal anomaly reports • The process to verify and validate certain engineering requirements and technical interfaces between some project groups, and between the project and its prime mission contractor, was inadequate Quoted directly from MFIB's report overview
Basic Guidelines for the Use of Numbers: • Use figures for all quantifiable units of measure • Do not begin a sentence with a figure • Do not mix systems of measurement • Set decimal fractions of less that 1.0 with an initial zero • Convert treatment of numbers in a translation
Fractions Built up Solid (Inline) [1 + (x – 3)] / (y + 2) 1 + (x - 3) y + 2 To mark a fraction for inline presentation: 1 2 Pay attention to order of parentheses, brackets, and braces: {[()]}
Equations • Equations are statements, read as sentences, which follow accepted rules of grammar • Equations contain an equal (=) sign • Equations are numbered sequentially, generally by chapter, then equation # (1.1, 2.3, etc.) • If you must break an equation across a line, break in front of an operational sign or relation. Never break terms in a parentheses.
Formatting Equations • Align related equations on the equal sign • Set operational or relational signs with a space on either side • Place a zero before a decimal in quantity less than 1, except for correlation coefficients (r) and probabilities (P) • Capitalize experiment and trial when these words refer to specific tests
Praesentvariusnibh in sapienaliquetpulvinar. Mauriselementumestnecdiamconsequat sit amettristique ante auctor. Donecluctustinciduntsapienquisconvallis, such as the equation for Tangential Velocity: (1) Proinmalesuadapellentesqueeuismod. Aeneanquismalesuadalectus. Phasellusmollissuscipit dui, a tempus semvolutpat et. Acceleration is satisfied by (1.2)
Praesentvariusnibh in sapienaliquetpulvinar. Mauriselementumestnecdiamconsequat sit amettristique ante auctor. Donecluctustinciduntsapienquisconvallis, such as the equation for Tangential Velocity: (1.1) Proinmalesuadapellentesqueeuismod. Aeneanquismalesuadalectus. Phasellusmollissuscipit dui, a tempus semvolutpat et. Acceleration is satisfied by (1.2)
