# Mariner 1

Mission type Launch of Mariner 1 Venus flyby NASA / JPL 4 minutes, 53 secondsFailed to orbit Mariner[source?]based on Ranger Block I Jet Propulsion Laboratory 202.8 kilograms (447 lb) 220 watts (at Venus encounter) July 22, 1962, 09:21:23 UTC Atlas LV-3 Agena-B Cape Canaveral LC-12 Mariner

Mariner 1 was a NASA spacecraft. It was the first spacecraft in the Mariner program. Mariner 1 was planned to do a Venus fly-by. However, it was destroyed by the Range Safety Officer 293 seconds after launch. It was destroyed because the rocket moved off course and was a safety risk. Mariner 1 was followed by Mariner 2.

## Why it was destroyed

The Atlas-Agena rocket was controlled by a hand-written formula:

${\displaystyle {\bar {{\dot {R}}_{n}}}}$

Which means "the nth smoothed value of the time derivative of a radius R". However, for this mission, an overline (‾) was missing in the formula, which looks something like this:

${\displaystyle {\dot {R}}_{n}}$

Because the smoothing function was missing, the rocket became sensitive at minor changes. Then, the rocket became out of control and destroyed by the Range Safety Officer.[1][2][3] Few years later, Arthur C. Clarke wrote that Mariner 1 was "wrecked by the most expensive hyphen in history".[4]

## References

1. Neumann, Peter (May 27, 1989). "Mariner I – no holds BARred". Risks Digest. Retrieved October 21, 2014.
2. Ceruzzi, Paul E. Ceruzzi (1989). Beyond the Limits: Flight Enters the Computer Age. ISBN 978-0262530828.
3. "Planetary Probe History". Space FAQ. August 2013. Retrieved September 9, 2016 – via FAQs.org.
4. The Promise of Space, Arthur C. Clarke, 1968, p. 225.