Mars sol
Sol (borrowed from the
A sol is slightly longer than an Earth day. It is approximately 24 hours, 39 minutes, 35 seconds long. A Martian year is approximately 668.6 sols, equivalent to approximately 687 Earth days[1] or 1.88 Earth years.
The sol was adopted in 1976 during the Viking Lander missions and is a measure of time mainly used by NASA when, for example, scheduling the use of a Mars rover.[2][3]
Length
The average duration of the day-night cycle on Mars — i.e., a Martian
Usage in Mars lander timekeeping
When a
Although NASA lander missions to Mars have twice occurred in pairs, no effort was made to synchronize the sol counts of the two landers within each pair. Thus, for example, although Spirit and Opportunity were sent to operate simultaneously on Mars, each counted its landing date as "Sol 1", putting their calendars approximately 21 sols out of sync.
Terminology
The word "yestersol" was coined by the NASA Mars operations team early during the MER mission to refer to the previous sol (the Mars version of "yesterday"), and came into fairly wide use within that organization during the Mars Exploration Rover Mission of 2003.[7] It was eventually picked up and used by the press.[8] Other neologisms include "tosol" (for "today" on Mars), as well as one of three Mars versions of "tomorrow": "nextersol", "morrowsol", or "solmorrow".[9] NASA planners coined the term "soliday" at least as far back as 2012 to refer to days off due to time phasing or the synching of planetary schedules.[10]
Conversion
Considering a possible
For the Spirit mission, a small watchmaker's store created mechanical watches for the mission crew that kept Mars time with no more than 10 seconds difference per Earth-day.[11] In 2022, it was reported that the watchmaker Omega had begun to sell digital-analog hybrid watches to the public.[12]
References
- ^ "Mars' Calendar".
- .
- ^ National Aeronautics and Space Administration. Retrieved 13 June 2018.
- ^ .
- ^ Belloni, Mario; Timberlake, Todd (2014). "Sidereal and Solar Day JS Model". compadre.org. American Association of Physics Teachers.
- ^ "Phoenix Mars Mission - Mission - Mission Phases - On Mars". Phoenix.lpl.arizona.edu. 29 February 2008. Retrieved 13 July 2012.
- ISBN 978-0547822808.
- ^ Chang, Alicia (3 August 2012). "MSL? EDL? A guide to NASA's Mars rover lingo". The Christian Science Monitor. Retrieved 19 June 2020.
Yesterday on Mars is yestersol.
- ^ Martínez-Frías, Jesús (28 September 2002). "Marte: 'yestersol', 'tosol' y 'solmorrow'" [Mars: 'yestersol', 'tosol', and 'solmorrow']. El Mundo (in Spanish). Madrid, Spain: Unidad Editorial S.A. Retrieved 23 April 2014.
- ^ "MSL abbreviations and acronyms". an.rsl.wustl.edu. 31 October 2012. Retrieved 19 December 2015.
- ^ "Watchmaker With Time to Lose". JPL Mars Exploration Rovers. 2014. Retrieved 22 January 2015.
- ^ Pearlman, Robert Z. (2022). "New Omega Marstimer watch keeps time on Earth and the Red Planet". Space.com. Retrieved 3 October 2022.