День

Структура

Сколько часов в сутках на марсе?

Почти любая книга по астрономии скажет вам что период вращения марса 24,6229 часа или 24 часа и 37 минут. Хотя, надо иметь в виду что эта же таблица определяет период вращения земли в 23 часа и 56 минут. Разве земные сутки не 24 часа? Куда пропали 4 минуты? Разница в том что 23 часа и 56 минут это звёздные сутки, то есть период вращения земли измеряется с точки зрения стационарного ориентира. В то время как земля вращается вокруг своей оси она также продвигается по своей орбите вокруг солнца и положение земли по отношению к солнцу слегка изменяется. 4 минуты занимает у земли повернуться на этот дополнительный угол и поэтому земные сутки измеряемые с точки зрения солнца 24 часа.

Тот же принцып прилагается к марсу. Хотя звёздные сутки 24 часа и 37 минут, солнечные сутки 24 часа, 39 минут, 35,24409 секунд (88775,24409 секунд).

Table Table of Clocks

How many primary divisions should there be to the Martian day?

General

8 Primary Divisions

Several 8-hour systems have been proposed.

Pro

Con

The number 8 has few factors, being uniquely divisible by only 2 and 4.

10 Primary Divisions

Several 10-hour systems have been proposed.

Pro

Dividing the day by 10 is the first step of a decimal or "metric" clock.

Con

The number 10 has few factors, being uniquely divisible by only 2 and 5.

12 Primary Divisions

The only system in this category divides the day into successively higher powers of 12 up to 125. The system's basic unit equals 0.35677 standard seconds.

Pro

Con

16 Primary Divisions

Several 16-hour systems have been proposed.

Pro

Con

20 Primary Divisions

Several 20-hour systems have been proposed.

Pro

Con

24 Primary Divisions

Several 24-hour systems have been proposed.

Pro

Retaining the 24-hour system that is used on Earth is the most conservative approach. The number 24 has many factors, being divisible by 2, 3, 4, 6, 8, and 12.

Con

24 or 25 (Earth hour algorithm) Primary Divisions

The only system in this category adds an hour approximately twice every three days to account for the additional 39 minutes 35.2 seconds in a Martian day.

Pro

The system is based on the standard Earth second.

Con

Given the number of people who complain about switching between standard time and "daylight saving" or "summer" time twice a year, adding a hour twice every three days would be very disorienting.

Source Documents:
Document Martian Calendar
Anton Sherwood

25 Primary Divisions

Several 25-hour systems have been proposed.

Pro

Con

The number 25 is a perfect square, thus it is only uniquely divisible by 5. There is no identified social use for dividing the day by 5.

30 Primary Divisions

The only system in this category is 74 minutes per hour, 40 seconds per minute.

Pro

This system retains the standard Earth second as the basic unit of time.

Con

The system requires setting the clock back one hour every 180 days.

32 Primary Divisions

The only system in this category is 40 minutes per hour, 40 seconds per minute. The system's basic unit equals 1.73384 standard seconds.

Pro

Con

37 Primary Divisions

Several 37-hour systems have been proposed.

Pro

Con

The number 37 is prime.

60 Primary Divisions

Several 60-hour systems have been proposed.

Pro

The number 60 has many factors, being divisible by 2, 3, 4, 5, 6, 10, 12, 15, 20, and 30.

Con

100 Primary Divisions

The only system in this category is 100 units per day with no secondary units. However, chronometers would display to three decimal places. The system's basic unit equals 887.752 standard seconds.

Pro

This is a thoroughly decimal time system, being based only on powers of 10.

Con

The number 10 has few factors, being uniquely divisible by only 2 and 5.

Source Documents:

Document A New Calendar and Clock for the Planet Mars
Manfred Krutein

1000 Primary Divisions

The only system in this category is 1000 minutes per hour. The system's basic unit equals 0.0887752 standard seconds.

Pro

  • This is a thoroughly decimal time system, being based only on powers of 10.

  • Avoids confusing differentiation between "Earth seconds/minutes/hours" and "Martian seconds/minutes/hours" by using a completely different nomenclature.

  • Ought to be reasonably intuitive for metric system users, particularly scientists.

  • Millisols are close enough (in length) to minutes to allow for fairly straightforward conversions when necessary.

Con

  • The number 10 has few factors, being uniquely divisible by only 2 and 5.

  • Confusing to new arrivals or visitors who are used to minutes/hours/seconds.

Source Documents:

Document The Areosynchronous Calendar
Shaun Moss
Document Martian Dreams Time System
Linda Naughton and Robert O'Meara

What pattern of smaller divisions should there be to the Martian day?

For 8 primary divisions:

General

8:8:8:8:8:8

The system's basic unit equals 0.33864 standard seconds.

Pro

Con

Source Documents:

Document Martian Time Keeping
Damon Dean

8:300:37

Pro

This system retains the standard Earth second as the basic unit of time.

Con

The total number of seconds in this clock is 88,800, which is 24.8 more than a Martian day, thus the system requires "skip minutes" to be subtracted from the day on a regular basis.

The number 37 is prime.

For 10 primary divisions:

General

10:50:20

The system's basic unit equals 8.87752 standard seconds.

Pro

Con

Source Documents:

Document Excerpts from The Gods of Mars and The Warlord of Mars
Edgar Rice Burroughs

10:100:100

The system's basic unit equals 0.887752 standard seconds.

Pro

This is a thoroughly decimal time system, being based only on powers of 10.

Con

The number 10 has few factors, being uniquely divisible by only 2 and 5.

Source Documents:

Document The Darian System
Thomas Gangale
Document Le Calendrier Martien
Olivier Prud'homme
Document The Martian Calendar
M. Vertregt
Document Martian Year Revisited
M. Vertregt and Francis Graham

For 16 primary divisions:

General

16:16:16:16

The system's basic unit equals 1.35460272 standard seconds.

Pro

Computers would be very happy... well, the AI ones at least.

Hex evaluation = 0xF : 0xF : 0xF : 0xF

One day = 0xFFFF (65536) Mecs or 2^16 power ( 2 bytes ) 

                0xFFF  (4096)  Mytes
                0xFF    (256)  Mims
                0xF      (16)  Mours

16 Mecs in a Myte;  16 Mytes in a Mim;  16 Mims in a Mour;  16 Mours in a Sol
(21.67 Earth sec)   (5.78 Earth min.)   (92.47 Earth min.)  (1 Martian day)

Con

16:150:37

The system's basic unit equals 1.00 standard seconds.

Pro

This system retains the standard Earth second as the basic unit of time.

Con

The total number of seconds in this clock is 88,800, which is 24.8 more than a Martian day, thus the system requires "skip minutes" to be subtracted from the day on a regular basis.

For 20 primary divisions:

General

20:50:100

The system's basic unit equals 0.887752 standard seconds.

Pro

This is a modified "metric" clock. The basic unit is 1/100,000 of a day. The minute is 1/1000 of a day or "milliday." The division of the minute is based on a power of 10. The hour is provided as a familiar "human" unit of time.

Con

The number 10 has few factors, being uniquely divisible by only 2 and 5. The number 25, being a perfect square, has only one unique factor.

Source Documents:

Document Martian Clock and Calendar
Mickey D. Schmidt

20:74:60

The system's basic unit is the standard second.

Pro

This system retains the standard Earth second as the basic unit of time.

Con

The system requires setting the clock back one hour every 180 days.

Source Documents:

Document Martian Clock using Standard Seconds
Dale Shultz

For 24 primary divisions:

General

24:10:370

The system's basic unit is the standard second.

Pro

This system retains the standard Earth second as the basic unit of time.

Con

The total number of seconds in this clock is 88,800, which is 24.8 more than a Martian day, thus the system requires "skip minutes" to be subtracted from the day on a regular basis.

24:10:1000

The system's basic unit equals 0.369897 standard seconds.

Pro

The divisions of the hour and minute are based on powers of 10.

The minutes on this clock are about 6.165 earth-minutes long. The 5-minute interval has proven to be such a comfortable length of time, that we rarely tell time in smaller intervals here on Earth, and we usually even take the extra effort to round to the nearest 5 or 15. When necessary, greater precision is accommodated by dividing the minute into 1000 seconds.

The format for this clock is hh:m:sss. "12:5" is clearly distinguishable from an Earth time, such as "12:30"). On Earth, 4:10 could mean either 4 hours 10 minutes, or 4 minutes 10 seconds. But with this Metric clock, you can clearly distinguish them by number of digits, since each field has a different number of digits.

Con

The number 10 has few factors, being uniquely divisible by only 2 and 5.

Source Documents:
Document Martian Semi-Metric Clock
Alan Hensel

24:60:43

The system's basic unit equals 1.433709 standard seconds.

Pro

Con

Source Documents:
Document Time on Mars
John J. G. Savard

24:60:57

The system's basic unit equals 1.081570 standard seconds.

Pro

Con

Source Documents:
Document Time on Mars
John J. G. Savard

24:60:60

The system's basic unit equals 1.027491 standard seconds. It retains the same units relationship as in an Earth clock.

Pro

The Martian day is only 2.7 percent longer than an Earth day, hardly enough for a person to notice. Similarly, stretching the familiar terrestrial units of time makes for a system to which people could most easily adapt. The system already has historical precedent, having been used by JPL Viking and Pathfinder project personnel during operations on the Martian surface.

Con

Source Documents:
Document Time on Mars
Michael D. Allison and Robert B. Schmunk
Document The Darian System
Thomas Gangale
Document Time Keeping on Mars
Alan Dechert
Document The Fortieth of July
Pierre Hallet
Document An Easily Understood Calendar and Time System for Mars
Leon G. Heron
Document Rationale for the Martian Calendar's Structure
Bill Hollon
Document MarsView
Joe Knapp
Document Martian Calendar
Roger E. Kuiper
Document It's About Time
I. M. Levitt
Document Mars Clock and Calendar
I. M. Levitt
Document Excerpts from Guide to Mars
Patrick Moore
Document The QS Calendar
Jelmer Oosthoek
Document Martian Clock and Calendar
Mickey D. Schmidt
Document Welcome to Mars
Frank Sorenson
Document An Explanation of Zubrin's Mars Calendar
Paul J. Thomas
Document Options for Martian Timekeeping
William Woods
Document A Calendar for Mars
Robert Zubrin
Document A Calendar for the Planet Mars
Robert Zubrin

24:60:60 + 00:39:35.244

The system's basic unit is the standard second. A period of 39 minutes 35 seconds is appended to each 24-hour day.

Pro

This system retains the standard Earth second as the basic unit of time, and also retains the basic pattern of 24 hours per day and 60 minutes per hour. A second is the basis for measurement in so many scientific, technical, and medical procedures and equipment. We should preserve this link with Earth and its people. The people of Mars may decide later whether equipment, tables, and such should be modified.

Con

This system divides the Martian day unequally. The system would be difficult to coordinate among several distant locations on Mars, where the "time slip" would occur at different times. Since there is a fractional number of Earth seconds in a Martian day, the system requires "leap seconds" to be added to the day on a regular basis.

Source Documents:
Document Excerpts from Red Mars
Kim Stanley Robinson
Document Martian Timekeeping
Anders Ström

24:(60:60 + 01:38 or 01:39)

The system's basic unit is the standard second. Each hour has 99 seconds, counted independently of the other minutes and seconds of the hour, appended to it after the last second of the last minute of the hour. This is to accommodate the longer Martian sol. Since the actual time needed to be appended is 98.9685 seconds, an excess of about 500 seconds will have to be eliminated by not appending all or some of the 99 seconds to a few hours each Martian year. The deducted amount is dependent upon the number of sols in the calendar year.

Pro

This system preserves a 24:60:60 clock using the standard second. For most civilian purposes scheduling to the second is not necessary and most Earth digital clocks do not display the second. Where accuracy to the second is required, Martian clock and watch displays can be enhanced to include a counter for the additional minute and 39 seconds added each hour. Standard Earth display of time in HH:MM:SS and use of Earth nomenclature for time can be used, providing one can live with ignoring the extra 99 seconds between hours.

Con

24:60:(61 or 62)

The system's basic unit is the standard second. An algorithm is required to determine whether a given minute contains 61 or 62 seconds.

Pro

This system retains the standard Earth second as the basic unit of time, and also retains the basic pattern of 24 hours per day and 60 minutes per hour. A second is the basis for measurement in so many scientific, technical, and medical procedures and equipment. We should preserve this link with Earth and its people. The people of Mars may decide later whether equipment, tables, and such should be modified.

Con

This system requires a complex algorithm to determine which particular minute contains 61 or 62 seconds. The system would be difficult to coordinate among several distant locations on Mars, where the added second would occur at different times. Since there is a fractional number of Earth seconds in a Martian day, the system requires "leap seconds" to be added to the day on a regular basis.

Source Documents:
Document Excerpts from Martian Rainbow
Robert L. Forward
Document Martian Clock and Calendar
Mickey D. Schmidt

24:60:61.64947506

The sol is divided into 24 major units (Martian equivalent of hours), which are in turn divided into 60 smaller units lasting 61.64947506 SI seconds (based on a value of 88775.24409 seconds for the sol). Expressed in Terran units, the "Martian hour" lasts 61.64947506 minutes, or 1 hour 1 min and 38.9685036 seconds. Clocks that display only Martian hours and minutes look exactly like Terran clock. Clocks that display seconds use the format 24:60:62 (i.e. display resets to zero at midnight after reaching 23:59:61).

Pro

Given that the second is almost never used in social and business schedules, and that many clocks do not display seconds anyway, the system will feel identical to the terrestrial clocks to most users.

No leap seconds or timeslips are needed. Time is counted continuously throughout the sol. Time-based calculations and unit conversions can be done essentially as on Earth, except that the factor 61.64947506 is used instead of 60 when converting between Martian “minutes” and seconds.

Keeping the SI second means that other units and constants derived from it (Hz, G, c, definition of the meter etc…) are the same on Mars and Earth. Physics textbooks and computer software don't need extensive rewriting on Mars.

The same method, i.e. stretching or shrinking the minute to express it in a decimal number of SI seconds) can be used to generate clock systems that use the second on other planets or satellites, not just Mars.

Con

Having to remember and use the number 61.64947506.

24:60:92

The system's basic unit equals 0.670103 standard seconds.

Pro

Con

Source Documents:
Document Time on Mars
John J. G. Savard

24:60:100

The system's basic unit equals 0.616494 standard seconds.

Pro

Con

Source Documents:
Document Time on Mars
John J. G. Savard
Document Options for Martian Timekeeping
William Woods

24:100:100

The system's basic unit equals 0.369897 standard seconds.

Pro

The divisions of the hour and minute are based on powers of 10.

Con

The number 10 has few factors, being uniquely divisible by only 2 and 5.

Source Documents:
Document Options for Martian Timekeeping
William Woods

For 25 primary divisions:

General

25:40:100

The sol is divided into 25 major units (Martian equivalent of hours), which are in turn divided into 40 smaller units (millisols) lasting 88.77524409 SI seconds. Expressed in Terran units, the length of the "martian hour" is 59 minutes and 11.0097636 seconds. Clocks use the format 25:40:89 (i.e. display resets to zero at midnight after reaching 24:39:88). Noon (boundary between “am” and “pm”) is at 12:20:00.

Pro

No leap seconds or timeslips are needed. Time is counted continuously throughout the sol.

The major unit is almost the same length as the Terran hour.

This is a partially "metric" clock. The smaller unit (stretched minute) is 1/1000 of a day or "millisol" A quarter of the major unit is 1/100 of a day or "centisol."

Time-based calculations and unit conversions can be done essentially as on Earth, except that the factor 88.77524409 is used instead of 60 when converting between minutes and seconds.

Keeping the SI second means that other units and constants derived from it (Hz, G, c, definition of the meter etc..) are the same on Mars and Earth. Physics textbooks and computer software don't need extensive rewriting on Mars.

The same method, i.e. stretching or shrinking the minute to express it in a decimal number of SI seconds) can be used to generate clock systems that use the second on other planets or satellites, not just Mars.

Con

Having to remember and use the number 88.77524409 when converting millisols into seconds.

The number 25 can only be divided by 5.

25:40:100

The system's basic unit equals 0.887752 standard seconds.

Pro

This is a modified "metric" clock. The basic unit is 1/100,000 of a day. The minute is 1/1000 of a day or "milliday." The division of the minute is based on a power of 10. The hour is provided as a familiar "human" unit of time, while a quarter of an hour is 1/100 of a day or "centiday."

Con

The number 10 has few factors, being uniquely divisible by only 2 and 5. The number 25, being a perfect square, has only one unique factor.

Source Documents:

Document Metric Time for Mars
Bruce A. Mackenzie

25:50:71

The system's basic unit equals 1.000284 standard seconds.

Pro

Con

The number 71 is prime.

25:53:67

Pro

This system retains the standard Earth second as the basic unit of time, and also retains the basic pattern of 24 hours per day and 60 minutes per hour.

Con

The total number of seconds in this clock is 88,775, which is 0.2 less than a Martian day, thus the system requires "leap seconds" to be added to the day on a regular basis.

The numbers 53 and 67 are both prime.

Source Documents:

Document SCDTL Calendar and Clock for Mars
Lance Latham

25:60:60

The system's basic unit equals 0.986391 standard seconds.

Pro

Con

25:100:100

The system's basic unit equals 0.355101 standard seconds.

Pro

Con

For 37 primary divisions:

General

37:8:300

Pro

This system retains the standard Earth second as the basic unit of time.

Con

The total number of seconds in this clock is 88,800, which is 24.8 more than a Martian day, thus the system requires "skip minutes" to be subtracted from the day on a regular basis.

The number 37 is prime.

37:10:240

Pro

This system retains the standard Earth second as the basic unit of time.

Con

The total number of seconds in this clock is 88,800, which is 24.8 more than a Martian day, thus the system requires "skip minutes" to be subtracted from the day on a regular basis.

The number 37 is prime.

37:40:60

Pro

This system retains the standard Earth second as the basic unit of time.

Con

The total number of seconds in this clock is 88,800, which is 24.8 more than a Martian day, thus the system requires "skip minutes" to be subtracted from the day on a regular basis.

The number 37 is prime.

Source Documents:

Document Martian Clock using Standard Seconds
Dale Shultz

For 60 primary divisions:

General

60:60:60

The system's basic unit equals 0.410996 standard seconds.

Pro

Con

Source Documents:
Document Options for Martian Timekeeping
William Woods

60:100:10

The system's basic unit equals 1.479587 standard seconds.

Pro

The divisions of the hour and minute are based on powers of 10.

Con

The number 10 has few factors, being uniquely divisible by only 2 and 5.

Source Documents:
Document Options for Martian Timekeeping
William Woods

60:100:100

The system's basic unit equals 0.147959 standard seconds.

Pro

The divisions of the hour and minute are based on powers of 10.

Con

The number 10 has few factors, being uniquely divisible by only 2 and 5.

Source Documents:
Document Options for Martian Timekeeping
William Woods