Calendar Description - Scheme mjd
The Modified Julian Day calendar is a variation of the Julian Astronomical Day. It is more convenient when referencing recent dates as it requires fewer digits. The day starts at midnight, in contrast to the Julian Astronomical Day where it starts at midday.
Because this calendar scheme has limited historical value, its visibility is set at hidden.
Use Case
There is no known historical use of calendar, although the Julian Day scheme, on which it is based, has been in use by the scientific community, particularly astronomers, for many years.
Definition
Days start at midnight.
The Record consists of a single Field named day.
Record |
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day |
The Modified Julian Day calendar is equal to the Julian Day Number jdn - 2400001.
mjd | day |
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1 |
jdn | day |
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2400002 |
Formats
The formats supplied with this scheme.
Formats - Grammar d | |||||
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Code | Rule | Pseudo:in | Pseudo:out | Example | Note |
d | text | day | dddd | 50138 | D |
def | text | day | dddd | 50138 | H |
u | unit | 9d | 9d | 50138d | H |
Notes: D = Default, H = Hidden. Example based on jdn# 2450139 |
Script
Script - Module hics:jdn |
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scheme mjd { name "Modified Julian Day"; base jdn epoch:2400002; grammar d; visible no; } |
It uses the grammar "d" day count definition from jdn Julian also in the module hics:jdn.