Decimal Time - Scientific Decimal Time

Scientific Decimal Time

Scientists often record (rather than observe) time as decimals. For example, decimal days divides the day into 10 equal parts, and decimal years divides the year into 10 equal parts. Decimals are easier to plot than both (a) minutes and seconds, which uses the Sexagesimal numbering system, (b) hours, months and days, which has irregular month lengths. In astronomy, the so-called Julian Day uses decimal days centered on noon.

Decimal seconds in a decimal minute

Since there are 60 seconds in a minute, a tenth part represents 60/10 = 6 seconds.

Conversion between decimal minutes seconds
Decimal Minutes 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Second 6s 12s 18s 24s 30s 36s 42s 48s 54s 60s
Decimal minutes in an decimal hour

Since there are 60 minutes in an hour, a tenth part represents 60/10 = 6 minutes.

Conversion between decimal hours and minutes
Decimal Hours 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Minutes 6m 12m 18m 24m 30m 36m 42m 48m 54m 60m
Decimal hours in a decimal day

Since there are 24 hours in a day, a tenth part represents 24/10 = 2.4 hours (2 hours and 24 minutes).

Conversion between decimal day, and, Hours and minutes
Decimal Days 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Hours:Minutes 2h 24m 4h 48m 7h 12m 9h 36m 12h 14h 24m 16h 48m 19h 12m 21h 36m 24h
Decimal months in a year

Since there are about 365 days in a year, there are about 365/10 = 36.5 days in a tenth of a year. Hence the year 2000.5 represents the day 2 July 2000. More exactly, a year is 365.25 days long, so a tenth of the year is 36.525 days (36 days, 12 hours, 36 minutes).

Conversion between decimal years, and, Date
Decimal Years 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Days 36.525 73.050 109.575 146.100 182.625 219.150 255.675 292.200 328.725 365.250
Date
Time
5 Feb
12:36
14 Mar
1:15
19 Apr
13:48
26 May
2:24
1 Jul
15:00
7 Aug
3:45
12 Sep
16:12
19 Oct
4:48
24 Nov
17:24
1 year
In leap years, all days after 28 Feb occur one day earlier

Read more about this topic:  Decimal Time

Famous quotes containing the words scientific, decimal and/or time:

    My mind is just as open as it ever was, professor. But it’s a scientific mind, and there’s no place in it for superstitions.
    Garrett Fort (1900–1945)

    It makes little sense to spend a month teaching decimal fractions to fourth-grade pupils when they can be taught in a week, and better understood and retained, by sixth-grade students. Child-centeredness does not mean lack of rigor or standards; it does mean finding the best match between curricula and children’s developing interests and abilities.
    David Elkind (20th century)

    From time to time there appear on the face of the earth men of rare and consummate excellence, who dazzle us by their virtue, and whose outstanding qualities shed a stupendous light. Like those extraordinary stars of whose origins we are ignorant, and of whose fate, once they have vanished, we know even less, such men have neither forebears nor descendants: they are the whole of their race.
    —Jean De La Bruyère (1645–1696)