Instant · Precise · Universal
28 units available
6 categories total
To convert tropical years to days: multiply by 365.24219. To Julian years: multiply by 365.24219/365.25.
1 tropical year ≈ 365.24219 days ≈ 365 d 5 h 48 min 45 s. Shorter than the sidereal year by about 20 minutes due to precession.
For example, 1 Year (Tropical) (yr (Trop)) = 12.36826592 Month (Synodic) (mo (syn)).
| Year (Tropical) (yr (Trop)) | Month (Synodic) (mo (syn)) |
|---|---|
| 0.1 | 1.236826592 |
| 0.5 | 6.184132962 |
| 1 | 12.36826592 |
| 2 | 24.73653185 |
| 5 | 61.84132962 |
| 10 | 123.6826592 |
| 25 | 309.2066481 |
| 50 | 618.4132962 |
| 100 | 1236.826592 |
| 500 | 6184.132962 |
| 1000 | 12368.26592 |
The tropical year is the time for the Sun to return to the same equinox point — approximately 365.24219 days (31,556,925.216 seconds).
1 tropical year ≈ 365.24219 days ≈ 365 d 5 h 48 min 45 s. Shorter than the sidereal year by about 20 minutes due to precession.
To convert tropical years to days: multiply by 365.24219. To Julian years: multiply by 365.24219/365.25.
Calendar design — the Gregorian calendar's average year (365.2425 days) approximates the tropical year to within 26 seconds.
The tropical year is slowly shortening — by about 0.53 seconds per century. In the year 1900, it was 365.24220 days.
Confusing tropical year with sidereal year — the tropical year is ~20 minutes shorter due to axial precession.
The tropical year governs seasons. If we used the sidereal year for calendars, seasons would slowly drift through the months over ~26,000 years.
The synodic month is the time between two successive new moons — approximately 29.53059 days (2,551,442.976 seconds).
1 synodic month ≈ 29.53059 days ≈ 708.73 hours. Longer than a sidereal month (27.32 days) because Earth also moves in its orbit.
To convert synodic months to days: multiply by 29.53059. To convert to calendar months: multiply by ~0.970.
Islamic calendar months, tidal cycle predictions, menstrual cycle correlations, and astronomical event planning.
The synodic month is ~2.2 days longer than the sidereal month because the Moon must 'catch up' to the same Sun-Earth-Moon alignment as Earth orbits.
Confusing synodic month with calendar month. The synodic month is ~29.5 days, shorter than most calendar months.
Watch the Moon for a full cycle from new moon to new moon — that's one synodic month (~29.5 days).



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