You gotta be kidding me..
You might be thinking that this post is hilariously stupid, of course a year is the revolution of the earth in the sun or exactly 365 and 1/4 days. Well somehow that's true, but somehow it's also incorrect in some sense. There are different types of years with different length for each years, the most common is the Tropical Year (which is the basis for most calendars) but there are more kinds of years not just two or three, but more than five excluding the other planet's year (Martian/Uranian Year).
Most of our calendars uses the Tropical Year or the Solar Year and it is also the kind of year that you know since elementary, and if you forgot what it is, Tropical Year is the total time it takes for the Sun to return to the same position in the cycle of seasons or period of time from vernal equinox to vernal equinox and summer solstice to summer solstice, the exact length of one (1) Tropical Year is 365.242 Days or 365 days, 5 hours, 48 minutes, 45 seconds.
What about Sidereal? Well Sidereal Year is the amount of time it takes for the earth to complete one revolution with respect to fixed stars (One of the most popular fixed star is the Sun itself). One Sidereal Year is equal to 365.256 Earth Days or 365 days,6 hours 9 minutes, 9.76 seconds and if you're not happy with those conversion it is 1.00003878 Tropical/Solar Year.
Another kind of year is the Anomalistic Year, it is defined as the revolution of Earth to the sun with respect to its apsides, well you might be wondering what in seven hell is an apsides. Apsides are the extreme points of the Earth's Orbit (Since Earth's orbit is elliptical), apsides are the Farthest (Aphelion) and Closest (Perihelion) distance of the Earth to the Sun. An Anomalistic Year is defined by the Perihlion Passage or the closest point of the Earth to the Sun. Anomalistic Year is not fixed however, but the average length of one Anomalistic Year is approximately 365.260 Earth Days or 365 days, 6 hours, 13 minutes, 52.6 seconds.
Relax! We're not done yet, I mean I'm not done yet making you feel bad that what you learned in highschool and even in college is somewhat inaccurate or incomplete! To complete your total confusion about these kinds of years I'll give the other kinds of years, but don't worry most of them are not that important and just for educational purpose.
Julian Year - This is the unit used for Astronomy, A Julian Year is defined as 365.25 days or 86,400 SI Seconds, and most of us only know this kind of year since we started learning things. the Julian Calendar that we use today is based on Julian Years, but what about Tropical Years?
To make things clearer, Julian Year does not follow anything, unlike the other years that counts the time span with respect to different things. However, Julian Year was intended to approximate the Tropical Year, since a tropical year was a few minutes shorter than 365.25 days, it's like rounding it off. If we use the Tropical Year for our calendars (which is the accurate measurement rather than Julian Year) we will gain about three (3) days every four centuries (Today we use the Leap Year System or one day every four years).
Draconic/Eclipse Year - The revolution of Sun with respect to the Lunar Node. One Draconic Year is equal to 346.620 Earth Days or 346 days 14 hours 52 minutes 54 seconds.
Full Moon Cycle - Complete Revolution of the Sun with respect to the perigee of Moon's Orbit. A Full Moon Cycle is 411.784 Earth Days or 411 days 18 hours 49 minutes 34 seconds.
Lunar Year - This is defined as the twelve full cycles of the Moon's Phases, Muslim's Calendars is based on Lunar Year and Ramadan is also based on this one. A Lunar Year is approximately 354.37 days.
Besselian Year - The Besselian year was named after Friedrich Bessel, a German Astronomer. A Besselian Year starts when the Sun raches 280° of ecliptic longitude. To calculate for the Besselian Year you can use this equation:
Besselian Year = 1900.0 + (Julian date in Terrestrial Time Scale/Ephemeris Time − 2415020.31352) / 365.242198781
Sothic Year - The interval between heliacal risings of a star Sirius (Current Northern Star) is called a Sothic Year. The duration of one Sothic Year is extremely close to a Julian Year (365.25 Days).
Heliacal Year - This is the interval between the heliacal risings of a star, while it is almost identical to a Sothic Year, a Heliacal Year doesn't have a specific star for its identification where a Sothic Year is based on the Sirius only.
Vague Year - Also known as annus vagus (don't laugh please), this system is mainly used in the calendars of Ancient Egypt, Armenia, Mesoamerica and Iran. This is defined as the approximation to the year equaling 365 days, typically a vague year is divided in 12 months with 30 days each plus 5 epagomenal days (days within a solar calendar that are outisde any regular month).
Gaussian Year - The Gaussian year is the sidereal year for a planet of negligible mass (relative to the Sun) and unperturbed by other planets that is governed by the Gaussian gravitational constant. Such a planet would be slightly closer to the Sun than Earth's mean distance. One Gaussian Year is 365 days, 6 hours, 9 minutes, 56 seconds or 365.256 days.
Well I guess I ran out of source for other kinds of years, you can try including other years of your favorite game or show maybe 1 San Andreas Year or 1 Pokemon Year. Since the Full Moon Cycle is the longest year among them all you can use it in tough situation like on those projects that you need to complete at the end of the year, just say "I'm using the Full Moon Cycle Year System" then point them out to this article.
Disclaimer: I (SalbagSanting) do not take responsibility to any problem that may arise from using a different system other than the Tropical Year/Lunar Year.
Source(s):
Written by SalbagSanting of Red Masterminds
You might be thinking that this post is hilariously stupid, of course a year is the revolution of the earth in the sun or exactly 365 and 1/4 days. Well somehow that's true, but somehow it's also incorrect in some sense. There are different types of years with different length for each years, the most common is the Tropical Year (which is the basis for most calendars) but there are more kinds of years not just two or three, but more than five excluding the other planet's year (Martian/Uranian Year).
Tropical, Sidereal and Anomalistic Year
What about Sidereal? Well Sidereal Year is the amount of time it takes for the earth to complete one revolution with respect to fixed stars (One of the most popular fixed star is the Sun itself). One Sidereal Year is equal to 365.256 Earth Days or 365 days,6 hours 9 minutes, 9.76 seconds and if you're not happy with those conversion it is 1.00003878 Tropical/Solar Year.
Another kind of year is the Anomalistic Year, it is defined as the revolution of Earth to the sun with respect to its apsides, well you might be wondering what in seven hell is an apsides. Apsides are the extreme points of the Earth's Orbit (Since Earth's orbit is elliptical), apsides are the Farthest (Aphelion) and Closest (Perihelion) distance of the Earth to the Sun. An Anomalistic Year is defined by the Perihlion Passage or the closest point of the Earth to the Sun. Anomalistic Year is not fixed however, but the average length of one Anomalistic Year is approximately 365.260 Earth Days or 365 days, 6 hours, 13 minutes, 52.6 seconds.
Yay! Atleast they're just three different years!
Relax! We're not done yet, I mean I'm not done yet making you feel bad that what you learned in highschool and even in college is somewhat inaccurate or incomplete! To complete your total confusion about these kinds of years I'll give the other kinds of years, but don't worry most of them are not that important and just for educational purpose.
Julian Year - This is the unit used for Astronomy, A Julian Year is defined as 365.25 days or 86,400 SI Seconds, and most of us only know this kind of year since we started learning things. the Julian Calendar that we use today is based on Julian Years, but what about Tropical Years?
To make things clearer, Julian Year does not follow anything, unlike the other years that counts the time span with respect to different things. However, Julian Year was intended to approximate the Tropical Year, since a tropical year was a few minutes shorter than 365.25 days, it's like rounding it off. If we use the Tropical Year for our calendars (which is the accurate measurement rather than Julian Year) we will gain about three (3) days every four centuries (Today we use the Leap Year System or one day every four years).
Draconic/Eclipse Year - The revolution of Sun with respect to the Lunar Node. One Draconic Year is equal to 346.620 Earth Days or 346 days 14 hours 52 minutes 54 seconds.
Full Moon Cycle - Complete Revolution of the Sun with respect to the perigee of Moon's Orbit. A Full Moon Cycle is 411.784 Earth Days or 411 days 18 hours 49 minutes 34 seconds.
Lunar Year - This is defined as the twelve full cycles of the Moon's Phases, Muslim's Calendars is based on Lunar Year and Ramadan is also based on this one. A Lunar Year is approximately 354.37 days.
Besselian Year - The Besselian year was named after Friedrich Bessel, a German Astronomer. A Besselian Year starts when the Sun raches 280° of ecliptic longitude. To calculate for the Besselian Year you can use this equation:
Besselian Year = 1900.0 + (Julian date in Terrestrial Time Scale/Ephemeris Time − 2415020.31352) / 365.242198781
Sothic Year - The interval between heliacal risings of a star Sirius (Current Northern Star) is called a Sothic Year. The duration of one Sothic Year is extremely close to a Julian Year (365.25 Days).
Heliacal Year - This is the interval between the heliacal risings of a star, while it is almost identical to a Sothic Year, a Heliacal Year doesn't have a specific star for its identification where a Sothic Year is based on the Sirius only.
Vague Year - Also known as annus vagus (don't laugh please), this system is mainly used in the calendars of Ancient Egypt, Armenia, Mesoamerica and Iran. This is defined as the approximation to the year equaling 365 days, typically a vague year is divided in 12 months with 30 days each plus 5 epagomenal days (days within a solar calendar that are outisde any regular month).
Gaussian Year - The Gaussian year is the sidereal year for a planet of negligible mass (relative to the Sun) and unperturbed by other planets that is governed by the Gaussian gravitational constant. Such a planet would be slightly closer to the Sun than Earth's mean distance. One Gaussian Year is 365 days, 6 hours, 9 minutes, 56 seconds or 365.256 days.
That's all..
Well I guess I ran out of source for other kinds of years, you can try including other years of your favorite game or show maybe 1 San Andreas Year or 1 Pokemon Year. Since the Full Moon Cycle is the longest year among them all you can use it in tough situation like on those projects that you need to complete at the end of the year, just say "I'm using the Full Moon Cycle Year System" then point them out to this article.
Disclaimer: I (SalbagSanting) do not take responsibility to any problem that may arise from using a different system other than the Tropical Year/Lunar Year.
Source(s):
- http://www.youtube.com/watch?feature=player_detailpage&v=53glKEPzElA
- http://en.wikipedia.org/wiki/Fixed_star
- http://en.wikipedia.org/wiki/Year
- http://en.wikipedia.org/wiki/Sidereal_year
- http://en.wikipedia.org/wiki/Tropical_year
- Christopher De Pree, Alan Axelrod (2004). The Complete Idiot's Guide to Astronomy (3rd ed.). Alpha Books.
- Calendar Description and Coordination Maya World Studies Center
- http://hpiers.obspm.fr/eop-pc/models/constants.html
- Journal of the Royal Astronomical Society of Canada
- Astronomical Almanac for the year 2011. Washington: U.S. Government Printing Office.
- http://en.wikipedia.org/wiki/Julian_year_(astronomy)
- http://en.wikipedia.org/wiki/Julian_calendar
