Fall Astronomy Day 2024 is on Friday, October 4, 2024: how many days in the year?
Friday, October 4, 2024 is Fall Astronomy Day 2024. AANC - Astronomy Day Astronomy Day
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A calendar year is the time between two dates with the same name in a calendar.
Solar calendars usually aim to predict the seasons, but because the length of individual seasonal years varies significantly, they instead use an astronomical year as a surrogate. For example, the ancient Egyptians used the heliacal rising of Sirius to predict the flooding of the Nile.
The Gregorian calendar aims to keep the vernal equinox on or close to March 21; hence it follows the vernal equinox year. The average length of its year is 365.2424 days.
Among solar calendars in wide use today, the Persian calendar is one of the most precise. Rather than being based on numerical rules, the Persian year begins on the day (for the time zone of Tehran) on which the vernal equinox actually falls, as determined by precise astronomical computations.
No astronomical year has an integer number of days or lunar months, so any calendar that follows an astronomical year must have a system of intercalation such as leap years.
In the Julian calendar, the average length of a year was 365.25 days. This is still used as a convenient time unit in astronomy.
The sidereal year is the time for the Earth to complete one revolution of its orbit, as measured in a fixed frame of reference (such as the fixed stars, Latin sidus). Its duration in SI days of 86,400 SI seconds each is on average:
365.256 363 051 days (365 d 6 h 9 min 9 s) (at the epoch J2000.0 = 2000 January 1 12:00:00 TT)
A tropical year is the time for the Earth to complete one revolution with respect to the framework provided by the intersection of the ecliptic (the plane of the orbit of the Earth) and the plane of the equator (the plane perpendicular to the rotation axis of the Earth). Because of the precession of the equinoxes, this framework moves slowly westward along the ecliptic with respect to the fixed stars (with a period of about 26,000 tropical years); as a consequence, the Earth completes this year before it completes a full orbit as measured in a fixed reference frame. Therefore a tropical year is shorter than the sidereal year. The exact length of a tropical year depends on the chosen starting point: for example the vernal equinox year is the time between successive vernal equinoxes. The mean tropical year (averaged over all ecliptic points) is:
365.242 189 67 days (365 d 5 h 48 min 45 s) (at the epoch J2000.0).
The anomalistic year is the time for the Earth to complete one revolution with respect to its apsides. The orbit of the Earth is elliptical; the extreme points, called apsides, are the perihelion, where the Earth is closest to the Sun (January 2 in 2000), and the aphelion, where the Earth is farthest from the Sun (July 2 in 2000).
Because of gravitational disturbances by the other planets, the shape and orientation of the orbit are not fixed, and the apsides slowly move with respect to a fixed frame of reference. Therefore the anomalistic year is slightly longer than the sidereal year. It takes about 112,000 years for the ellipse to revolve once relative to the fixed stars. The anomalistic year is also longer than the tropical year (which calendars attempt to track) and so the date of the perihelion gradually advances every year. It takes about 21,000 years for the ellipse to revolve once relative to the vernal equinox, thus for the date of perihelion to return to the same place (given a calendar that tracks the seasons perfectly).
The average duration of the anomalistic year is:
365.259 635 864 days (365 d 6 h 13 min 52 s) (at the epoch J2000.0).
The draconitic year, eclipse year or ecliptic year is the time for the Sun (as seen from the Earth) to complete one revolution with respect to the same lunar node (a point where the Moon's orbit intersects the ecliptic). This period is associated with eclipses: these occur only when both the Sun and the Moon are near these nodes; so eclipses occur within about a month of every half eclipse year. Hence there are two eclipse seasons every eclipse year. The average duration of the eclipse year is:
346.620 075 883 days (346 d 14 h 52 min 54 s) (at the epoch J2000.0).
This term is sometimes also used to designate the time it takes for a complete revolution of the Moon's ascending node around the ecliptic: 18.612 815 932 years (6798.331 019 days; at the epoch J2000.0).
The full moon cycle or fumocy is the time for the Sun (as seen from the Earth) to complete one revolution with respect to the perigee of the Moon's orbit. This period is associated with the apparent size of the full moon, and also with the varying duration of the synodic month. The duration of one full moon cycle is:
411.784 430 29 days (411 d 18 h 49 min 34 s) (at the epoch J2000.0).
A heliacal year is the interval between the heliacal risings of a star. It equals the sidereal year except for a very minor difference due to the proper motion of the star and the precession of the equinoxes. (To visualise the latter: the constellation Crux which rose and set as seen from the Mediterranean in ancient Greek times, is never above the horizon in current times.)
The Sothic year is the interval between heliacal risings of the star Sirius. Its duration is very close to the mean Julian year of 365.25 days.
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. Its length is:
365.256 898 3 days (365 d 6 h 9 min 56 s).
The Besselian year is a tropical year that starts when the fictitious mean Sun reaches an ecliptic longitude of 280°. This is currently on or close to 1 January. It is named after the 19th century German astronomer and mathematician Friedrich Bessel. An approximate formula to compute the current time in Besselian years from the Julian day is:
B = 2,000 + (JD - 2,451,544.53) /365.242189
The Great year, Platonic year, or Equinoctial cycle corresponds to a complete revolution of the equinoxes around the ecliptic. Its length is about 25,700 years, and cannot be determined precisely as the precession speed is variable.
The Galactic year is the time it takes Earth's solar system to revolve once around the galactic center. It comprises roughly 226 million Earth years.
2012 astronomy? wouldn't we know already?
Ugh... we were all warned 2 millennia ago...
Winter solstice 2012 is just the revealing of the 'antichrist' or the 'man of perdition' at the mid-point of what Christians call the 7 year Tribulation (just subtract 1260 days to get the start and add 1260 days to get the end). Satanists and many pagan cultures from every corner of the world all throughout history have celebrated this like the Sumerians, Babylonians, Cherokee, Hopi, Chinese I-Ching (confirmed by Terence McKenna), Mayans (Pacal Votan; Chilam Balam of Tizimin, Mani, Chumayel; Jaguar Prophet), Egyptians, Celts, etc. This evil event is called "the abomination that causes desolation" that will be set up in the Jewish Temple's Holy of Holies when the antichrist is imbued with the spirit of satan himself. When will Jesus come? Only God Himself knows exactly, but very soon in "the twinkling of an eye" and like "a thief in the night". If you believe or not, that is up to you; either way it still comes.
Things to look for to PROVE it to yourself soon:
>Fall of America as an economic power and other ways. The buying up and consolidation of powerful banks and corporations by the government in a pretend "bail out" power grab to kill the U.S. dollar and bring in a one world currency.
Crash of other American banks and the nation's financial underpinning: Operation Sitting Duck
>The Big One: Revelation 18. America goes down on the list of fabled societies nobody believes in any more like Atlantis, Mu, Lemuria, Hyperborea, etc..
>Martial law. (Google some of Bush's executive orders concerning it- Nightmarish!)
>The fallen 'alien' agenda: Implementation of Project Bluebeam (be ready to hear more and more 'alien talk' & watch your local skies for the show!)
Just in time for 2012! After decades of conditioning, billions will fall for it. Will you?
(2 Thessalonians 2:9-12)
WHY DID WE EVEN DIG THEM UP?
>Revelation 13:16-18 Trying to make people first accept the REAL ID card (to get you in the system) and then right after forcibly implanting people with these RFID microchips- the coming 'answer' to the world economic crisis:
>The start of the North American Union and true globalization..
>Push to attack Iran which will start WW3-the atomic war to end all wars. (If you think China, Russia, and the Muslim world would just sit back, you are a mistaken fool!). Escalation of the Georgian/Russian; Israeli/Palestinian; & Indian/Pakistani conflicts.
>Final push to one world government: The New World Order- The 4th Reich! (The brutal final empire foreseen by the prophet Daniel and John the Revelator)
>Rise of a miraculous and awe inspiring world leader later to turn world dictator.
>Push to one world religion where there are "many ways to God".
>Toleration of everything but Jews and Christians.
>Temporary and unheard of "peace in the middle east".
>Revelation13:10
>More world wide food shortages and famines.
>More earth quakes. More fires. Strange and severe weather.
>Major spiritual awakenings.
>Rise of Islamic fanaticism.
>Rise in wickedness and corruption.
>Take a few minutes to listen to what this young child uncovered:
Christians look forward to this as it means they will soon join their Saviour & Redeemer in the Millennial Kingdom of the next Age and their Heavenly Father later as "Children of Light". If you try to equate 2012 with Y2K or some other date that cried wolf, then you will be making the worst mistake of your lifetime. Research all these things FOR YOURSELF!
physics/astronomy help? (latitude and longitude)?
A dropped object starts its fall quite slowly, but then steadily increases its velocity--accelerates--as time goes on. Galileo showed that (ignoring air resistance) heavy and light objects accelerated at the same constant rate as they fell, that is, their speed (or "velocity") increased at a constant rate. The velocity of a ball dropped from a high place increases each second by a constant amount, usually denoted by the small letter g (for gravity). In modern units (using the convention of algebra, that symbols or numbers standing next to each other are understood to be multiplied) its velocity is
at the start -- 0 (zero)
after 1 second-- g meters/second
after 2 seconds-- 2g meters/second
after 3 seconds-- 3g meters/second
10] The mean distance of Neptune from the Sun is 30.07 AU (=astronomical unit, means Earth-Sun distance), that of Pluto 39.4 AU. Are these two numbers connected? (Hint: Derive the ratio of the orbital periods!)
You can also find additon information at the websites ive linked.
