Interval (11.5 eclipse-years) after which another eclipse will occur
(although not the same type). This cycle is less accurate than the SAROS
Cycle or Inex.
Interval between successive conjunctions; excluding triple conjunction
intervals of Jupiter with Graffias (Beta Scorpio, 2.6 magnitude). Period
between pairs of close triple conjunctions is 70 years 5 months + 4 to 18
days. During these gaps, a series of five single conjunctions with Graffias
occur at a 12 Year - 15 days interval, with these series usually starting
in late December. Duration of each triple conjunction is 7 months + 19 to
29 days. An additional set of triple conjunctions (with close pairs) occurred
in 1900 and will reappear in 2244. Next pair of
triple conjunctions:9 Feb 2054 - 6 Oct 2054 and 16 Jan 2066 - 13 Sep
2066 .
The 5th planet from the sun revolves: 0.008 times that of Mercury, 0.052
that of Venus, 0.158 that of Mars, 2.48 times faster than Saturn, 7.08 times
Uranus, and 13.89 times Neptune.
Interval between successive conjunctions; excluding triple conjunction
intervals. Triple conjunctions last 7 months + 0 to 24 days and occurred
in 1613, 1625-6, 1702-3, 1740-1, 1792, 1843, 1919-20, 1971. Future events
include: 2009 (30' average separation), 2047-8 (42'), 2085-6 (38'), 2150
(60'), 2264-5 (13'), 2316 (52'), 2354-5 (8'), 2392 (58'), and 2443-4 (16').
For the interval between events from the year
2000 AD . For the first 30 events from 2000
AD.
Interval (14 Years 9 months) when Saturn's rings are edge-wise (invisible
from Earth). The sun spends 15 years 9 months above Saturn's northern hemisphere
and 13 years 8 months above its southern hemisphere. This imbalance is due
to Saturn's orbital eccentricity. Last passage of Earth through the plane
of Saturn's rings occurred on 21 May 1995. Just over fifty percent of these
events occur as oscillating triple passages (north-south-north or south-north-south)
through the Earth-Sun plane and last for a period of 8 months + 15 to 27
days. The next triple crossing occurs in 2038-9.
Interval when Mercury returns to approximately 6' of the same elongation
from the Sun. This situation partially explains why transits with the Sun
sometimes occur during this time span.
Interval between successive conjunctions; excluding triple conjunction
intervals. Triple conjunctions last 6 months 12 days to 7 months 9 days
and occurred in 1526-7, 1665, 1748, 1927-8, 1954-5, 1968-9, 1983. Future
triple events include: 2010-1 (35' average separation), 2037-8 (9'), 2066
(38'), 2093 (34'), 2272-3 (47'), 2355-6 (45'), and 2494 (26'). For the interval between events from the year 2000 AD.
For the first 30 events from 2000 AD.
Season's duration is 5 Years + 2 to 30 days. Next season begins 7 Jan
2005 - 7 Feb 2010 then begins again 25 Aug 2023 - 27 Aug 2028 followed by
13 Mar 2042 - 17 Mar 2047.
Season's duration is approximately 5 Years 10 months. Last season ended
20 Mar 1991. Next season begins 16 Feb 2005.
Season's duration is 3 Years 3 to 10 months. Last season began 8 Aug
1996 - 14 Feb 2000 then begins again 29 Jan 2015 - 3 Sep 2018.
Interval between Mars' closest approach to Earth. In 2003, Mars will
be the closest to Earth so far during the Christian era, and won't be closer
until 2287.
Interval after which the moon's following phase is repeated.
SAROS Cycle of Eclipses is perhaps the most familiar periodic cycle in
astronomy. The Sun and Moon will be eclipses (partially or totally) during
this time period. Simply stated, the SAROS Cycle is the result of a nearly
perfect common integral number of synodic, nodical and anomalistic months.
This period equals exactly 19 eclipse-years. There are currently 80 different
numbered SAROS Cycle series in progress. This number will range from 78
to 85 over the long term. The most common number of eclipses in a series
is 71. But the number in solar series ranges from 69 to 82, averaging 72.1;
in lunar series it ranges from 70 to 84, averaging 73.8. During the period
1900-2078, 402 solar eclipse and 409 lunar eclipses occurs (several penumbral
events approach near zero percent but are included as a statistical occurrence.
Time it takes the moon's nodes to complete one revolution (retrograde)
along the ecliptic plane (opposite to the movement of the perigee).
Interval between successive conjunctions; excluding triple conjunction
intervals. Triple conjunctions last 6 months + 7 to 25 days and occurred
in 1682-3, 1940-1, and 1980-1. Future events include: 2238-9 (44' average
separation), and 2279 (73'). Next single conjunction occurs on 28 May, 2000
(69'). For the interval between events from
the year 2000 AD. For the first 30 events from
2000 AD.
Metonic Cycle (235 Synodic months): Moon repeats its phase on nearly
the same day of the year but is generally two hours longer than 19 calendar
years (leap-years account for the additional day(s)). This accounts for
a total lunar eclipse that is followed and proceed by a partial eclipses
+/- 19 years within a few hours of that referenced eclipse (20 eclipse-years).
For example: Total eclipse (1.38 magnitude) on 18 Nov 2040 at 19:05 U.T.
will be partial (0.19 magnitude) on 19 Nov 2059 at 13:00 U.T. and partial
(0.95) on 19 Nov 2021 at 00:00 U.T.. If a total eclipse is followed or preceded
by another, then the eclipses bracketing these two events will be either
one or two penumbral or one penumbral and or one partial eclipse.
Interval when the moon's preceding phase is repeated.
Mercury returns to approximately 0.1 degrees declination and +1 minute
R.A. position in the sky (exactly 85 synodic cycles equals exactly 27 years).
Interval between successive conjunctions; excluding triple conjunction
intervals. For the brightest and nearest Saturn-star
conjunctions.
A period after which another (although not the same type) eclipse of
the Sun or Moon will occur (known as an Inex). Succeeding eclipses shift
0.0411 degrees east because the different between 358 synodic and 30.5 eclipse-years
is 0.04 days. Each Inex series last for more than 23,000 years.
The 6th planet from the sun revolves: 0.0028 times that of Mercury, 0.0208
that of Venus, 0.0223 that of Mars, 0.4032 that of Jupiter, 2.85 faster
than Uranus, and 5.59 times Neptune.
As a result of the moon's axis inclined of 6 degs 5 min, elliptical orbit,
and Earth's and moon's rotations, 59% of the moon's surface is eventually
visible during this time period.
Series interval between Venus-Mars repeated conjunctions. In 32 years,
15 to 17 different conjunctions occur with nearly each one repeating in
turn. Some series last >1200 years (up to 40 events). Others are considerably
shorter. At the beginning and end of these series, the interval can be one
week longer than 32 years. The reason why this happens is because for nearly
every 20 times Venus returns to its similar position in the sky, Mars completes
almost 15 returns. If these cycles were exactly whole numbers, the repeated
conjunctions would last much longer.
Interval when Mercury returns to approximately 4' of the same elongation
from the Sun.
Interval between successive conjunctions; excluding triple conjunction
intervals. Triple conjunctions last 8 months +2 to 10 days and occurred
in 1523-4, 1629-30, 1846, 1952-3, 1989. Future triple events include: 2132
(27' average separation), 2348-9 (46'), and 2454-5 (37'). Next single conjunction
will occur on 20 Feb 2026 (50'). For the interval
between events from the year 2000 AD. For the first
30 events from 2000 AD.
Interval between successive conjunctions; excluding triple conjunction
intervals. Triple conjunctions last 7 months + 18 to 39 days and occurred
in 1580, 1623-4, 1761-2, 1897, 1988. Future triple events include: 2079
(16' average separation), 2122-3 (22'), and 2260-1 (81'). Next single conjunction
will occur on 28 Jun 2032 (71'). Close conjunctions (<=10') occurred
in 4592 BC, 4045, 4003, 2957, 2367, 1235, 646 BC, 991 A.D., 1034, 1580,
and 1623. Next close pairings occur in 2079, 2669, 2712, and 4391. For the
interval between events from the year 2000
AD. For the first 30 events from 2000 AD.
Mercury returns to approximately 1' of the same elongation from the Sun.
In approximately 47 years, Mercury, Mars, and Jupiter complete 148, 22,
and 43 synodic cycles; respectively. Generally, a parallel series of near
trio conjunctions are occurring +/- 2 years and 10 weeks.
Mars returns to approximately 0.1 degrees declination and +1 minute R.A.
position in the sky (exactly 22 synodic cycles equals 47.008 years).
An eclipse repetition cycle equal to three SAROS Cycle cycles (known
as an Exeligmos). A solar eclipse returns to almost the same longitude,
but occurs about 600 miles north or south of its predecessor.
Interval of 61 eclipse years. A total eclipse of the sun is followed
by an annular eclipse occurring 36 degrees further east.
Saturn returns to approximately 0.3 degrees declination and +9 minute
R.A. position in the sky (exactly 57 synodic cycles equals exactly 59 years).
The moon is displaced 0.9 degrees with respect to its node (12% of the
metonic cycle displacement). As a result, similar types of eclipses will
return many more times for this eclipse cycle.
More accurate interval for predicting the best oppositions of Mars.i.Mars:Closest to Earth;. At each return, Mars is within 0.9 degrees declination and 11' R.A. of its previous appearance.
Jupiter returns to approximately 0.1 degrees declination and +1 minute
R.A. position in the sky (exactly 76 synodic cycles equals exactly 83 years).
Interval between triple conjunctions of Uranus with the stars Regulus
(1.3 magnitude. Duration of triple conjunctions is 9 months + 14 to 19 days.
The next events with Regulus occurs 16 Oct 2045 - 31 Jul 2046. For the brightest and nearest Uranus-star conjunctions.
The 7th planet from the sun revolves nearly: 350 times slower than Mercury,
137 times slower than Venus, 45 times slower than Mars, 7 times slower than
Saturn, and 1.96 times faster than Neptune. In the years 2124 2208 and 2396
and 2480; 84 years + 2 to 3 days apart, Uranus will occult the same stars
(7.1 and 4.5 magnitude), respectively.
This interval is useful for determining eclipses from the distant present.
Interval between close (<20') triple and quintuple conjunctions of Neptune with the stars Regulus (1.3 magnitude). Duration of triple conjunctions is 10 months +/- 4 days. Quintuple conjunctions of Regulus occurred in 115-7, 609-11, 1268-70, and 1927 (interval of 492 or 657 years) with a duration of 19 months 11 to 15 days. The next event with Regulus occurs 8 Oct 2092 - 9 Aug 2093. A similar pattern exists for the star Mu Gemini (2.8 magnitude) although separation ranges from 10 to 18 arc minutes. For the brightest and nearest Neptune-star conjunctions.
The 8th planet from the sun revolves nearly: 684 times slower than Mercury,
268 times slower than Venus, 88 times slower than Mars, 14 times slower
than Saturn, and 2 times slower than Uranus.
Interval between successive conjunctions; excluding triple conjunction intervals. Triple conjunctions last 9 months +/- 5 days and occurred in 1650, 1821, 1993. Future event includes: 2336-7. The separation has been decreasing with each conjunction since 1479 (91' mean separation) to 2336-7 (28'). Next conjunction will begin on 17 Jan 2165 (47'). Close triple conjunctions (<=10') occurred in 3835-4 BC and 1607 BC (281-2 and 452-3 A.D. just missing this criteria). Next close triples occur in 2508-9, 4567-8, 6794-5, and 8682-3.
Mercury's transit cycles repeat.
Mars returns to within 0.75 degrees declination and 15' R.A at opposition.
Distance from Earth is within 0.003 AU at each successive event.
Although this astronomical phenomena should be considered as a non-periodical
event (in Chapter 2), the secular (very long term) worldwide average would
be very close to the 410 years as seen--> Total Solar Eclipses (1-1000AD) or Worldwide. However, if a specific locale for witnessing
solar totality is examined, the following occurs. During this current epoch
when the Northern Hemisphere is further from the Sun (near the Summer Solstice),
the average frequency for totality is closer to one in 320 years (at 45
north latitude) while the Southern Hemisphere, at latitude 45 south, is
nearly 640 years. On average, the polar regions will see more totality although
of shorter duration and lower in the sky. Sometimes a site can have two
consecutive solar eclipses with totality (Halifax, Nova Scotia - 7 March
1970 10 July 1972). During the period 1878-1979, the U.S. had 13 total eclipses;
between 1842-1905, Spain had five; between 1901-1934, the East Indies had
four; and between 594-1999, Great Britain had 22 events (five in Edinburgh).
During the period 1-4000 A.D., the Front Range of the Rocky Mountains in
Colorado has a totality frequency of approximately 178 years; most in the
Continental US. The region with the fewest totality events is near Jacksonville,
FL where the frequency average about one event every 400 years. For accessible
land areas (worldwide), there is a rough average of one minute of totality
per year (one in three total eclipses are favorably placed in tropical and
mid-latitudes). On the opposite end, the longest duration without even experiencing
a partial solar eclipse is 18.5 years (e.g. 15N 90W (453-472 A.D.).
Interval used for long term eclipse predictions.
Interval between the start of the eclipsed moon occultation of Regulus.
During this period, the full moon is displaced, relative to the stars, only
0.09 degrees (about 5 degrees with respect to its node). Each eclipse-occultation
series lasts approximately 233 years (panorama shows a 19 and 65 year interval
separation). The start of the next series will occur in 2510. The last one
ended in 1943.
A Platonic Year. Period required by Earth to complete a precession of the equinoxes. Polaris will approach the true celestial north pole in 2102 (27' 31" distance), Vega in about 13,000 years.
