Lunar Perigee and Apogee Calculator 2004

http://www.fourmilab.ch/earthview/pacalc.html
 

Distance du centre de la Terre (R = 6378 Km)

             Perigée                                                        Apogée
---------------------------------               ---------------------------------

                                    Jan  3 20:20 405706 km    F-3d19h

Jan 19 19:26 362767 km    N-2d 1h           Jan 31 14:01 404806 km    F-5d18h
Feb 16  7:35 368319 km    N-4d 1h           Feb 28 10:46 404257 km    F-7d12h
Mar 12  3:38 369509 km    F+5d 4h           Mar 27  7:03 404519 km    N+6d 8h
Apr  8  2:29 364547 km    F+2d15h           Apr 24  0:27 405402 km    N+4d11h
May  6  4:30 359811 km    F+1d 7h           May 21 12:03 406261 km -  N+2d 7h
Jun  3 13:11 357248 km ++ F+   8h           Jun 17 16:03 406574 km -- N-   4h
Jul  1 23:01 357449 km +  F-  12h           Jul 14 21:09 406191 km -  N-2d14h
Jul 30  6:27 360325 km    F-1d11h           Aug 11  9:35 405290 km    N-4d15h
Aug 27  5:38 365105 km    F-2d20h       Sep  8  2:43 404462 km    N-6d11h
Sep 22 21:13 369599 km    F-5d15h       Oct  5 22:11 404326 km    F+7d 9h
Oct 18  0:04 367757 km    N+3d21h       Nov  2 18:10 404998 km    F+5d15h
Nov 14 13:55 362312 km    N+1d23h       Nov 30 11:26 405951 km    F+3d15h
Dec 12 21:31 357985 km    N+  20h       Dec 27 19:16 406487 km +  F+1d 4h
 

      Nouvelle Lune               Pleine Lune
   2003 Dec 23  9:45        2004 Jan  7 15:43
   2004 Jan 21 21:08        2004 Feb  6  8:50
   2004 Feb 20  9:21        2004 Mar  6 23:17
   2004 Mar 20 22:45        2004 Apr  5 11:05
   2004 Apr 19 13:24        2004 May  4 20:36
   2004 May 19  4:55        2004 Jun  3  4:21
   2004 Jun 17 20:29        2004 Jul  2 11:10
   2004 Jul 17 11:25        2004 Jul 31 18:06
   2004 Aug 16  1:24        2004 Aug 30  2:23
   2004 Sep 14 14:29        2004 Sep 28 13:09
   2004 Oct 14  2:48        2004 Oct 28  3:08
   2004 Nov 12 14:27        2004 Nov 26 20:08
   2004 Dec 12  1:29        2004 Dec 26 15:07
   2005 Jan 10 12:04
 

To display the date, time, and distance of lunar perigees and apogees for a given year, enter the year in the
box below and press "Calculate". Depending on the speed of your computer, it may take a while for the
results to appear in the text boxes. This page requires your browser to support JavaScript, and that
JavaScript be enabled; all computation is done on your own computer so you can, if you wish, save this
page in a file and use it even when not connected to the Internet.

               Year:

                          Perigees and Apogees
 
 

                           New and Full Moons
 
 

The Perigee and Apogee Table


 

All dates and times are Universal time (UTC); to convert to local time add or subtract the difference
between your time zone and UTC, remembering to include any additional offset due to summer time for
dates when it is in effect. For each perigee and apogee the distance in kilometres between the centres of
the Earth and Moon is given. Perigee and apogee distances are usually accurate to within a few kilometres
compared to values calculated with the definitive ELP 2000-82 theory of the lunar orbit; the maximum
error over the years 1977 through 2022 is 12 km in perigee distance and 6 km at apogee.

The closest perigee and most distant apogee of the year are marked with "++" if closer in time to full
Moon or "--" if closer to new Moon. Other close-to-maximum apogees and perigees are flagged with a
single character, again indicating the nearer phase. Following the flags is the interval between the moment
of perigee or apogee and the closest new or full phase; extrema cluster on the shorter intervals, with a
smaller bias toward months surrounding the Earth's perihelion in early January. "F" indicates the perigee or
apogee is closer to full Moon, and "N" that new Moon is closer. The sign indicates whether the perigee or
apogee is before ("-") or after ("+") the indicated phase, followed by the interval in days and hours. Scan
for plus signs to find "photo opportunities" where the Moon is full close to apogee and perigee.

The Moon Phase Table

This table gives the time of all new and full Moons in the indicated year, as well as the last phase of the
preceding year and the first phase of the next year.

References

Meeus, Jean. Astronomical Algorithms . Richmond: Willmann-Bell, 1998.
ISBN 0-943396-63-8.
    The essential reference for computational positional astronomy. The
    calculation of perigee and apogee time and distance is performed using the
    algorithm given in Chapter 48.

Meeus, Jean. Astronomical Formulæ for Calculators, Fourth Edition . Richmond: Willmann-Bell, 1988.
ISBN 0-943396-22-0.
    This book, largely superseded by the more precise algorithms given in Astronomical Algorithms,
    remains valuable when program size and speed are more important than extreme precision. The date
    and time of the phases of the Moon are calculated using the method given in Chapter 32, and are
    accurate within 2 minutes, more than adequate for our purposes here. The more elaborate method in
    Chapter 47 of Astronomical Algorithms reduces the maximum error to 17.4 seconds (and mean
    error to less than 4 seconds), but would substantially increase the size and download time for this
    page, and the calculation time for each update.

Chapront-Touzé, Michelle and Jean Chapront. Lunar Tables and Programs from 4000 B.C. to A.D. 8000
. Richmond: Willmann-Bell, 1991. ISBN 0-943396-33-6.
    If you need more precise calculation of the Moon's position than given in the references above,
    you're probably going to end up here. This book presents the ELP 2000-85 theory which, while less
    accurate than ELP 2000-82, has been tested for stability over a much longer time span. ELP
    2000-85 generates predictions of lunar longitude accurate to 0.0004 degrees for the years 1900
    through 2100, and 0.0054 degrees for the period 1500 through 2500.

Chapront-Touzé, Michelle and Jean Chapront. Lunar solution ELP 2000-82B.
    This is the most precise semi-analytical theory of the Moon's motion for observations near the
    present epoch. Machine-readable files for all of the tables and a sample FORTRAN program which
    uses them to compute lunar ephemerides may be obtained from the Astronomical Data Center at the
    NASA Goddard Space Flight Center by FTP across the Internet, or on CD-ROM, along with a wide
    variety of other astronomical catalogues and tables. This material is intended for experts in
    positional astronomy and computation. If you can't figure it out, don't ask me for help.

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by John Walker
May 5, 1997
                      This document is in the public domain.