Mars - Perigee and Apogee Calculator

Mars Perigees and Apogees Calculator
For the 899-Year Span From 1601 AD to 2499 AD
Built Around the NASA/JPL Horizons API
PHP Program by Jay Tanner

Year Time Zone UTC

Optional Location Label

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                   MARS PERIGEE AND APOGEE FOR THE YEAR 2025
               ================================================
               Time Zone UTC+00:00
               ---

               Dates refer to the modern Gregorian calendar.

========================================================================
 EVENT   Julian Date UTC   Calendar Date     Time UTC      Distance AU
------- ----------------- ---------------  -----------  ----------------
Perigee 2460688.064077461 2025-Jan-12-Sun  01:32:16 PM   0.6422767445257
Apogee  2461009.923047632 2025-Nov-30-Sun  10:09:11 AM   2.4238815619514
------- ----------------- ---------------  -----------  ----------------

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NOTES:

[1] This Mars perigee and apogee calculator spans the 899 year
    period from 1601 AD to 2499 AD.

    It was written in PHP v8.2.12 and makes internal calls to the
    NASA/JPL Horizons API.

    Julian Dates (JDate) and Calendar Dates:

    Dates up to 1582-Oct-04-Thu (2299160) refer to the Julian calendar.
    Dates from  1582-Oct-15-Fri (2299161) refer to the Gregorian calendar.

    Given JDate = General Julian Date, then the Julian Day Number
                  on the calendar is:

          JDNum = floor(JDate + 0.5)


[2] Occasionally a time-out may occur if the JPL Horizons server
    is temporarily unavailable or too busy and an error occurs.

    If such a crash or hang-up does occur, simply refresh and try
    again.  Generally, this is very rare.



[3] UT1 = Old Universal Time Scale - Solar based.
          Old previous UT time scale used for years up to 1961.

    UTC = Coordinated Universal Time Scale - Atomic based.
          Newer UT time scale used from 1962 to date.
          World times are now based on this standard.

    LT  = Local Time for the given time zone based on the
          given +/- HH:MM offset.

          Time Zone Offset Convention:
          West of Greenwich, time zone offsets are negative.
          East of Greenwich, time zone offsets are positive.



[4] Standard times are assumed. To adjust for Daylight Saving or
    Summer Time, add 1 hour to the standard times taking care to
    watch for any change of date -OR- subtract 1 hour from the
    time zone offset, which will automatically handle any date
    change.

    For example, the time zone offset for Eastern Standard Time
   (EST) is normally -5 hours. However, when Eastern Daylight Time
   (EDT) is in effect, use a time zone offset of -4 hours instead.
    The computed times will be in EDT and automatically handle any
    date changes.



[5] There is an optional location label that can be applied to the
    computed table for reference.  However, any label should match
    the indicated time zone so as to be accurate and make sense.

    For example, if using the time zone offset for India, putting
   'New York City, USA' as the location, would be rather absurd
    and an inaccurate match between location name and time zone.

    The label can consist of any printable plain-text string and
    defaults to 'Greenwich, England' at Time Zone Offset +00:00.



[6] This program implements a cookie to store and recall the year
    and other interface settings between calls. It does not track,
    monitor or perform any other activity. If you navigate away
    and come back later, the interface settings stored in the
    cookie will be recalled from your last visit.

    Each call will refresh the cookie for up to 7 days retention
    unless deleted sooner. There is no harm in deleting the cookie.
    The program will simply revert to the original default values.

Program by Jay Tanner
Revised: Friday - April 11, 2025 at 20:20:47 UTC - PHP v8.2.12
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