Mercury - Perigee and Apogee Calculator

Mercury Perigees and Apogees Calculator
For the 9799-Year Span From 200 AD to 9998 AD
Built Around the NASA/JPL Horizons API
PHP Horizons Interface by Jay Tanner

Year Time Zone UTC

Optional Location Label

Double-Click Within Text Area to Select ALL Text

===========================================================================
               ALL MERCURY PERIGEES AND APOGEES FOR THE YEAR 2025
               ==================================================
               Time Zone UTC+00:00
               

               Dates refer to the modern Gregorian calendar.

========================================================================
 EVENT   Julian Date UTC   Calendar Date     Time UTC    Dist. AU/mi/km
------- ----------------- ---------------  -----------  ----------------
Apogee  2460708.245263562 2025-Feb-01-Sat  05:53:11 PM   1.4117089786416
                                                          131,226,548 mi
                                                          211,188,657 km

Perigee 2460762.724213931 2025-Mar-28-Fri  05:22:52 AM   0.5967960404334
                                                           55,475,658 mi
                                                           89,279,417 km

Apogee  2460825.087231156 2025-May-29-Thu  02:05:37 PM   1.3218146306345
                                                          122,870,346 mi
                                                          197,740,654 km

Perigee 2460885.212679555 2025-Jul-28-Mon  05:06:16 PM   0.5876514708662
                                                           54,625,617 mi
                                                           87,911,409 km

Apogee  2460939.249613790 2025-Sep-20-Sat  05:59:27 PM   1.3986830285621
                                                          130,015,710 mi
                                                          209,240,003 km

Perigee 2460999.302844479 2025-Nov-19-Wed  07:16:06 PM   0.6771578351126
                                                           62,945,753 mi
                                                          101,301,370 km
========================================================================

NOTE:
As one can plainly see, in the case of Mercury, there are multiple
perigee/apogee events per calendar year, as many as three of each
and sometimes one extra event. For the perigee/apogee events of
the year, we could choose the lowest perigee and the largest
apogee values of the year.

Mercury is constantly moving either towards or away from Earth,
except at the perigee/apogee points, where it momentarily stands
still, then its radial distance reverses trend.

Double-Click Within Text Area to Select ALL Text


NOTES:

[1] This Mercury perigee and apogee calculator spans the 9799 year
    period from 200 AD to 9998 AD.

    It was written in PHP v7.4.9 and makes internal calls to the
    NASA/JPL Horizons API v1.1

    Julian Dates (JD) and Calendar Dates:
    JD <  2299160.5 = Refers to Old-Style Julian Calendar Dates

    JD >= 2299160.5 = Refers to Modern Gregorian Calendar Dates

    Given JD = General Julian Date, then the Julian Day Number
               on the Calendar is JD Number = floor(JD + 0.5)

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

    Technically speaking, there are no calendar dates in the range
    from 1582-Oct-05-Fri to 1582-Oct-14-Sun because those 10 dates
    were dropped from the calendar during the Julian to Gregorian
    calendar transition to bring dates of the seasons back into
    alignment with the sun and the rule for leap year was changed
    to prevent the previous calendar error from recurring.

    The date following 1582-Oct-04-Thu was 1582-Oct-15-Fri, the
    official first date on our modern Gregorian calendar system.



[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.



[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.

Download PHP 7 Source Code For This Program
Program by Jay Tanner
Revised: Friday - March 03, 2023 at 01:47:42 UTC - PHP v7.4.9