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
Optional Location Label
Double-Click Within Text Area to Select ALL Text
=========================================================================== ALL MERCURY PERIGEES AND APOGEES FOR THE YEAR 2023 ================================================== Time Zone UTC+00:00 Dates refer to the modern Gregorian calendar. ======================================================================== EVENT Julian Date UTC Calendar Date Time UTC Dist. AU/mi/km ------- ----------------- --------------- ----------- ---------------- Perigee 2459952.862208557 2023-Jan-08-Sun 08:41:35 AM 0.6704379738435 62,321,103 mi 100,296,093 km Apogee 2460014.561272360 2023-Mar-11-Sat 01:28:14 AM 1.3692726471140 127,281,844 mi 204,840,272 km Perigee 2460069.085322729 2023-May-04-Thu 02:02:52 PM 0.5592976632666 51,989,966 mi 83,669,740 km Apogee 2460128.133378722 2023-Jul-02-Sun 03:12:04 PM 1.3281475375227 123,459,027 mi 198,688,044 km Perigee 2460191.133271999 2023-Sep-03-Sun 03:11:55 PM 0.6279420383468 58,370,859 mi 93,938,792 km Apogee 2460244.554976233 2023-Oct-27-Fri 01:19:10 AM 1.4352616146454 133,415,902 mi 214,712,081 km Perigee 2460301.603657290 2023-Dec-23-Sat 02:29:16 AM 0.6761813980179 62,854,988 mi 101,155,297 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:  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.  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.  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.  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.  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.  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 01:48:17 UTC - PHP v7.4.9