Run Time: 4 sec
Basic Geocentric Equatorial Astronomical Ephemeris Calculator
STILL EXPERIMENTAL
Based on the NASA/JPL HORIZONS and DE405 Ephemerides
Solar System Body Name
Sun | Moon | Mercury to Pluto
Local Calendar Date
Year Month Day
Local Clock Time
(00h to 24h)
Time Zone Offset From UTC
(Neg|Pos = West|East)
UTC
...
============================================================================== SUN Ephemeris Span From 1600 to 2025 Apparent Geocentric Equatorial Ephemeris Statistics For True Equator and Equinox of Date For 2025-Sep-17-Wed 08:17:42 LT Local Time Zone UTC+00:00:00 JD 2460935.84642572 TT Delta T +00:01:09 ------------------------------------------------------------------------------ Right Distance Visual Ascension Declination Light_Time Magn Ang_Diameter ---------------- ---------------- ------------------ ------ -------------- 11h 40m 33.587s +2° 06' 13.225" 1.005104255405 AU -26.73 0.5304284444° 11.6759964 h +2.1036737° 150,361,456 km 31.825707' 175° 08' 23.806" 93,430,277 mi 1909.54240" 175.1399460° 08m 21.552 s 0° 31' 49.542" ------------------------------------------------------------------------------ Radial Velocity of Sun Relative to Earth −Neg = Towards +Pos = Away -0.4603561 km/s = -1657.28196 km/h towards Earth = -0.2860520 mi/s = -1029.78727 mi/h towards Earth ------------------------------------------------------------------------------ ============================================================================== Calendar Date Time Julian Date JD Number --------------- ----------- ---------------- ----------- Local Date/Time 2025-Sep-17-Wed 08:17:42 LT 2460935.84562500 2460936 LT Local Time Zone +00:00:00 TZ +0.00000000 UTC 2025-Sep-17-Wed 08:17:42 UTC 2460935.84562500 2460936 UTC Delta T +00:01:09 DT +0.00080072 Astronomical TT 2025-Sep-17-Wed 08:18:51 TT 2460935.84642572 2460936 TT TAI Adjustment -00:00:32.184 -0.00037250 Atomic Time TAI 2025-Sep-17-Wed 08:18:19 TAI 2460935.84605322 2460936 TAI Horizons Delta T +69.182451s +00:01:09.182 ----> +00:01:09
=================================================================================================== For Numerical Reference: SUN 2025-Sep-17-Wed 08:17:42 LT Time Zone UTC+00:00 Working Julian Date ---> 2460935.84642572 TT Raw 11-point Lagrangian interpolation work table for the Sun Ephemeris JD_TT RA_Hrs Decl_Deg Dist_AU Rad_Vel_kps VMag Illum_% Ang_Diam_" Delta_T_Sec ========= ========== =========== =============== =========== ====== ======= ========== ============ 2460933.5 11.5357692 +03.0088914 01.005721820477 -00.4513904 -26.73 100.000 1908.37000 +0069.182472 2460934.0 11.5656507 +02.8164080 01.005591222302 -00.4531276 -26.73 100.000 1908.61800 +0069.182467 2460934.5 11.5955314 +02.6236918 01.005460107518 -00.4549670 -26.73 100.000 1908.86700 +0069.182463 2460935.0 11.6254119 +02.4307550 01.005328447851 -00.4568998 -26.73 100.000 1909.11700 +0069.182458 2460935.5 11.6552928 +02.2376101 01.005196217745 -00.4589160 -26.73 100.000 1909.36800 +0069.182454 2460936.0 11.6851747 +02.0442692 01.005063394673 -00.4610047 -26.73 100.000 1909.62000 +0069.182450 2460936.5 11.7150580 +01.8507449 01.004929959384 -00.4631542 -26.73 100.000 1909.87400 +0069.182445 2460937.0 11.7449436 +01.6570496 01.004795896083 -00.4653521 -26.73 100.000 1910.12900 +0069.182441 2460937.5 11.7748319 +01.4631956 01.004661192569 -00.4675860 -26.73 100.000 1910.38500 +0069.182437 2460938.0 11.8047236 +01.2691954 01.004525840306 -00.4698431 -26.73 100.000 1910.64200 +0069.182434 2460938.5 11.8346193 +01.0750615 01.004389834461 -00.4721105 -26.73 100.000 1910.90100 +0069.182430
====================================================================================================================== SUN - 2025 Sep 1 to Sep 30 - Month Ephemeris Table TT at 0.5-day Intervals JD_TT Calendar_Date RA_Deg Decl_Deg Geo_Dist_AU Rad_Vel_kps VMag Illum_% Ang_Diam_" Delta_T_Sec --------- --------------- ----------- ----------- --------------- ----------- ------ ------- ----------- ------------- 2460916.5 2025-Aug-29-Fri 157.7127841 +9.3368022 1.009966857550 -0.4034376 -26.72 100.000 1900.349000 +69.182702 2460917.0 2025-Aug-29-Fri 158.1678699 +9.1586596 1.009849928136 -0.4063748 -26.72 100.000 1900.569000 +69.182693 2460917.5 2025-Aug-30-Sat 158.6225891 +8.9799160 1.009732168354 -0.4091882 -26.72 100.000 1900.791000 +69.182685 2460918.0 2025-Aug-30-Sat 159.0769497 +8.8005830 1.009613614297 -0.4118754 -26.72 100.000 1901.014000 +69.182677 2460918.5 2025-Aug-31-Sun 159.5309601 +8.6206721 1.009494302733 -0.4144342 -26.72 100.000 1901.239000 +69.182669 2460919.0 2025-Aug-31-Sun 159.9846284 +8.4401949 1.009374271071 -0.4168624 -26.72 100.000 1901.465000 +69.182661 2460919.5 2025-Sep-01-Mon 160.4379629 +8.2591629 1.009253557322 -0.4191579 -26.72 100.000 1901.692000 +69.182653 2460920.0 2025-Sep-01-Mon 160.8909723 +8.0775876 1.009132200063 -0.4213189 -26.72 100.000 1901.921000 +69.182645 2460920.5 2025-Sep-02-Tue 161.3436650 +7.8954803 1.009010238378 -0.4233438 -26.72 100.000 1902.151000 +69.182638 2460921.0 2025-Sep-02-Tue 161.7960499 +7.7128523 1.008887711756 -0.4252314 -26.72 100.000 1902.382000 +69.182630 2460921.5 2025-Sep-03-Wed 162.2481358 +7.5297151 1.008764659956 -0.4269811 -26.72 100.000 1902.614000 +69.182623 2460922.0 2025-Sep-03-Wed 162.6999317 +7.3460797 1.008641122800 -0.4285930 -26.72 100.000 1902.847000 +69.182615 2460922.5 2025-Sep-04-Thu 163.1514470 +7.1619572 1.008517139899 -0.4300686 -26.72 100.000 1903.081000 +69.182608 2460923.0 2025-Sep-04-Thu 163.6026912 +6.9773586 1.008392750294 -0.4314104 -26.72 100.000 1903.315000 +69.182601 2460923.5 2025-Sep-05-Fri 164.0536741 +6.7922948 1.008267992009 -0.4326229 -26.72 100.000 1903.551000 +69.182593 2460924.0 2025-Sep-05-Fri 164.5044060 +6.6067763 1.008142901520 -0.4337124 -26.72 100.000 1903.787000 +69.182586 2460924.5 2025-Sep-06-Sat 164.9548974 +6.4208136 1.008017513134 -0.4346877 -26.72 100.000 1904.024000 +69.182579 2460925.0 2025-Sep-06-Sat 165.4051593 +6.2344172 1.007891858312 -0.4355597 -26.73 100.000 1904.261000 +69.182572 2460925.5 2025-Sep-07-Sun 165.8552033 +6.0475969 1.007765964956 -0.4363422 -26.73 100.000 1904.499000 +69.182566 2460926.0 2025-Sep-07-Sun 166.3050413 +5.8603629 1.007639856698 -0.4370510 -26.73 100.000 1904.738000 +69.182559 2460926.5 2025-Sep-08-Mon 166.7546859 +5.6727247 1.007513552227 -0.4377043 -26.73 100.000 1904.976000 +69.182552 2460927.0 2025-Sep-08-Mon 167.2041498 +5.4846921 1.007387064730 -0.4383220 -26.73 100.000 1905.216000 +69.182546 2460927.5 2025-Sep-09-Tue 167.6534462 +5.2962746 1.007260401460 -0.4389252 -26.73 100.000 1905.455000 +69.182539 2460928.0 2025-Sep-09-Tue 168.1025885 +5.1074819 1.007133563497 -0.4395355 -26.73 100.000 1905.695000 +69.182533 2460928.5 2025-Sep-10-Wed 168.5515900 +4.9183234 1.007006545722 -0.4401741 -26.73 100.000 1905.936000 +69.182527 2460929.0 2025-Sep-10-Wed 169.0004637 +4.7288090 1.006879337003 -0.4408612 -26.73 100.000 1906.176000 +69.182521 2460929.5 2025-Sep-11-Thu 169.4492226 +4.5389486 1.006751920605 -0.4416153 -26.73 100.000 1906.418000 +69.182515 2460930.0 2025-Sep-11-Thu 169.8978790 +4.3487524 1.006624274779 -0.4424527 -26.73 100.000 1906.659000 +69.182509 2460930.5 2025-Sep-12-Fri 170.3464449 +4.1582310 1.006496373496 -0.4433866 -26.73 100.000 1906.902000 +69.182504 2460931.0 2025-Sep-12-Fri 170.7949316 +3.9673950 1.006368187285 -0.4444275 -26.73 100.000 1907.145000 +69.182498 2460931.5 2025-Sep-13-Sat 171.2433499 +3.7762554 1.006239684119 -0.4455827 -26.73 100.000 1907.388000 +69.182493 2460932.0 2025-Sep-13-Sat 171.6917101 +3.5848237 1.006110830300 -0.4468565 -26.73 100.000 1907.632000 +69.182487 2460932.5 2025-Sep-14-Sun 172.1400220 +3.3931112 1.005981591320 -0.4482503 -26.73 100.000 1907.877000 +69.182482 2460933.0 2025-Sep-14-Sun 172.5882950 +3.2011298 1.005851932653 -0.4497628 -26.73 100.000 1908.123000 +69.182477 2460933.5 2025-Sep-15-Mon 173.0365384 +3.0088914 1.005721820477 -0.4513904 -26.73 100.000 1908.370000 +69.182472 2460934.0 2025-Sep-15-Mon 173.4847610 +2.8164080 1.005591222302 -0.4531276 -26.73 100.000 1908.618000 +69.182467 2460934.5 2025-Sep-16-Tue 173.9329717 +2.6236918 1.005460107518 -0.4549670 -26.73 100.000 1908.867000 +69.182463 2460935.0 2025-Sep-16-Tue 174.3811792 +2.4307550 1.005328447851 -0.4568998 -26.73 100.000 1909.117000 +69.182458 2460935.5 2025-Sep-17-Wed 174.8293923 +2.2376101 1.005196217745 -0.4589160 -26.73 100.000 1909.368000 +69.182454 2460936.0 2025-Sep-17-Wed 175.2776199 +2.0442692 1.005063394673 -0.4610047 -26.73 100.000 1909.620000 +69.182450 2460936.5 2025-Sep-18-Thu 175.7258707 +1.8507449 1.004929959384 -0.4631542 -26.73 100.000 1909.874000 +69.182445 2460937.0 2025-Sep-18-Thu 176.1741539 +1.6570496 1.004795896083 -0.4653521 -26.73 100.000 1910.129000 +69.182441 2460937.5 2025-Sep-19-Fri 176.6224786 +1.4631956 1.004661192569 -0.4675860 -26.73 100.000 1910.385000 +69.182437 2460938.0 2025-Sep-19-Fri 177.0708541 +1.2691954 1.004525840306 -0.4698431 -26.73 100.000 1910.642000 +69.182434 2460938.5 2025-Sep-20-Sat 177.5192896 +1.0750615 1.004389834461 -0.4721105 -26.73 100.000 1910.901000 +69.182430 2460939.0 2025-Sep-20-Sat 177.9677947 +0.8808062 1.004253173878 -0.4743756 -26.73 100.000 1911.161000 +69.182427 2460939.5 2025-Sep-21-Sun 178.4163790 +0.6864420 1.004115861019 -0.4766260 -26.73 100.000 1911.422000 +69.182423 2460940.0 2025-Sep-21-Sun 178.8650520 +0.4919814 1.003977901861 -0.4788498 -26.73 100.000 1911.685000 +69.182420 2460940.5 2025-Sep-22-Mon 179.3138235 +0.2974369 1.003839305753 -0.4810356 -26.73 100.000 1911.949000 +69.182417 2460941.0 2025-Sep-22-Mon 179.7627031 +0.1028208 1.003700085246 -0.4831726 -26.73 100.000 1912.214000 +69.182414 2460941.5 2025-Sep-23-Tue 180.2117005 -0.0918543 1.003560255898 -0.4852507 -26.73 100.000 1912.481000 +69.182411 2460942.0 2025-Sep-23-Tue 180.6608253 -0.2865759 1.003419836065 -0.4872607 -26.73 100.000 1912.748000 +69.182408 2460942.5 2025-Sep-24-Wed 181.1100874 -0.4813315 1.003278846678 -0.4891940 -26.74 100.000 1913.017000 +69.182405 2460943.0 2025-Sep-24-Wed 181.5594962 -0.6761086 1.003137311028 -0.4910428 -26.74 100.000 1913.287000 +69.182403 2460943.5 2025-Sep-25-Thu 182.0090615 -0.8708946 1.002995254553 -0.4928000 -26.74 100.000 1913.558000 +69.182400 2460944.0 2025-Sep-25-Thu 182.4587929 -1.0656771 1.002852704646 -0.4944592 -26.74 100.000 1913.830000 +69.182398 2460944.5 2025-Sep-26-Fri 182.9086998 -1.2604435 1.002709690475 -0.4960145 -26.74 100.000 1914.103000 +69.182395 2460945.0 2025-Sep-26-Fri 183.3587920 -1.4551811 1.002566242833 -0.4974604 -26.74 100.000 1914.377000 +69.182393 2460945.5 2025-Sep-27-Sat 183.8090788 -1.6498775 1.002422394019 -0.4987921 -26.74 100.000 1914.652000 +69.182391 2460946.0 2025-Sep-27-Sat 184.2595700 -1.8445202 1.002278177731 -0.5000047 -26.74 100.000 1914.927000 +69.182389 2460946.5 2025-Sep-28-Sun 184.7102751 -2.0390965 1.002133629003 -0.5010938 -26.74 100.000 1915.203000 +69.182387 2460947.0 2025-Sep-28-Sun 185.1612036 -2.2335940 1.001988784158 -0.5020549 -26.74 100.000 1915.480000 +69.182386 2460947.5 2025-Sep-29-Mon 185.6123651 -2.4280002 1.001843680771 -0.5028837 -26.74 100.000 1915.758000 +69.182384 2460948.0 2025-Sep-29-Mon 186.0637693 -2.6223024 1.001698357662 -0.5035759 -26.74 100.000 1916.036000 +69.182382 2460948.5 2025-Sep-30-Tue 186.5154258 -2.8164883 1.001552854874 -0.5041274 -26.74 100.000 1916.314000 +69.182381 2460949.0 2025-Sep-30-Tue 186.9673444 -3.0105453 1.001407213655 -0.5045340 -26.74 100.000 1916.593000 +69.182380 2460949.5 2025-Oct-01-Wed 187.4195348 -3.2044611 1.001261476411 -0.5047918 -26.74 100.000 1916.872000 +69.182378 2460950.0 2025-Oct-01-Wed 187.8720070 -3.3982232 1.001115686630 -0.5048973 -26.74 100.000 1917.151000 +69.182377 2460950.5 2025-Oct-02-Thu 188.3247711 -3.5918194 1.000969888742 -0.5048475 -26.74 100.000 1917.430000 +69.182376 2460951.0 2025-Oct-02-Thu 188.7778375 -3.7852373 1.000824127913 -0.5046404 -26.74 100.000 1917.709000 +69.182375 2460951.5 2025-Oct-03-Fri 189.2312166 -3.9784649 1.000678449750 -0.5042750 -26.74 100.000 1917.988000 +69.182375 2460952.0 2025-Oct-03-Fri 189.6849195 -4.1714901 1.000532899889 -0.5037521 -26.74 100.000 1918.267000 +69.182374 --------- --------------- ----------- ----------- --------------- ----------- ------ ------- ----------- ------------- JD_TT Calendar_Date RA_Deg Decl_Deg Geo_Dist_AU Rad_Vel_kps VMag Illum_% Ang_Diam_" Delta_T_Sec
EXPERIMENTAL G4 BASIC TABULAR GEOCENTRIC SOLAR SYSTEM EPHEMERIS An Astronomy Program by Jay Tanner - 2025 This simple tabular ephemeris attempts to emulate some of the computations of the NASA/JPL HORIZONS ephemeris, with a little less fuss. The lunar phases, perigees and apogees are computed from the DE405 ephemeris. Positions are for the TRUE ecliptic, equator and equinox of the date. BUG NOTE: Mercury and Venus visual magnitude glitch, where the bodies are normally not visible, still needs to be fixed. ------------------------------------------------------------------------------ SYMBOLS USED, TIME SCALES, RELATIONSHIPS AND ADJUSTMENTS G4 = Generation 4 JD = Julian Date corresponding to a given Date/Time/Zone JD Num = Julian Day Number = Calendar date serial number corresponding to JD = floor(JD + 0.5) LT = Local (Clock) Time = UT + (TZ) TZ = Local Time Zone Offset From UT (Neg|Pos = West|East) ±00:00 = UT UT = Universal Time = LT − (TZ) Where: UT means UT1 if Year < 1962 (Up to 1961) or UT means UTC if Year > 1961 (From 1962 onward) DT = Delta T = TT − UT TT = TDB = Terrestrial (Barycentric Dynamical) Time = UT + (DT) TAI = International Atomic Time = TT − 00:00:32.184 ----------------------------- DAYLIGHT SAVING / SUMMER TIME There are many places where Daylight Saving or Summer Time is not observed. Hawaii is one of them. To account for Daylight Saving or Summer Time, we simply need to reduce the standard Time Zone offset by 1 hour. For example, in New York City, when Standard Time is in effect, the standard time zone difference between universal time (UT) and local time (LT) is UT − LT = −5 hours (West of Greenwich). A negative Time Zone offset means west of Greenwich and a positive value means east of Greenwich. An offset of 00:00 is the same as UT. -5 hours means that New York City local time (LT) is 5 hours behind UT, so we have to add 5 hours to local time to obtain the correspon- ding UT for the same moment. However, when Daylight Saving Time is in effect and we set the clocks ahead by one hour, the difference between UT and LT becomes one hour less, or −4 hours instead of the standard difference of −5 hours. When Standard Time is in effect: New York City Standard Time + 5 hours = UT When Daylight Saving Time is in effect: New York City Daylight Saving Time + 4 hours = UT The above also applies to other places that observe Daylight Saving Time as well. ----------------------------------------- RADIAL VELOCITY OF BODY RELATIVE TO EARTH Every solar system body is in motion relative to Earth and is either moving towards or away from Earth at any given moment. The radius vector is the geocentric distance between the body and Earth and the radial velocity is the rate at which this distance between the body and Earth is either decreasing or increasing at any given moment along this interconnecting line. A Negative Value = Body moving towards Earth = Distance decreasing and A Positive Value = Body moving away from Earth = Distance increasing Only at the moments of perigee and apogee, does the radial velocity equate to zero momentarily before reversing trend. ---------------- LUNAR IMAGE SIZE The size of the lunar phase image varies with the lunar distance, even though the difference is subtle and not easily noticeable. The percent of average or mean size is based on a mean distance of 384400 km, with a mean angular diameter of 1779.59415" = 100.000 percent at that dist- ance. ------------------- EPHEMERIS TIME SPAN Not all of the ephemerides span the same interval. Some ephemerides span a longer or shorter time period than others, depending on the selected body. The ephemeris span will be indicated when a body name is entered. ------- COOKIES This program uses a cookie. The sole purpose of the cookie is to remember the interface settings between calls. If you navigate to another page and return later, the cookie will recall all the previous settings and restore them unless the cookie has been deleted. It is NOT a tracking cookie and in no way compromises user security. The cookie automatically expires in exactly 30 days from the moment of creation if not refreshed before then. The cookie is refreshed on each program call unless deleted between calls, in which case, the interface values will revert back to the initial default values.
Program by Jay Tanner
Revised: Thursday, January 01, 1970 at 12:00:00 AM UTC
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Basic Astronomical Ephemeris Calculator