132 lines
6.7 KiB
Plaintext
132 lines
6.7 KiB
Plaintext
API VERSION: 1.2
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API SOURCE: NASA/JPL Horizons API
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Revised: April 12, 2021 Earth 399
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GEOPHYSICAL PROPERTIES (revised May 9, 2022):
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Vol. Mean Radius (km) = 6371.01+-0.02 Mass x10^24 (kg)= 5.97219+-0.0006
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Equ. radius, km = 6378.137 Mass layers:
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Polar axis, km = 6356.752 Atmos = 5.1 x 10^18 kg
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Flattening = 1/298.257223563 oceans = 1.4 x 10^21 kg
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Density, g/cm^3 = 5.51 crust = 2.6 x 10^22 kg
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J2 (IERS 2010) = 0.00108262545 mantle = 4.043 x 10^24 kg
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g_p, m/s^2 (polar) = 9.8321863685 outer core = 1.835 x 10^24 kg
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g_e, m/s^2 (equatorial) = 9.7803267715 inner core = 9.675 x 10^22 kg
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g_o, m/s^2 = 9.82022 Fluid core rad = 3480 km
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GM, km^3/s^2 = 398600.435436 Inner core rad = 1215 km
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GM 1-sigma, km^3/s^2 = 0.0014 Escape velocity = 11.186 km/s
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Rot. Rate (rad/s) = 0.00007292115 Surface area:
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Mean sidereal day, hr = 23.9344695944 land = 1.48 x 10^8 km
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Mean solar day 2000.0, s = 86400.002 sea = 3.62 x 10^8 km
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Mean solar day 1820.0, s = 86400.0 Love no., k2 = 0.299
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Moment of inertia = 0.3308 Atm. pressure = 1.0 bar
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Mean surface temp (Ts), K= 287.6 Volume, km^3 = 1.08321 x 10^12
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Mean effect. temp (Te), K= 255 Magnetic moment = 0.61 gauss Rp^3
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Geometric albedo = 0.367 Vis. mag. V(1,0)= -3.86
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Solar Constant (W/m^2) = 1367.6 (mean), 1414 (perihelion), 1322 (aphelion)
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HELIOCENTRIC ORBIT CHARACTERISTICS:
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Obliquity to orbit, deg = 23.4392911 Sidereal orb period = 1.0000174 y
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Orbital speed, km/s = 29.79 Sidereal orb period = 365.25636 d
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Mean daily motion, deg/d = 0.9856474 Hill's sphere radius = 234.9
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*******************************************************************************
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Ephemeris / API_USER Thu Aug 14 15:51:50 2025 Pasadena, USA / Horizons
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*******************************************************************************
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Target body name: Earth (399) {source: DE441}
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Center body name: Sun (10) {source: DE441}
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Center-site name: BODY CENTER
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Start time : A.D. 2025-Jan-01 00:00:00.0000 TDB
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Stop time : A.D. 2025-Jan-01 00:01:00.0000 TDB
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Step-size : 1 minutes
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*******************************************************************************
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Center geodetic : 0.0, 0.0, 0.0 {E-lon(deg),Lat(deg),Alt(km)}
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Center cylindric: 0.0, 0.0, 0.0 {E-lon(deg),Dxy(km),Dz(km)}
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Center radii : 695700.0, 695700.0, 695700.0 km {Equator_a, b, pole_c}
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Output units : AU-D
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Calendar mode : Mixed Julian/Gregorian
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Output type : GEOMETRIC cartesian states
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Output format : 2 (position and velocity)
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Reference frame : Ecliptic of J2000.0
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*******************************************************************************
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JDTDB
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X Y Z
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VX VY VZ
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$$SOE
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2460676.500000000 = A.D. 2025-Jan-01 00:00:00.0000 TDB
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X =-1.786834409731047E-01 Y = 9.669827953774551E-01 Z =-5.109423915082682E-05
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VX=-1.720473858166942E-02 VY=-3.193533189307208E-03 VZ= 5.457174067040888E-09
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2460676.500694444 = A.D. 2025-Jan-01 00:01:00.0000 TDB
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X =-1.786953886946605E-01 Y = 9.669805775731443E-01 Z =-5.109423538992340E-05
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VX=-1.720469949887746E-02 VY=-3.193743226004856E-03 VZ= 5.374519991317428E-09
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$$EOE
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*******************************************************************************
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TIME
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Barycentric Dynamical Time ("TDB" or T_eph) output was requested. This
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continuous coordinate time is equivalent to the relativistic proper time
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of a clock at rest in a reference frame co-moving with the solar system
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barycenter but outside the system's gravity well. It is the independent
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variable in the solar system relativistic equations of motion.
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TDB runs at a uniform rate of one SI second per second and is independent
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of irregularities in Earth's rotation.
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CALENDAR SYSTEM
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Mixed calendar mode was active such that calendar dates after AD 1582-Oct-15
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(if any) are in the modern Gregorian system. Dates prior to 1582-Oct-5 (if any)
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are in the Julian calendar system, which is automatically extended for dates
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prior to its adoption on 45-Jan-1 BC. The Julian calendar is useful for
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matching historical dates. The Gregorian calendar more accurately corresponds
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to the Earth's orbital motion and seasons. A "Gregorian-only" calendar mode is
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available if such physical events are the primary interest.
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REFERENCE FRAME AND COORDINATES
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Ecliptic at the standard reference epoch
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Reference epoch: J2000.0
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X-Y plane: adopted Earth orbital plane at the reference epoch
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Note: IAU76 obliquity of 84381.448 arcseconds wrt ICRF X-Y plane
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X-axis : ICRF
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Z-axis : perpendicular to the X-Y plane in the directional (+ or -) sense
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of Earth's north pole at the reference epoch.
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Symbol meaning [1 au= 149597870.700 km, 1 day= 86400.0 s]:
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JDTDB Julian Day Number, Barycentric Dynamical Time
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X X-component of position vector (au)
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Y Y-component of position vector (au)
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Z Z-component of position vector (au)
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VX X-component of velocity vector (au/day)
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VY Y-component of velocity vector (au/day)
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VZ Z-component of velocity vector (au/day)
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ABERRATIONS AND CORRECTIONS
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Geometric state vectors have NO corrections or aberrations applied.
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Computations by ...
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Solar System Dynamics Group, Horizons On-Line Ephemeris System
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4800 Oak Grove Drive, Jet Propulsion Laboratory
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Pasadena, CA 91109 USA
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General site: https://ssd.jpl.nasa.gov/
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Mailing list: https://ssd.jpl.nasa.gov/email_list.html
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System news : https://ssd.jpl.nasa.gov/horizons/news.html
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User Guide : https://ssd.jpl.nasa.gov/horizons/manual.html
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Connect : browser https://ssd.jpl.nasa.gov/horizons/app.html#/x
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API https://ssd-api.jpl.nasa.gov/doc/horizons.html
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command-line telnet ssd.jpl.nasa.gov 6775
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e-mail/batch https://ssd.jpl.nasa.gov/ftp/ssd/horizons_batch.txt
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scripts https://ssd.jpl.nasa.gov/ftp/ssd/SCRIPTS
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Author : Jon.D.Giorgini@jpl.nasa.gov
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*******************************************************************************
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