The JPL Planetary and Lunar Ephemerides DE440 and DE441

The planetary and lunar ephemerides called DE440 and DE441 have been generated by fittingnumerically integrated orbits to ground-based and space-based observations. Compared to theprevious general-purpose ephemerides DE430, seven years of new data have been added tocompute DE440 and DE441, with improved dynamical models and data calibration. The orbit ofJupiter has improved substantially by fitting to the Juno radio range and Very Long Baseline Array(VLBA) data of the Juno spacecraft. The orbit of Saturn has been improved by radio range andVLBA data of the Cassini spacecraft, with improved estimation of the spacecraft orbit. The orbitof Pluto has been improved from use of stellar occultation data reduced against the GAIA starcatalog. The ephemerides DE440 and DE441 are fitted to the same data set, but DE441 assumesno damping between lunar liquid core and solid mantle, which avoids a divergence when integratedbackwards in time. Therefore, DE441 is less accurate than DE440 for the current century, butcovers a much longer duration of years –13,200 to +17,191, compared to DE440 covering years1550 to 2650.

名为DE440与DE441的行星与月球星历表，系通过将数值积分轨道与地基及天基观测数据拟合生成。相较于前代通用星历表DE430，DE440与DE441的计算新增了七年的观测数据，并采用了改进的动力学模型与数据定标方法。通过拟合朱诺号（Juno）航天器的无线电测距数据以及甚长基线阵列（Very Long Baseline Array, VLBA）观测数据，木星轨道的精度得到显著提升。土星轨道的精度则通过卡西尼号航天器的无线电测距与甚长基线阵列观测数据得到优化，并实现了对该航天器轨道的更精准估计。冥王星轨道的精度提升则得益于利用了基于盖亚（GAIA）星表归算的恒星掩星观测数据。DE440与DE441均基于同一数据集进行拟合，但DE441假设月球液态核与固态幔层之间不存在阻尼作用，从而规避了时间反向积分过程中出现的数值发散问题。因此，DE441在当代百年内的精度略低于DE440，但其覆盖的时间跨度远更广：DE440的时间覆盖范围为公元1550年至2650年，而DE441可覆盖公元前13200年至公元17191年的区间。

搜集汇总

背景与挑战

背景概述

该数据集包含DE440和DE441两种行星和月球星历表，通过改进的动力学模型和新增的7年观测数据生成，显著提升了木星、土星和冥王星轨道的精度。DE441覆盖时间更长（-13,200至+17,191年），但精度较低；DE440覆盖1550至2650年，精度更高。