New CCD photometric observations for asteroid(1028)Lydina,carried out with the 1-m and 2.4-m telescopes at Yunnan Observatory from 2011 December 19 to 2012 February 3,are presented.Using the new light curves,the rot...New CCD photometric observations for asteroid(1028)Lydina,carried out with the 1-m and 2.4-m telescopes at Yunnan Observatory from 2011 December 19 to 2012 February 3,are presented.Using the new light curves,the rotation period of 11.680±0.001 hours is derived with the Phase Dispersion Minimization(PDM) method.In addition,using the Amplitude-Aspect method,the elementary results of the pole orientation of asteroid(1028)Lydina are obtained:λp=111°+4°-4°,βp=31°+4°-5°. Meanwhile,the axial ratios of the tri-axial ellipsoid are estimated:a/b=1.77+0.10 -0.08 and b/c=1.17+0.07 -0.09 .展开更多
Lunar geodetic parameters, which play an important role in lunar exploration, can be calculated from the gravity and topography data. With the CE-1 altimetry data and LP gravity model, we calculate such geodetic param...Lunar geodetic parameters, which play an important role in lunar exploration, can be calculated from the gravity and topography data. With the CE-1 altimetry data and LP gravity model, we calculate such geodetic parameters as the principle moment of inertia, the principle inertia axes, equatorial radius, polar radius, mean radius, flattening and offset between center of mass and center of figure (DCOM-COF). According to the CE-1 altimetry data and the above geodetic parameters, a tri-axial ellipsoid (CE-1-LAM-GEO) and a tri-axial level ellipsoid (CE-1-LAM-LEVEL) are calculated individually, providing mass center and figure center offset (DCOM-COF) and parameters more reliable in direction and magnitude.展开更多
基金funded by the National Natural Science Foundation of China(Grant Nos.10933004 and 11073051)
文摘New CCD photometric observations for asteroid(1028)Lydina,carried out with the 1-m and 2.4-m telescopes at Yunnan Observatory from 2011 December 19 to 2012 February 3,are presented.Using the new light curves,the rotation period of 11.680±0.001 hours is derived with the Phase Dispersion Minimization(PDM) method.In addition,using the Amplitude-Aspect method,the elementary results of the pole orientation of asteroid(1028)Lydina are obtained:λp=111°+4°-4°,βp=31°+4°-5°. Meanwhile,the axial ratios of the tri-axial ellipsoid are estimated:a/b=1.77+0.10 -0.08 and b/c=1.17+0.07 -0.09 .
文摘Lunar geodetic parameters, which play an important role in lunar exploration, can be calculated from the gravity and topography data. With the CE-1 altimetry data and LP gravity model, we calculate such geodetic parameters as the principle moment of inertia, the principle inertia axes, equatorial radius, polar radius, mean radius, flattening and offset between center of mass and center of figure (DCOM-COF). According to the CE-1 altimetry data and the above geodetic parameters, a tri-axial ellipsoid (CE-1-LAM-GEO) and a tri-axial level ellipsoid (CE-1-LAM-LEVEL) are calculated individually, providing mass center and figure center offset (DCOM-COF) and parameters more reliable in direction and magnitude.