Gravity Anomaly Map from the RSTAR "OKINA" (1/2)
Updated : 2008.09.16
Observation date :

JAXA/SELENE team announced a new finding of a gravity anomaly for both the near side and the far side of the Moon by using 4-way Doppler observation data from the RSTAR (OKINA) with the main orbiter, the KAGUYA.

Current lunar gravity field models include large uncertainties on the far side of the Moon. For instance, the figure in the middle shows the current gravity distribution model for the Apollo basin by LP165P. The color of the figure shows strength of the gravity field in blue, green, yellow, and red, in that order. Red indicates a positive gravity anomaly related to either a topographic high or a dense material in the subsurface. In contrast, blue shows that a negative gravity anomaly related to a topographic low or less dense material. The gravity anomaly shown in the figure on the left hand side is processed by new data taken by the KAGUYA. The gravity anomaly in the Apollo basin is now identified as concentric rings of yellow, blue, and thin red from the center to outside.

*Gravity anomaly: The lunar gravity field is not homogenous. Any region of the Moon with a higher than expected mass density will produce a gravity anomaly.

*LP165P: Lunar gravity model developed by Konopliv et al.. incorporating tracking data from the Lunar Prospector spacecraft into a historical data set.