Gravity. Not very 9.8?

A gravity anomaly is the difference between the observed acceleration of a planet's reaction to gravity and a value predicted from a model.Certain places on the earth shows deviation from the perfect graviational equation.

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 The anomaly is the body or effect that causes the deviation from the "ideal" gravity model. There are two types of anomalies. Namely positive anomalies and negative anomalies .A location with a positive anomaly exhibits more gravity than predicted, while a negative anomaly exhibits a lower value than predicted. According to the perfect graviational  equation, Earth should basically looking like this.

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