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May 2007 - US and Canadian scientists have used the gravity measurements from GRACE to determine that the ancient ice sheets over Canada consisted of two major ice domes rather than a single massive dome. Their analysis also indicates that post-glacial rebound is not the only source of the observed gravity changes; mantle convection also appears to play an important role.
On a GRACE satellite map, the Earth looks like a warty ball, with red bumps and deep blue holes highlighting fluctuations in the planet's gravity.