sciencehabit writes "A new analysis of isotopes found in lunar minerals challenges the prevailing view of how Earth's nearest neighbor formed. Geochemists looked at titanium isotopes in 24 separate samples of lunar rock and soil, and found that the moon's proportion was effectively the same as Earth's and different from elsewhere in the solar system. This contradicts the so-called Giant Impact Hypothesis, which posits that Earth collided with a hypothetical, Mars-sized planet called Theia early in its existence, and the resulting smash-up produced a disc of magma orbiting our planet that later coalesced to form the moon."
The rule on staying alive as a forecaster is to give 'em a number or
give 'em a date, but never give 'em both at once.
-- Jane Bryant Quinn