Only planet where one side always faces the sun. Permanent day on one side and permanent night on the other. Caused by millennia of tidal friction - same reason the same side of the moon always faces...
the earth is in the perfect place in the milky way. if it was any closer to the sun the temperate would be too hot, and if it was any further from the sun it would freeze over.
An artery that originates at the right ventricle because it is the connection of the right ventricle to the lungs, the only artery carrying CO2 rich blood.