Space & PhysicsScience Plans a Mass Attack on the Moon's MysteriesAre the Moon's Craters Volcanic or Are They Meteoric "Shell-holes"?By Henry Norris Russell on February 1, 1927AdvertisementABOUT THE AUTHOR(S)Recent Articles by Henry Norris RussellGalactic Gas CloudsAnthropocentrism's DemisePlanet Companions