For the seventh year in a row, an email is circulating the internet claiming that Mars will approach Earth and swell to the size of a full Moon on August 27th. It's an historic event! It's also a hoax. Mars will be 314 million km from Earth on August 27th, shining in the western sunset sky like an ordinary red star of medium brightness. To see Mars as large as the full Moon, you'll have to board a spaceship.