Which planet is closest to the Sun?

MERCURY is the planet closest to the Sun. ASVAB General Science includes astronomy. The planets in order from the Sun: MERCURY, VENUS, EARTH, MARS, JUPITER, SATURN, URANUS, NEPTUNE (a common mnemonic: 'My Very Educated Mother Just Served Us Noodles'). Mercury is closest (and has extreme temperatures); Venus is hottest (due to its thick atmosphere/greenhouse effect); Jupiter is largest. Knowing planetary order, especially Mercury as closest, is commonly tested.