Mars(redirected from Fourth planet)
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1. Roman Mythology The god of war.
2. The fourth planet from the sun, having a sidereal period of revolution about the sun of 687 days at a mean distance of 227.9 million kilometers (141.6 million miles) and a mean diameter of approximately 6,794 kilometers (4,222 miles).
[Middle English, from Latin Mārs.]
(Classical Myth & Legend) the Roman god of war, the father of Romulus and Remus. Greek counterpart: Ares
1. (Astronomy) Also called: the Red Planet the fourth planet from the sun, having a reddish-orange surface with numerous dark patches and two white polar caps. It has a thin atmosphere, mainly carbon dioxide, and low surface temperatures. Spacecraft encounters have revealed a history of volcanic activity and running surface water. The planet has two tiny satellites, Phobos and Deimos. Mean distance from sun: 228 million km; period of revolution around sun: 686.98 days; period of axial rotation: 24.6225 hours; diameter and mass: 53.2 and 10.7 per cent that of earth respectively
2. (Alchemy) the alchemical name for iron
1. the ancient Roman god of war and agriculture, identified with the Greek god Ares.
2. the planet fourth in order from the sun, having a diameter of 4222 mi. (6794 km), a mean distance from the sun of 141.6 million mi. (227.9 million km), a period of revolution of 686.95 days, and two moons.
[< Latin Mārs]
Astronomy. a topographical description of the planet Mars.
Astronomy. the observation and study of the planet Mars. — areologist, n. — areologic, areological, adj.
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|Noun||1.||Mars - a small reddish planet that is the 4th from the sun and is periodically visible to the naked eye; minerals rich in iron cover its surface and are responsible for its characteristic color; "Mars has two satellites"|
solar system - the sun with the celestial bodies that revolve around it in its gravitational field
|2.||Mars - (Roman mythology) Roman god of war and agriculture; father of Romulus and Remus; counterpart of Greek Ares|
Roman mythology - the mythology of the ancient Romans