Mars is the fourth planet from the Sun. Mars has been discovered and observed since ancient times. It is commonly referred to as the "Red Planet" because of its reddish hue that is given by the iron oxide on its surface.
Mars is the most similar planet to Earth, because it has water glaciers on its poles and orbits in the outer edge of its place in the outer habitable zone. Mars has two asteroid-like natural satellites: Phobos and Deimos. The former being larger.
Atmosphere
Mars' atmosphere is very thin, about only a hundredth of Earth's atmosphere density.
Composition
Mars's atmosphere is made up of 95% carbon dioxide, 3% nitrogen, 2% and argon, and other traces of gases and water. The atmospheric pressure of Mars equals 40 kilometers in altitude on Earth.
Geographical Features
Main article: Areology of Mars
Mars is home to the tallest mountain range in the Solar System, called Olympus Mons. It is three times taller than that of Mount Everest. It is also a volcano, but does not erupt anymore and is now a type of extinct volcano referred to as dormant volcano. Its last eruption took place about 15 to 8 million years ago.
Valles Marineris
Another geographical feature is the Valles Marineris, which means "Mariner Valleys". It is 700 km in width, leaving the Grand Canyon in the dust only reaching 20 km in width. It is believed this valley was flooded with water in the past.
Olympus Mons
Olympus Mons is a large shield volcano on Mars. It is over 21.9 km high, as measured by the Mars Orbiter Laser Altimeter, and is about two and a half times Mount Everest's height above sea level.
| Geology of Mars | ||
|---|---|---|
| Plana | Aeolis Planum • Amenthes Planum • Aonia Planum • Argentea Planum • Ascuris Planum • Aurorae Planum • Bosporus Planum • Daedalia Planum • Hesperia Planum • Icaria Planum • Lucus Planum • Lunae Planum • Malea Planum • Meridiani Planum • Nepenthes Planum • Oenotria Planum • Olympia Planum • Ophir Planum • Oxia Planum • Parva Planum • Planum Angustum • Planum Australe • Planum Boreum • Planum Chronium • Promethei Planum • Sinai Planum • Sisyphi Planum • Solis Planum • Syria Planum • Syrtis Major Planum • Thaumasia Planum • Zephyria Planum | |
| Planitiae | Acidalia Planitia • Amazonis Planitia • Arcadia Planitia • Chryse Planitia • Elysium Planitia • Eridania Planitia • Isidis Planitia • Utopia Planitia | |
| Terrae | Aonia Terra • Arabia Terra • Terra Cimmeria • Margaritifer Terra • Noachis Terra • Promethei Terra • Terra Sabaea • Sirenum Terra • Tyrrhena Terra • Xanthe Terra | |
| Borealis | Vastitas Borealis | |
| Chaos | Hellas Chaos • Iani Chaos • Margaritifer Chaos | |
| Mountains | Aeolis Mons • Alba Mons • Apollinaris Mons • Arsia Mons • Ascraeus Mons • Elysium Mons • Noctis Mons • Olympus Mons • Pavonis Mons • Syria Mons | |
| Fossae | Alba Fossae • Claritas Fossae • Icaria Fossae • Sirenum Fossae | |
| Mensae | Cydonia Mensa • Deuteronilus Mensa • Protonilus Mensa | |
| Dorsae | Solis Dorsum | |
| Sulci | Lycus Sulci • Pavonis Sulci | |
| Labes | Candor Labes | |
| Rupes | Olympus Rupes | |
| Colles | Nili Colles • Scandia Colles | |
| Valles | Ares Valles • Kasei Valles • Maja Valles • Mamers Valles • Marikh Valles • Marte Valles • Reull Vallis • Shalbatana Valles • Simud Valles • Tiu Valles • Valles Marineris | |
| Undae | Tharsis Undae • Olympia Undae | |
| Craters | Antoniadi • Cassini • Dollfus • Gale • Greeley • Huygens • Jezero • Schiaparelli • Tikhonravov | |
| Basins | Hellas Basin • Argyre Basin | |
| Albedo Regions | Sinus Meridiani • Mare Erythraeum | |
| Other | Eridania Lake | |
Orbit/Rotation
Mars makes one orbit around the Sun in approximately 687 days. Mars' aphelion is around one hundred forty one million, five hundred thousand miles, or 1.2 AU from the Sun. The perihelion is around one hundred forty five million miles, or about 1.5 AU. Although, this orbit period can be perturbed by neighboring objects in the nearby Asteroid belt, and even the Earth.
Volcanism
The volcanic activity, more referred to as volcanism, has caused lava flows over the few millions of years, leaving behind trenches on the surface that can be viewed through even amateur telescopes on Earth. Examples of volcanism can be traced by to Olympus Mons, which is a possibly dormant shield volcano on the surface of Mars. It has not erupted in thousands of years, yet its last eruption shot a replete of debris into the atmosphere, causing a blackout for weeks. The lava is actually black.
Moons
Main Article: Moons of Mars
Mars harbors two moons in its gravitational pull, named Phobos and Deimos.
Phobos
Main Article: Phobos
Phobos, the larger and denser of the two, is home to the Stickney crater, a crater that is easily spotted to the right of the moon. Phobos was discovered by Asaph Hall in 1877.
Deimos
Main Article: Deimos
The next moon, Deimos, is the smaller and more irregular-shaped moon, which stands to reason that it was an inhabitant of the Asteroid belt. It was too discovered by Asaph Hall in the same year. It has two craters, Swift and Voltaire.
Gallery
See Also
| The Planets and Dwarf Planets | |
|---|---|
| Planets | |
| Inner: (Mercury • Venus • Earth • Mars) Outer: (Jupiter • Saturn • Uranus • Neptune) | |
| Dwarf Planets (and candidates) | |
| Ceres • Pluto • Haumea • Makemake • Quaoar • Orcus • Eris • Gonggong • Sedna | |