VENUS IS THE HOTTEST PLANET WITH AN AVERAGE SURFACE TEMPERATURE OF ABOUT 737 K

Venus is the hottest planet with an average surface

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VENUS IS THE HOTTEST PLANET, WITH AN AVERAGE SURFACE TEMPERATURE OF ABOUT 737 K (464°C).
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THE INNER PLANETS VENUS SURFACE WHEN THE MAGELLAN ORBITER MAPPED THE SURFACE OF VENUS, IT REVEALED THAT VENUS HAS A SURFACE SMOOTHED BY VOLCANIC LAVA FLOWS AND WITH FEW IMPACT CRATERS. UNLIKE EARTH, THERE IS LITTLE EVIDENCE OF CURRENT TECTONIC ACTIVITY ON VENUS, AND THERE IS NO WELL-DEFINED SYSTEM OF CRUSTAL PLATES.
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THE INNER PLANETS VENUS INTERIOR ASTRONOMERS THEORIZE THAT VENUS HAS A LIQUID METAL CORE THAT EXTENDS HALFWAY TO THE SURFACE. DESPITE THIS CORE, VENUS HAS NO MEASURABLE MAGNETIC FIELD, PROBABLY BECAUSE OF ITS SLOW ROTATION, EQUIVALENT TO 243 EARTH DAYS.
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THE INNER PLANETS EARTH EARTH’S DISTANCE FROM THE SUN AND ITS NEARLY CIRCULAR ORBIT ALLOW WATER TO EXIST ON ITS SURFACE IN ALL THREE STATES—SOLID, LIQUID, AND GAS. LIQUID WATER IS REQUIRED FOR LIFE. IN ADDITION, EARTH’S MILD GREENHOUSE EFFECT AND MODERATELY DENSE ATMOSPHERE OF NITROGEN AND OXYGEN PROVIDE CONDITIONS SUITABLE FOR LIFE.
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THE INNER PLANETS EARTH EARTH IS THE MOST DENSE AND THE MOST TECTONICALLY ACTIVE OF THE TERRESTRIAL PLANETS. IT IS THE ONLY PLANET WHERE PLATE TECTONICS OCCURS.
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THE INNER PLANETS MARS MARS IS OFTEN REFERRED TO AS THE RED PLANET BECAUSE OF ITS REDDISH SURFACE COLOR. IT IS SMALLER AND LESS DENSE THAN EARTH AND HAS TWO IRREGULARLY SHAPED MOONS—PHOBOS AND DEIMOS.
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THE INNER PLANETS MARS ATMOSPHERE MARS AND VENUS HAVE ATMOSPHERES OF SIMILAR COMPOSITION. THE DENSITY AND PRESSURE OF THE ATMOSPHERE ON MARS ARE MUCH LOWER; THEREFORE, MARS DOES NOT HAVE A STRONG GREENHOUSE EFFECT LIKE VENUS DOES.
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THE INNER PLANETS MARS SURFACE THE SOUTHERN HEMISPHERE OF MARS IS A HEAVILY CRATERED, HIGHLAND REGION RESEMBLING THE HIGHLANDS OF THE MOON. THE NORTHERN HEMISPHERE HAS SPARSELY CRATERED PLAINS. FOUR GIGANTIC SHIELD VOLCANOES ARE LOCATED NEAR THE EQUATOR, NEAR A REGION CALLED THE THARSIS PLATEAU.
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THE INNER PLANETS MARS SURFACE AN ENORMOUS, 4000-KM-LONG CANYON, VALLES MARINERIS, LIES ON THE MARTIAN EQUATOR, SPLITTING THE THARSIS PLATEAU. IT PROBABLY FORMED AS A FRACTURE DURING A PERIOD OF TECTONIC ACTIVITY 3 BYA, WHEN THE THARSIS PLATEAU WAS UPLIFTED.
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THE INNER PLANETS MARS SURFACE OTHER MARTIAN SURFACE FEATURES INCLUDE DRIED RIVER AND LAKE BEDS, OUTFLOW CHANNELS, AND RUNOFF CHANNELS. THESE EROSIONAL FEATURES SUGGEST THAT LIQUID WATER ONCE EXISTED ON THE SURFACE OF MARS.
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THE INNER PLANETS MARS SURFACE THE ICE CAPS THAT COVER BOTH POLES ON MARS GROW AND SHRINK WITH THE SEASONS. THE CAPS ARE MADE OF CARBON DIOXIDE ICE, SOMETIMES CALLED DRY ICE. WATER ICE LIES BENEATH THE CARBON DIOXIDE ICE IN THE NORTHERN CAP.
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THE INNER PLANETS MARS INTERIOR ASTRONOMERS HYPOTHESIZE THAT MARS HAS A CORE OF IRON, NICKEL, AND POSSIBLY SULFUR THAT EXTENDS SOMEWHERE BETWEEN 1200 KM AND 2400 KM FROM THE CENTER OF THE PLANET.
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