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Summary

DescriptionTerrestrial planet sizes2.jpg	English: This diagram shows the approximate relative sizes of the terrestrial planets, from left to right: Mercury, Venus, Earth and Mars. Distances are not to scale. A terrestrial planet is a planet that is primarily composed of silicate rocks. The term is derived from the Latin word for Earth, "Terra", so an alternate definition would be that these are planets which are, in some notable fashion, "Earth-like". Terrestrial planets are substantially different from gas giants, which might not have solid surfaces and are composed mostly of some combination of hydrogen, helium, and water existing in various physical states. Terrestrial planets all have roughly the same structure: a central metallic core, mostly iron, with a surrounding silicate mantle. Terrestrial planets have canyons, craters, mountains, volcanoes and secondary atmospheres.
Date	3 August 2020, 05:22:28
Source	Mercury Globe-MESSENGER mosaic centered at 0degN-0degE.jpg Venus 2 Approach Image.jpg The Blue Marble (remastered).jpg OSIRIS Mars true color.jpg
Author	Mercury image: NASA/JHUAPL Venus image: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington Earth image: NASA/Apollo 17 crew, retouch by User:Aaron1a12 Mars image: ESA/MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA
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