Image: Terrestrial planet size comparisons

Description: 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. Français : Les planètes telluriques, de gauche à droite : Mercure, Vénus, Terre, et Mars. Italiano: Questo diagramma mostra approssimativamente le dimensioni relative dei pianeti terrestri, da sinistra a destra: Mercurio, Venere, Terra e Marte. Le distanze non sono in scala. Un pianeta terrestre è un pianeta composto per lo più di roccia e metalli. Il termine deriva direttamente dal nome del nostro pianeta (anche in latino), "Terra", quindi una definizione alternativa sarebbe che questi pianeti sonoin qualche modo simili alla Terra. I pianeti terrestri sono sostanzialmente diversi dai giganti gassosi, che potrebbero non avere una superficie solida e sono composti soprattutto di qualche combinazione di idrogeno, elio e acqua presenti in vari stati fisici. I pianeti terrestri hanno tutti più o meno la stessa struttura: un nucleo metallico, soprattutto ferroso, circondato da un mantello di silicato. I pianeti terrestri hanno canyon, crateri, montagne, vulcani e atmosfere secondarie.
Title: Terrestrial planet size comparisons
Credit: http://solarsystem.nasa.gov/multimedia/gallery/terr_sizes.jpg Uploaded to commons from the english wikipedia; description page was here 19:27, 20 March 2006 Brian0918 1500x653 (499,869 bytes) Also previously uploaded as Image:Terr sizes.jpg 17:34, 24 June 2005 RHorning 1,500×653 488 KB Comparison of sizes of the terrestrial planets.
Author: wikipedia user Brian0918
Permission: This file is in the public domain in the United States because it was solely created by NASA. NASA copyright policy states that "NASA material is not protected by copyright unless noted". (See Template:PD-USGov, NASA copyright policy page or JPL Image Use Policy.) Warnings: Use of NASA logos, insignia and emblems is restricted per U.S. law 14 CFR 1221. The NASA website hosts a large number of images from the Soviet/Russian space agency, and other non-American space agencies. These are not necessarily in the public domain. Materials based on Hubble Space Telescope data may be copyrighted if they are not explicitly produced by the STScI.[1] See also Template:PD-Hubble and Template:Cc-Hubble. The SOHO (ESA & NASA) joint project implies that all materials created by its probe are copyrighted and require permission for commercial non-educational use. [2] Images featured on the Astronomy Picture of the Day (APOD) web site may be copyrighted. [3] The National Space Science Data Center (NSSDC) site has been known to host copyrighted content even though its photo gallery FAQ states that all of the images in the photo gallery are in the public domain.
Usage Terms: Public domain
License: Public domain
Attribution Required?: No