Editing Terrestrial planet (section)

==Types==
{{Further|List of planet types}}
[[File:Carbon Planet.JPG|thumb|right|Artist's impression of a [[carbon planet]]]]
Several possible classifications for solid planets have been proposed.<ref>{{Cite web|url = http://www.nasa.gov/centers/goddard/news/topstory/2007/earthsized_planets.html|title = Scientists Model a Cornucopia of Earth-sized Planets|date = 24 September 2007|access-date = 23 October 2013|last = Naeye|first = Bob|publisher = NASA, Goddard Space Flight Center|url-status = live|archive-url = https://web.archive.org/web/20120124000809/http://www.nasa.gov/centers/goddard/news/topstory/2007/earthsized_planets.html|archive-date = 24 January 2012|df = dmy-all}}</ref>

; Silicate planet
: A solid planet like Venus, Earth, or Mars, made primarily of a silicon-based rocky mantle with a metallic (iron) core.
; Carbon planet (also called "diamond planet")
{{main|Carbon planet}}
: A theoretical class of planets, composed of a metal core surrounded by primarily carbon-based minerals. They may be considered a type of terrestrial planet if the metal content dominates. The Solar System contains no carbon planets but does have [[C-type asteroid|carbonaceous asteroids]], such as Ceres and [[10 Hygiea|Hygiea]]. It is unknown if Ceres has a rocky or metallic core.<ref name=Dawn2017>{{Cite web|url=http://sites.nationalacademies.org/cs/groups/ssbsite/documents/webpage/ssb_183286.pdf |archive-url=https://web.archive.org/web/20180413174709/http://sites.nationalacademies.org/cs/groups/ssbsite/documents/webpage/ssb_183286.pdf |archive-date=2018-04-13 |url-status=live|title=''Dawn'' at Ceres: What Have We Learned?|work=NASA, JPL |author=JC Castillo Rogez |author2=CA Raymond |author3=CT Russell |author4=Dawn Team|date=2017|access-date=2021-07-19}}</ref>
; Iron planet
{{main|Iron planet}}
: A theoretical type of solid planet that consists almost entirely of iron and therefore has a greater density and a smaller radius than other solid planets of comparable mass. Mercury in the Solar System has a metallic core equal to 60–70% of its planetary mass, and is sometimes called an iron planet,<ref>{{cite journal |last1=Hauck |first1=Steven A. |last2=Johnson |first2=Catherine L. |author-link2=Catherine Johnson (scientist)|date=2019 |title=Mercury: Inside the Iron Planet |journal=Elements |volume=15 |issue=1 |pages=21–26 |doi=10.2138/gselements.15.1.21|bibcode=2019Eleme..15...21H |s2cid=135208562 }}</ref> though its surface is made of silicates and is iron-poor. Iron planets are thought to form in the high-temperature regions close to a star, like Mercury, and if the protoplanetary disk is rich in iron.
; Icy planet
{{Main|Ice planet}}
[[File:Fountains of Enceladus PIA07758.jpg|thumb|right|Geysers erupting on Enceladus]]
: A type of solid planet with an icy surface of volatiles. In the Solar System, most [[planetary-mass moon]]s (such as Titan, Triton, and Enceladus) and many dwarf planets (such as Pluto and Eris) have such a composition. Europa is sometimes considered an icy planet due to its surface ice, but its higher density indicates that its interior is mostly rocky. Such planets can have internal saltwater oceans and [[cryovolcano]]es erupting liquid water (i.e. an internal hydrosphere, like Europa or Enceladus); they can have an atmosphere and hydrosphere made from methane or nitrogen (like Titan). A metallic core is possible, as exists on Ganymede.<ref name=planetarysociety/>
; Coreless planet
{{main|Coreless planet}}
: A theoretical type of solid planet that consists of silicate rock but has no metallic core, i.e. the opposite of an iron planet. Although the Solar System contains no coreless planets, [[chondrite]] asteroids and meteorites are common in the Solar System. Ceres and Pallas have mineral compositions similar to carbonaceous chondrites, though Pallas is significantly less hydrated.<ref name="Marsset2020">{{cite journal | last1=Marsset | first1=Michaël | last2=Brož | first2=Miroslav | last3=Vernazza | first3=Pierre | last4=Drouard | first4=Alexis | last5=Castillo-Rogez | first5=Julie | last6=Hanuš | first6=Josef | last7=Viikinkoski | first7=Matti | last8=Rambaux | first8=Nicolas | last9=Carry | first9=Benoît | last10=Jorda | first10=Laurent | title=The violent collisional history of aqueously evolved (2) Pallas | journal=Nature Astronomy | publisher=Springer Science and Business Media LLC | volume=4 | issue=6 | date=2020-02-10 | issn=2397-3366 | doi=10.1038/s41550-019-1007-5 | pages=569–576 | bibcode=2020NatAs...4..569M | hdl=10261/237549 | s2cid=256706529 |display-authors=2| hdl-access=free }}</ref> Coreless planets are thought to form farther from the star where volatile oxidizing material is more common.