Carbon planet

A carbon planet , also known as a diamond planet or carbide planet , is a hypothetical form of a terrestrial exoplanet proposed by Marc Kuchner . Such a planet should be able to form from protoplanetary dust disks that are rich in carbon and poor in oxygen . According to the findings of planetary research, the development of such a planet should proceed differently than that of silicon- rich planets ( Earth , Venus, etc.).

definition

Similar to the silicon- rich earth , a carbon planet should also have an iron core. Shells of silicon carbide and titanium carbide should form around this core , on which in turn a thick layer of carbon should rest. This carbon layer is expected from graphite exist as well, if enough pressure is present to his generation, could diamonds in volcanic eruptions eject and veritable mountains form on the surface. Various hydrocarbons (e.g. methane ) and gases such as carbon monoxide should also be present on the surface .

Should water be present on such planets, a possibly developing life could have a metabolism that is, so to speak, the opposite of what is known from the earth: living beings would ingest oxygen as food and breathe it through the carbonaceous atmosphere .

Characteristics

Carbon planets should have a density similar to planets with a predominantly silicon-containing mantle. So it will be difficult to tell them apart. Geological structures such as rivers and mountains can also be present, albeit with other elements (e.g. seas that do not consist of water but of oils ). If the temperature does not exceed certain values (approx. 350 K , i.e. approx. 80 ° C), long-chain molecules could form, which should collect in the atmosphere and finally rain down on the surface.

The Terrestrial Planet Finder project planned by NASA should be able to discover carbon planets, if they exist.

Possible carbon planets

The pulsar PSR 1257 + 12 could be orbited by a carbon planet ( PSR 1257 + 12 b ).

In addition, one expects carbon planets near the galactic center , since stars there have a higher proportion of carbon than z. B. the sun . Due to the accumulation of elements with a higher atomic number over time (by nuclear fusion within the stars with subsequent release by supernovae ), the concentration of carbon there could already have reached the required level.

It is assumed that the exoplanet PSR J1719-1438b, discovered in August 2011, is a carbon planet , which, however, evolved from a star or white dwarf whose normal development was enormously disturbed by a nearby pulsar.

Web links

Ker Than: Star's Planets Might Have Mountains of Diamonds , Space.com. June 7, 2006.

Individual evidence

^ Scientists Model a Cornucopia of Earth-sized Planets. Goddard Space Flight Center , accessed August 15, 2018 .
↑ Marc J. Kuchner, S. Seager: Extrasolar Carbon Planets . In: arXiv . 2005. arxiv : astro-ph / 0504214 .
↑ Bailes M., Bates, SD, Bhalerao, VB, Bhat, NDR, Burgay M., Burke-Spolaor S., D'Amico N., Johnston S., Keith, MJ, Kramer M., Kulkarni, SR, Levin L., Lyne, AG, Milia S., Possenti A., Spitler L., Stappers B., van Straten W., Transformation of a Star into a Planet in a Millisecond Pulsar Binary , Science 2011, 333 , p. 1717– 1720 doi : 10.1126 / science.1208890 speaks of an "ultralow-mass carbon white dwarf"

[NasaGoddard-1] Scientists Model a Cornucopia of Earth-sized Planets. Goddard Space Flight Center , accessed August 15, 2018 .

[2] Marc J. Kuchner, S. Seager: Extrasolar Carbon Planets . In: arXiv . 2005. arxiv : astro-ph / 0504214 .

[3] Bailes M., Bates, SD, Bhalerao, VB, Bhat, NDR, Burgay M., Burke-Spolaor S., D'Amico N., Johnston S., Keith, MJ, Kramer M., Kulkarni, SR, Levin L., Lyne, AG, Milia S., Possenti A., Spitler L., Stappers B., van Straten W., Transformation of a Star into a Planet in a Millisecond Pulsar Binary , Science 2011, 333 , p. 1717– 1720 doi : 10.1126 / science.1208890 speaks of an "ultralow-mass carbon white dwarf"