Dictionary of Space Concepts

Short Definition
Terrestrial planets are rocky planets with solid surfaces, composed mainly of silicate rocks and metals. They are considered potentially habitable due to their location within the habitable zone of their star, this means that they are located at a distance from their star where the temperature is neither too hot nor too cold for liquid water to exist.

Detailed Definition
Terrestrial planets include Earth, Venus, Mars, and Mercury and typically have thin or no atmospheres, distinguishing them from gas giants. With relatively high densities compared to gas giants, terrestrial planets tend to exhibit a wide range of geological features, such as mountains, valleys, and impact craters.
Additionally, their relatively high densities contribute to their stronger gravitational pull, which affects not only their overall structure but also the dynamics of their planetary systems. It is likely that there were more terrestrial planets during the formation of our solar system, but they either merged with each other or were destroyed. Their unique characteristics and potential for habitability make terrestrial planets a subject of ongoing scientific study and appealing for potential colonization by humans in the future.

Etymology
The term "terrestrial planets" originates from the Latin word "terra," which means "earth" or "land." The word "terrestrial" itself is derived from the Latin adjective "terraeus," meaning "of the earth."

The word "planet" has its roots in ancient Greek. It comes from the Greek term "planētēs," which means "wanderer" or "wandering star."

Sample Sentence(s)

"It's unclear what the dividing line is between a rocky planet and a terrestrial planet."

Dutfield, S., & Gammon, K. (2022). Terrestrial planets: Definition & facts about the inner planets and beyond. Space.com. https://www.space.com/17028-terrestrial-planets.html

 

Translations of Terms/Concepts into Partner Languages

French
Planète tellurique

German
Terrestrische Planeten or Erdähnlicher Himmelskörper

Italian
Pianeta terrestre

Polish
Planety skaliste, planety typu ziemskiego

Swedish
Stenplanet

 

Additional Translations

Spanish

Planeta terrestre

Turkish

Karasal gezegen

Dutch

Aardse planeten

 

Links to Videos/Articles

Dutfield, S., & Gammon, K. (2022). Terrestrial planets: Definition & facts about the inner planets and beyond. Space.com. https://www.space.com/17028-terrestrial-planets.html

Morbidelli, A., Lunine, J. I., O’Brien, D. P., Raymond, S. N., & Walsh, K. J. (2012). Building Terrestrial Planets. Annual Review of Earth and Planetary Sciences, 40(1), 251–275. https://doi.org/10.1146/annurev-earth-042711-105319

Terrestrial | Planet Types – Exoplanet Exploration: Planets Beyond our Solar System. (n.d.). Exoplanet Exploration: Planets Beyond Our Solar System. https://exoplanets.nasa.gov/what-is-an-exoplanet/planet-types/terrestrial/

Cornerstone Television Network. (2015, October 8). Origins: The Terrestrial Planets [Video]. YouTube.

MooMooMath and Science. (2019, August 22). Terrestrial Planets in Order [Video]. YouTube.