Glossary term: Tierra
Description: La Tierra es el tercer planeta desde el Sol y el quinto más grande del Sistema Solar. Es un planeta rocoso y terrestre con un radio de unos 6 400 kilómetros (km). Tiene una masa de unos seis billones de billones de kilogramos.
La distancia típica de la Tierra al Sol es de unos 150 millones de kilómetros. Esto se define como una unidad astronómica. La Tierra tarda 365.26 días en completar una órbita alrededor del Sol. La Tierra tiene un satélite natural conocido como la Luna.
La Tierra alberga millones de especies de seres vivos, incluidos los humanos; es el único lugar conocido hasta la fecha en el que hay vida en el Universo. Se cree que se formó hace unos 4.54 miles de millones de años. La Tierra tiene una atmósfera y una magnetosfera que actúan para bloquear la radiación dañina y, por lo tanto, permiten la multiplicación de los organismos vivos. La Tierra también cuenta con una gran cantidad de agua en su superficie (es el único planeta del Sistema Solar del que se sabe que la tiene), lo que le da un color azul.
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Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher The translation of this term and its definition is still awaiting approval
The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".
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Credit: NASA/Apollo 17 crew/Project Apollo Archive
License: PD Public Domain icons
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Credit: NASA
credit link
License: PD Public Domain icons
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