Terra Nova, known scientifically as Tau Ceti e, is the fourth planet in the Tau Ceti system, a star system just under 12 lightyears from Earth and is among the first extrasolar colonies in human history. Its colony settlement of Terra Nova, founded in 2260, expanded rapidly due to the early use of interstellar jump gates to facilitate trade and immigration. While Proxima Centauri b was the first extrasolar colony, Tau Ceti e was the first Type I Garden world to be colonised. It was officially incorporated as the Trust Territory of Terra Nova in 2267 and became a member state of the Terran Federation in 2381 as the Commonwealth of Terra Nova. It was re-designated a Province of the Terran Empire in 2600 and reincorporated as a Crown County in 2900. It became a member world of the Republic in 3275 as the Republic of Terra Nova. At a little over 3 Earth masses, it is a large world with roughly 74% of its surface covered by water in the form of large, stormy seas, rivers, and equatorial swampland. Its hot and humid climate is very beneficial for widespread agriculture, which helped greatly in establishing the human settler population.

The planet's star, Tau Ceti, is a G-class star with 78% of the Sun's mass and about half its luminosity. The closer distance of Terra Nova to its star, compared to that of Earth and the Sun, is offset by the relatively lower luminosity of Tau Ceti; it still receives 1.71 times the solar radiation as Earth, but its large size and insulating atmosphere absorb a great deal of this. As a result of these solar conditions and the abundance of liquid water, Terra Nova evolved a complex indigenous ecology of both flora and fauna that spread across the entirety of the planet before human colonisation. Initial human settlement sought to preserve and study this native life as much as possible, but the fast pace of immigration and the exploitation of the planet for natural resources and industry devastated the ecology. It is estimated that as much as 25% of the planet's native rainforests were destroyed before a moratorium was placed by the Terran government in industrial expansion in 2300. The ecological crisis was complicated by the Tau Ceti Conflict, a war between the autonomous Terran colonies in the system over competing rights to interplanetary resources.The effects of deforestation led to the extinction of a still-unknown number of native fauna species and changes in the planet's climate. Industrialisation restarted fifty years later during the lead-up to the Orion War of Independence, and Terra Nova became a major staging area for Terran Federal military action in the war. However, a concerted recovery effort and strict limitations on industrial development aided in repairing the damage done to the native ecology and climate.

During subsequent eras, Terra Nova remained a "stepping stone" into the wider Terran colonial empire. The human population grew gradually, with a large number of arcology-packed metropolises and a widely-distributed population of rural homesteaders and small industrial towns. The star system's low metallicity, and consequent low proportion of valuable heavy metal and rare earths on Terra Nova, limited industrial mining and large-scale heavy industry; after a period of economic decline in the 2900s and early 3000s, it has since developed a strong light-industrial manufacturing economy that specialises in producing fine and finished goods. It currently boasts a human population of 7.1 billion people.

Community content is available under CC-BY-SA unless otherwise noted.