Earth
According to Greek mythology, Earth is Gaia, who was born just after Chaos. We now know that it is the largest planet among the smallest. It is the only inhabited planet we know, although we know of thousands of planets around other stars. As a tiny island lost in the middle of an immense cosmos, we have no choice but to treat our Mother Earth well.
| Diameter | The Earth is 12,742 km in diameter and here it is 1.3 cm. On this scale, a chickpea would be somewhat larger than the one represented by Venus. |
| Duration of the day | The solar day is 24 hours. In reference to the stars, a full rotation takes place in 23 h 56 m. |
| Year duration | The Earth makes a complete revolution around the the Sun in 365.25 days. Every four years we add this quarter turn to add one day at the end of February. |
| Distance of the sun | 149.6 million km. This value defines the Astronomical Unit (AU). |
| Satellites | One, the Moon, located about 384,000 km. On this scale this corresponds to 38.4 cm, a value much smaller than the diameter of the Sun: a 1.40 m sphere located inside the observatory. |
| Composition | Despite the large presence on the surface, it is a relatively water-poor planet. It is a solid planet made mostly of oxygen, magnesium, silicon, iron, aluminum, calcium, and nickel. |
| The best-documented temperature extremes are minus 89 °C in Antarctica and positive 57 °C in the Death Valley in North America. |
| Density | It is the planet with the highest average density of all: 5.5 g / cm³. |
| Did you know... | … That considering the latitude where we are located (41.5 °), every day we go around 30,000 km? This speed causes the masses of air and water to be affected by an acceleration called Coriolis. The consequence in the circulation of the clouds can be seen in the weather maps. |
