The Earth is the third planet of our Solar System and logically the one that at the moment we lived. Its size is something superior to the one of Venus and comprises of the terraqueous planets  Mars and Ceres along with. It has a period of transfering around the Sun of 365.24 days and one inclination of his axis of 23 what the year throughout entails change of stations every three months to us with variable temperatures. Its nitrogen atmosphere and I oxygenate for which the life has been able to be formed and to be developed, phenomenon that has at the moment not been able to repeat in any planet or satellite of our Solar System, although are indications of possible stable situation of life or possibility that there is it in the moon Io de Jupiter, Titan Saturn moon or the satellite Triton of Neptune. However in Mars, one assumes that it could have had some indication of life by the geologic images but is not had absolutely to the certainty of it, absolutely, continues being a pretty hypothesis.

            The planet Earth has an impressive Moon of size of 1/4 part of the Earth, but since we have defined in the Web, by the own Planet definition the Moon cannot be a planet because although the barycentre of theTierra-Luna system fulfills both conditions is within the surface of our planet; this case previously does not repeat in the case of Pluto and Charon moon; Charon, as it is indicated in the Web and according to the IAU it is already properly a Dwarf planet. That yes is spectacular observing it and among other phenomena the high tides as low due to the gravitational Moon field take place as much that exerts on our planet.

            Another curiosity of the Moon is that due to the proximity of the Earth and to its transfering around the same one it presents/displays the same rotation that transfering, that is to say, always presents/displays the same face to the Earth. In the past there was volcanic activity and it is observed if we watched the Moon dark zones that we called Seas whose name gave Galileo them thinking that there would be water (thing that lamentably does not have) and shining zones that is plagued of craters some of spectacular them observable all of them from the Earth with a small telescope. The best moment to observe craters is when the Moon is in the phase of first quarter or last quarter, because in both phases we observed better the dimension of craters and its depth with the shades that the tips and the mountains of the Moon reflect on the surface of the Moon.



Third planet of our Solar System



           In addition the Moon with a slight inclination to its axis on the plane of the ecliptic when orbiting in its 27 days and 1/3 around the Earth can hide in the Earth shade producing a wonderful Sun or Moon eclipse when it interposes between the Sun and we; usual but little always impressive phenomena.



Orbital characteristics
Average Dist. of the Sun 1.000 UA
Average radio 149.600.000 km
Eccentricity 0,017
Orbital period (sidereal) 365.26 days
Period of rotation 23h.56m.
Orbital speed average 29,79 km/s
Inclination of the axis 23,45
Number of satellites 1


Physical characteristics
Equatorial diameter 12,756 km
Mass 1.000 Earth
Average density 5,52 g/cm
Superficial gravity 1.00 Earth
Speed of escape 11,2 km/s
Average Temp. superf.: Day 58 C
Average Temp. superf.: Night -88 C
Atmosphere N2Or2



                    In the page Web you can obtain more data of each one of our planets and the dwarf planets defined by the IAU of our Solar System.


Masm Last update 2006-10-20)