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First image of Earth and the Moon from Mars (in orbit); notice South America is visible. [33] [6] March 11, 2004 Spirit Mars Exploration rover: First image taken of Earth from the surface of Mars and any celestial body other than the Moon. July 27, 2006 Cassini-Huygens: The Pale Blue Orb is the first image of Earth from Saturn. [59] October 8 ...
Earth formed about 4.54 billion years ago by accretion from the solar nebula, a disk-shaped mass of dust and gas left over from the formation of the Sun, which also created the rest of the Solar System. Initially, Earth was molten due to extreme volcanism and frequent collisions with other bodies.
The Blue Marble is a photograph of Earth taken on December 7, 1972, by either Ron Evans or Harrison Schmitt aboard the Apollo 17 spacecraft on its way to the Moon.Viewed from around 29,400 km (18,300 mi) from Earth's surface, [1] a cropped and rotated version has become one of the most reproduced images in history.
USA (NASA) OAO-2: 21 December 1968: First human excursion beyond low Earth orbit. First in-person observations of Earth from a distance. First Trans-Earth injection. USA (NASA) Apollo 8 [25] 24 December 1968 First human flight to another celestial body (the Moon) and to enter its gravitational influence. USA (NASA) Apollo 8 [25] January 1969
In 1862, the physicist William Thomson, 1st Baron Kelvin published calculations that fixed the age of Earth at between 20 million and 400 million years. [19] [20] He assumed that Earth had formed as a completely molten object, and determined the amount of time it would take for the near-surface temperature gradient to decrease to its present value.
The geological time scale (GTS), as defined by international convention, [3] depicts the large spans of time from the beginning of Earth to the present, and its divisions chronicle some definitive events of Earth history. Earth formed around 4.54 billion years ago, approximately one-third the age of the universe, by accretion from the solar nebula.
The geologic time scale, proportionally represented as a log-spiral with some major events in Earth's history. A megaannus (Ma) represents one million (10 6) years.. The geologic time scale or geological time scale (GTS) is a representation of time based on the rock record of Earth.
The earliest Earth crust probably forms similarly out of similar material. On Earth the pluvial period starts, in which the Earth's crust cools enough to let oceans form. c. 4,404 Ma – First known mineral, found at Jack Hills in Western Australia. Detrital zircons show presence of a solid crust and liquid water.