Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.armaghplanet.com/pdf/AstroTopics/Solar%20System/Deeptime.pdf Дата изменения: Tue Sep 20 18:49:56 2011 Дата индексирования: Tue Oct 2 01:13:38 2012 Кодировка: Поисковые слова: water

Deep Time: Earth's history and future By Colin Johnston, Armagh Planetarium

Earth 4.54 billion years ago Forms in Sun's protoplanetary disc

S un

Elsewhere in Solar System Other planets form. There are at least five rocky inner planets. The four giant planets' orbits are relatively tightly clustered between the present day orbits of Jupiter and Saturn.

4.527 billion years ago

4.5-4 billion years ago

Collision with other planet; Formation of the Moon from debris Mainly carbon dioxide atmosphere, surface water, molten core and magnetic field Earliest oceans of water existed

Mars also has a mainly carbon dioxide atmosphere, surface water, molten core and magnetic field

4.2 billion years ago 4-3.8 billion years ago

Gravitational interactions between giant plants cause them to migrate to present positions, sweep debris to present day Asteroid and Kuiper Belts. Late Heavy bombardment: `storm' of asteroid impacts on inner planets Earliest life in oceans? First photosynthetic life? Atmosphere becoming rich in oxygen Sun's luminosity is about 89% current v a lue Sun's luminosity is 1

3 3 3 2

.8 billion yea .5 billion yea billion years .4 billion yea

rs ago rs ago ago rs ago

2 billion years ago

1 billion years ago

Earth's biological


productivity peaks 470 million years ago Now First plant and animal life on land? Thick, mainly nitrogen and oxygen atmosphere, extensive liquid water, molten core generating magnetic field

about 95% present v a lue

400 million years from no w 700 million years from no w ?

Saturn's ring have dwindled to nothing Mean temperature is 40°C. Declining atmospheric levels of carbon dioxide causes extinction of most plants and animals on land. As a result atmospheric oxygen levels decrease. Mean temperature is 70°C, oceans shrinking, bacteria the only lifeforms, beginning of `moist greenhouse' Earth's oceans boiling, conditions on Earth eventually resemble those of present day Venus. Mean temperature is 370°C, Final extinction of life? Earth and Moon tidally locked

1 billion years from no w ?

Sun is 10% brighter than it is now

1.2 billion years from no w ?

2 billion years from no w ? 3.5 billion years from no w ? 4 billion years from no w ? 5 billion years from no w ?

Triton breaks up, Neptune gains spectacular new rings Milky Way and Andromeda galaxies collide Milky Way and Andromeda have merged into a giant elliptical galaxy ­ `Milkomeda'? Hot and airless Sun a subgiant, diameter 1.5 its current value, 2

6.4 billion years from no w ?


7 billion years from no w ?

Sun's reduction in mass means Earth's orbital radius has increased to 1.4 times its current value, surface temperature is about 1400°C

luminosity twice its current value Sun moves into red giant phase, diameter about 160 million km

Mercury absorbed by expanding Sun, Venus probably meets the same fate, icy moons of Jupiter vaporised, icy Kuiper Belt Objects melt

7.6 billion years from no w ?

7.7 billion years from no w ?

Earth cools

20 million years later?

Earth destroyed?

7.8 billion years from no w ?

Core temperature about 55 million°C, helium flash, followed by the Sun shrinking Sun is 10 times its current diameter, luminosity 20-50% current value. Helium burning in core. Sun burning carbon and oxygen in core, expands to red giant again. Diameter 240 million km, luminosity 3000 times current value. Sun goes through series of helium flashes (3 or 4), swelling and losing mass each time Sun a white dwarf surrounded by planetary nebula which disperse over thousands of years.

Gas giant planets still s ur v iv e

500 billion years from no w 1 quadrillion (1015) years from now? Further reading Plait, Philip, Death from the skies! Viking Penguin, New York, 2008

Milkomeda and other galaxies in the Local Group have merged into one huge galaxy Sun cooled to a black dw a r f

Ward, Peter and Brownlee, Donald, The life and death of planet Earth, Paitkus, London, 2007 3


Adams, Fred and Laughlin, Greg, the five ages of the universe, The Free Press, New York, 1999 http://www.psrd.hawaii.edu/Aug06/cataclysmDynamics.html

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