2012

[venture]

How does it grow when it's fuel is itself? When it burns long enough, it will run out of fuel. Don't dieing stars explode when they run out of gas?

Wiki actually has a good article on this: Red giant - Wikipedia, the free encyclopedia

Source: Zeilik, Michael A.; Gregory, Stephan A. (1998). Introductory Astronomy & Astrophysics (4th ed.). Saunders College Publishing. pp. 321–322. ISBN 0030062284.

When the star exhausts the hydrogen fuel in its core, nuclear reactions in the core stop, so the core begins to contract due to its gravity. This heats a shell just outside the core, where hydrogen remains, initiating fusion of hydrogen to helium in the shell. The higher temperatures lead to increasing reaction rates, producing enough energy to increase the star's luminosity by a factor of 1,000–10,000. The outer layers of the star then expand greatly, beginning the red giant phase of the star's life. Due to the expansion of the outer layers of the star, the energy produced in the core of the star is spread over a much larger surface area, resulting in a lower surface temperature and a shift in the star's visible light output towards the red — hence red giant, even though the color usually is orange. At this time, the star is said to be ascending the red giant branch of the Hertzsprung-Russell (H-R) diagram.

The Sun is expected to become a red giant in approximately five billion years.[7] It is calculated that the Sun will become sufficiently large to engulf the current orbits of the solar system's inner planets, up to Earth,[11][12][13] and its radius will expand to a minimum of 200 times its current value.[14] The Sun will lose a significant fraction of its mass in the process of becoming a red giant, and there is a chance that Mars and all the outer planets will escape as their resulting orbits will widen.[15] Mercury and most likely Venus will have been swallowed by sun's outer layer at this time. Earth's fate is less clear. Earth could technically achieve a widening of its orbit and could potentially maintain a sufficiently high angular velocity to keep it from becoming engulfed. In order to do so, its orbit needs to increase to between 1.3 AU (190,000,000 km) and 1.7 AU (250,000,000 km).[16] However the results of studies announced in 2008 show that due to tidal interaction between sun and Earth, Earth would actually fall back into a lower orbit, and get engulfed and incorporated inside the sun before the sun reaches its largest size, despite the sun losing about 38% of its mass.[17] Before this happens, Earth's biosphere will have long been destroyed by the Sun's steady increase in brightness as its hydrogen supply dwindles and its core contracts, even before the transition to a Red Giant. After just over 1 billion years, the extra solar energy input will cause Earth's oceans to evaporate and the hydrogen from the water to be lost permanently to space, with total loss of water by 3 billion years.[18] Earth's atmosphere and lithosphere will become like that of Venus. Over another billion years, most of the atmosphere will get lost in space as well;[15] ultimately leaving Earth as a desiccated, dead planet with a surface of molten rock.

[Richard at Remax]

as a geologist the whole notion of the day after tomorrow offends me. only trying to capiltalize on the al gore success of an inconvienent truth. which turned out to be false because the scientists left out chunks of data that would have proved it is all a fabrication.

[venture]

as a geologist the whole notion of the day after tomorrow offends me. only trying to capiltalize on the al gore success of an inconvienent truth. which turned out to be false because the scientists left out chunks of data that would have proved it is all a fabrication.

It was a movie that was entertaining, nothing more than that - is how I took it. I think until we have the ability to actually see clear real time images of what is going on beneath our feet, a lot of what we know is a crap shoot. Unfortunately I don't believe there is any ability to show real time imagining of fault lines, magma chambers, etc. I know we have ground-penetrating radar...but nothing like the current network of weather radars that would show faults, magma, other things under us and detect stress/movement.

[kevinpate]

.oO(Am I a horrid bit of dust bunny to not care about 5 billion years out?)Oo.