If the Sun produces more light and heat it will affect Earth greatly. The Sun contains enough hydrogen to last ten billion years. The Sun needs all the hydrogen because it nuclear fuses hydrogen atoms together in its core to make helium which produces energy. The outward pressure created by the energy emitted from the fusion cancels out the inward pull of gravity, this is how the Sun stays stable. Once it runs out of the hydrogen in the core, it will go through changes where it will start fusing hydrogen in the outside of the Sun and will release more heat and light.
The Sun goes though many phases as it begins to burn hydrogen outside of the core. Over time the Sun will begin to get larger and will start to change colors. It gets larger because the hydrogen being fused is producing greater energy than the gravity, when this happens the Sun will be known as a red giant. This phase also causes the Sun to turn a dark red-orange, which is where the name ‘red giant’ comes from. This phase of the Sun could really affect the fate of our solar system. Figure 1 shows how the luminosity, which is the energy from the Sun, changes over time as the Sun approaches the red giant phase. The dotted line represents where we are at currently in the Sun’s lifetime (we are currently at the 4.5 billion years point). In the 8 billion year point the luminosity is roughly 1.5 times greater than the Sun currently is. The figure ends at 10 billion years because there is to much dramatic stuff happening to record when its at the red giant phase.
Since the Sun is producing more energy it will overheat the Earth which means the water on Earth will evaporate. This evaporation will happen before the red giant phase and most likey in the next 1 billion years. If the Sun grows too large in the red giant phase we, Earth, would be “in” the Sun (which means destruction of the entire Earth). Besides Earth getting dried up or destroyed, Mercury, Venus, and Mars also will be burnt and/or obliterated. The other outer planets will also get warmer due to the power of the “new” Sun. That could affect the climate of these planets and their moons as well, such as a very cold planet could become a new, cool or warm one because of the extra heat. Some of these places would become livable environment for mankind, if we survive for that long.
1. In figure 1, in the year 10 billion what is expected luminosity to be at?
2. What is the source of energy of the Sun after the core runs out of hydrogen?
3. What is are the two outcomes of the Earth as the Sun changes, which would happen first?