Short Term:
* No More Fusion: The Sun's energy production relies on nuclear fusion, which converts hydrogen into helium. Without hydrogen, fusion would cease, and the Sun would no longer produce light and heat.
* Rapid Cooling and Contraction: The Sun would begin to cool and contract under its own gravity. This contraction would cause the Sun's core to heat up significantly.
* Red Giant Phase: The Sun would expand greatly, becoming a red giant star. It would engulf the inner planets, including Mercury, Venus, and possibly Earth.
Long Term:
* White Dwarf: After its red giant phase, the Sun would shed its outer layers, leaving behind a small, dense white dwarf. This white dwarf would be incredibly hot but would slowly cool over billions of years.
* Planetary Nebula: The expelled material from the Sun would form a beautiful, expanding cloud of gas and dust known as a planetary nebula.
* No Life: Without the Sun's heat and light, all life on Earth would cease to exist.
In summary, the Sun's transformation from hydrogen to helium would be a cataclysmic event, ultimately leading to the death of our star and the destruction of our solar system as we know it.
Important Note: This process would take billions of years. The Sun is still in its hydrogen-burning phase, and it will continue to do so for billions of years more.
