The total lifespan for our sun (from birth to death) is estimated to beGroup of answer choices50 billion years10 billion years5 billion years30 million years

To determine the estimated total lifespan for our sun, we need to evaluate the provided options based on widely accepted astronomical data regarding stellar lifespans.

Lifespan of the Sun

1. Current Understanding: The sun is currently around 4.6 billion years old and is classified as a G-type main-sequence star (G dwarf) in its main sequence phase. Stars of this type have a well-established life cycle, and estimates suggest that they spend about 10 billion years in the main sequence phase, where they fuse hydrogen into helium.

2. Phases Beyond Main Sequence: After the main sequence phase, the sun will transition into the red giant phase, followed by shedding its outer layers and ending its life as a white dwarf. The total lifespan from birth to death of the sun, including its variations in different phases, is estimated to be around 10 billion years.

3. Evaluating Options: Considering the options provided:

   • 50 billion years: This is significantly longer than current estimates for any star like the sun.
   • 10 billion years: This aligns closely with astronomical estimates for the sun's total lifespan.
   • 5 billion years: This is shorter than the known age of the sun and its estimated lifespan.
   • 30 million years: This is far too brief for the lifespan of a star of this category.

Final Answer

The total lifespan for our sun (from birth to death) is approximately 10 billion years.