Question

The age of our solar system is about (a) one-third of the age of the universe; (b) three-fourths of the age of the universe; (c) 2 billion years less than the age of the universe.

Short answer

The correct answer is option (a).

Step-by-step solution

Understanding the Problem

We need to determine which statement accurately describes the age of our solar system relative to the age of the universe. We have three options to consider.

Analyzing Option (a)

Option (a) suggests that the age of the solar system is one-third of the age of the universe. Since the universe is about 13.8 billion years old and the solar system is about 4.6 billion years old, check whether 4.6 is approximately one-third of 13.8. Calculation: \[ \frac{1}{3} \times 13.8 \approx 4.6 \]Hence, Option (a) seems correct.

Analyzing Option (b)

Option (b) suggests that the age of the solar system is three-fourths of the age of the universe. Check if 4.6 is approximately three-fourths of 13.8.Calculation:\[ \frac{3}{4} \times 13.8 = 10.35 \]Since 10.35 is not approximately equal to 4.6, Option (b) is incorrect.

Analyzing Option (c)

Option (c) states the solar system is 2 billion years less than the age of the universe. Check if 13.8 - 2 equals 4.6.Calculation:\[ 13.8 - 2 = 11.8 \]Since 11.8 is not equal to 4.6, Option (c) is incorrect.

Conclusion

Based on our calculations, Option (a) is the only correct statement that represents the age of the solar system as approximately one-third of the age of the universe.

Key concepts

Solar System Age

Our Solar System is a captivating celestial neighborhood. Scientists estimate it to be around 4.6 billion years old. This age is determined by studying the oldest meteorites and using radioactive dating techniques. Such dating involves analyzing isotopes and their decay rates, revealing how long these rocks have existed.
Understanding the age of the Solar System is crucial for piecing together cosmic history. By knowing its age, we can explore how planets, moons, and other celestial bodies formed and evolved.
It also helps astronomers cross-reference the formation of our Solar System with others in the universe. This knowledge contributes to uncovering the mysteries of our existence and the dynamics of the universe.

Universe Age

The universe has been around for approximately 13.8 billion years. This age is not just a random guess—scientists determine it through meticulous observations. One pivotal method is examining the Cosmic Microwave Background Radiation, which is the leftover heat from the Big Bang.
The expansion rate of the universe, described by the Hubble constant, is another critical element in understanding the universe's age. By observing the speeds at which galaxies move apart, astronomers can rewind cosmic history to estimate its birth time.
Understanding the universe's age offers insights into its evolution, from the Big Bang to the formation of galaxies, stars, and eventually, systems like our Solar System. It is crucial for contextualizing where we come from and where we're headed in this vast cosmos.

Cosmology

Cosmology is the branch of astronomy that delves into the universe's origins, structure, evolution, and eventual fate. It's like being a detective, piecing together the story of everything around us. Scientists in this field explore fundamental questions about the cosmos.
Key concepts in cosmology include:

• The Big Bang Theory, which suggests the universe started from an incredibly hot and dense single point.
• Dark matter and dark energy, mysterious components that make up most of the universe.
• The expansion of the universe, a discovery credited to observing distant galaxies speeding away from us.

By studying these elements, cosmology helps us understand not only the physical makeup of the universe but also the laws governing it. It's an exhilarating field that keeps evolving as new observations and technologies emerge, continually reshaping our understanding of the universe.