1. Average distance from Earth to Sun in terms of parsec:

The average distance from Earth to the Sun is commonly referred to as an astronomical unit (AU), which is approximately 149.6 million kilometers. To express this distance in terms of parsecs, we need to convert AU to parsecs.

- 1 parsec (pc) is defined as the distance at which 1 astronomical unit subtends an angle of 1 arcsecond.
- 1 arcsecond is equal to 1/3600th of a degree.

Using basic trigonometry, we can calculate the distance in parsecs:

1 pc = (1 AU) / tan(1 arcsecond)

The tangent of 1 arcsecond is a very small angle, approximately 2.908882 x 10^-6. Thus, the formula becomes:

1 pc ≈ (1 AU) / (2.908882 x 10^-6)

Calculating this value:

1 pc ≈ (149.6 x 10^6 km) / (2.908882 x 10^-6)
≈ 5.135616 x 10^13 km

Therefore, the average distance from Earth to the Sun is approximately 5.135616 x 10^13 kilometers, or 1 parsec.

2. Average distance from Earth to Sun in terms of light year:

A light year is the distance that light travels in one year, which is approximately 9.461 trillion kilometers. To express the average distance from Earth to the Sun in terms of light years, we need to convert AU to light years.

- 1 light year (ly) is equal to the distance that light travels in one year.
- The speed of light is approximately 299,792 kilometers per second.

Using this information, we can calculate the distance in light years:

1 ly = (1 AU) / (299,792 km/s) * (1 year)

1 year ≈ 31,536,000 seconds (taking into account leap years)

Therefore,

1 ly ≈ (149.6 x 10^6 km) / (299,792 km/s) * (31,536,000 s)
≈ 4.84814 x 10^-6 km

Hence, the average distance from Earth to the Sun is approximately 4.84814 x 10^-6 light years.

In summary, the average distance from Earth to the Sun is approximately 1 parsec or 4.84814 x 10^-6 light years.

Light year