Q1. Answer the following questions:
- (a)) The distance of planet Jupiter from the Sun is 5 AU. Express this distance in light year and parsec. (200 words)
- (b)) Calculate the ratio of the surface temperatures of the stars 1 and 2 from the following data: Star 1: Absolute magnitude 2, Radius (RO) 64; Star 2: Absolute magnitude 7, Radius (RO) 4. (200 words)
- 1 AU = 1.496 × 10⁸ km is the standard astronomical unit.
- 1 light year is the distance light travels in one year (approx. 9.468 × 10¹² km).
- 1 parsec = 3.26 light years, a larger unit for stellar distances.
- Absolute magnitude difference relates to luminosity ratio: M₂ - M₁ = -2.5 log₁₀(L₂/L₁).
Answer: The following response addresses two fundamental questions in astronomy and astrophysics: converting astronomical distances between common units and calculating the ratio of stellar surface temperatures using absolute magnitudes and radii. Both tasks require the application of key astronomical formulas and constants, as typically covered in the PHE-15 course. Understanding these concepts is crucial for comprehending the vast scales and physical properties of celestial objects.