1. What is Surface Gravity?

Surface gravity (g) is the gravitational acceleration experienced at the surface of an astronomical body. It determines the weight of objects on that body and influences atmospheric retention and other physical processes.

2. How Does the Calculator Work?

The calculator uses the surface gravity equation:

Where:

• \( g \) — Surface gravity (m/s²)
• \( G \) — Gravitational constant (6.67430 × 10⁻¹¹ N·(m/kg)²)
• \( M \) — Mass of the planet (kg)
• \( r \) — Radius of the planet (m)

Explanation: The equation shows that surface gravity is directly proportional to the mass of the body and inversely proportional to the square of its radius.

3. Importance of Surface Gravity Calculation

Details: Surface gravity is crucial for understanding planetary characteristics, potential for atmosphere retention, and planning space missions. It also helps in comparing different celestial bodies.

4. Using the Calculator

Tips: Enter mass in kilograms and radius in meters. Both values must be positive numbers. For Earth, mass is 5.972 × 10²⁴ kg and radius is about 6.371 × 10⁶ m.

5. Frequently Asked Questions (FAQ)

Q1: What is Earth's surface gravity?
A: Earth's standard gravity is approximately 9.80665 m/s², though it varies slightly by location.

Q2: How does surface gravity affect weight?
A: Weight = mass × gravity. An object with mass 1 kg weighs 9.81 N on Earth but only 1.62 N on the Moon.

Q3: Why is surface gravity important for space missions?
A: It determines the thrust needed for takeoff and landing, and affects how equipment and astronauts function.

Q4: Can surface gravity be negative?
A: No, gravity is always attractive (positive value in calculations).

Q5: How does surface gravity relate to escape velocity?
A: Higher surface gravity means higher escape velocity is needed to leave the planet's gravitational pull.