1. What is Orbital Velocity?

Orbital velocity is the speed needed for an object to maintain a stable orbit around Earth (or another celestial body) at a given altitude. It balances the gravitational pull with the object's inertia.

2. How Does the Calculator Work?

The calculator uses the orbital velocity equation:

Where:

• \( v \) — Orbital velocity (m/s)
• \( G \) — Gravitational constant (6.67430 × 10⁻¹¹ m³/kg·s²)
• \( M_{earth} \) — Mass of Earth (5.972 × 10²⁴ kg)
• \( r \) — Orbital radius from Earth's center (m)

Explanation: The equation shows that orbital velocity decreases as the distance from Earth increases.

3. Importance of Orbital Velocity

Details: Calculating orbital velocity is essential for satellite deployment, space mission planning, and understanding celestial mechanics.

4. Using the Calculator

Tips: Enter the orbital radius in meters (distance from Earth's center to the orbiting object). For altitude above Earth's surface, add Earth's radius (~6,371 km).

5. Frequently Asked Questions (FAQ)

Q1: What's the orbital velocity at Earth's surface?
A: Approximately 7.9 km/s (7900 m/s), known as the first cosmic velocity.

Q2: How does altitude affect orbital velocity?
A: Higher orbits have lower orbital velocities. For example, geostationary orbit (~35,786 km altitude) has velocity of about 3.07 km/s.

Q3: What's the difference between orbital velocity and escape velocity?
A: Escape velocity (√2 times orbital velocity) is the speed needed to break free from Earth's gravity completely.

Q4: Does the object's mass affect orbital velocity?
A: No, orbital velocity is independent of the orbiting object's mass (assuming it's much smaller than Earth's mass).

Q5: What about circular vs elliptical orbits?
A: This calculator gives velocity for circular orbits. Elliptical orbits have varying speed (faster at perigee, slower at apogee).