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Escape Velocity Calculator – Calculate Escape Velocity

Calculate the escape velocity needed to break free from a celestial body's gravitational pull. Our calculator uses the formula ve = √(2GM/R).

How to Calculate Escape Velocity

Step 1: Enter the mass of the celestial body in kilograms.

Step 2: Enter the radius from the center to the surface in meters.

Step 3: Click Calculate to see the escape velocity needed to break free from gravity.

Understanding Escape Velocity

What Is Escape Velocity

Escape velocity is the minimum speed needed to break free from a planet or moon's gravity without further propulsion. It's not about direction - you can go straight up or at an angle. Once you reach escape velocity, you'll keep going forever (unless another gravity well catches you). Earth's escape velocity is 11.2 km/s - about 25,000 mph.

The Formula Explained

Escape velocity comes from equating kinetic energy to gravitational potential energy:

v_e = √(2GM/R)

G is the gravitational constant (6.674×10⁻¹¹), M is the body's mass, R is the radius. More mass means higher escape velocity. Larger radius (for the same mass) means lower escape velocity.

Escape Velocity vs Orbital Velocity

Orbital velocity is what keeps satellites circling Earth - about 7.8 km/s for low Earth orbit. Escape velocity is √2 times orbital velocity - about 11.2 km/s. Satellites stay in orbit. Escape velocity objects leave forever.

Escape Velocities of Celestial Bodies
BodyEscape VelocityNotes
Moon2.38 km/sEasy to launch from
Mars5.03 km/sLess than half of Earth's
Venus10.36 km/sSimilar to Earth
Earth11.19 km/s25,020 mph
Saturn36.09 km/sGas giant
Jupiter60.20 km/sHighest in solar system
Sun617.5 km/sFrom surface (photosphere)

Black holes have escape velocities greater than the speed of light - which is why nothing escapes them.

Frequently Asked Questions

What is Earth's escape velocity?

Earth's escape velocity is 11.2 km/s (25,020 mph or 40,270 km/h). This is the speed a rocket needs at Earth's surface to escape Earth's gravity without further propulsion.

Does escape velocity depend on the object's mass?

No. A feather and a rocket need the same escape velocity from the same planet. The planet's mass matters, not the escaping object's mass. Gravity pulls harder on heavier objects, but they also need more energy to accelerate - these effects cancel out.

Can you escape gravity at any speed?

With continuous propulsion, yes. Escape velocity is the speed needed for a ballistic (unpowered) trajectory. Rockets don't reach 11.2 km/s instantly - they accelerate continuously, burning fuel as they climb.

What happens if you go slower than escape velocity?

You'll either fall back down or go into orbit. Below escape velocity but above orbital velocity, you follow an elliptical path that eventually returns you to the starting point (unless you hit the planet first).

Why is escape velocity higher for gas giants?

Gas giants like Jupiter are much more massive than Earth. Jupiter is 318 times Earth's mass. Even though it's also larger (which reduces escape velocity), the mass effect dominates. Jupiter's escape velocity is 60 km/s - over 5 times Earth's.