A trajectory is the path that an object follows as it moves through space, usually under the influence of forces like gravity, thrust, or air resistance.
In simple terms: A trajectory is the curved or straight path an object takes while moving.
📚 Types of Trajectories
| Type of Trajectory | Description |
|---|---|
| Straight-line | When no external forces (like gravity or friction) act — the object moves in a straight path. |
| Parabolic | Common for projectiles — like a ball thrown in the air or a rocket escaping gravity. |
| Elliptical | The shape of most planetary or satellite orbits (e.g., Earth's orbit around the Sun). |
| Hyperbolic | When an object moves fast enough to escape a planet's gravity completely and leaves into deep space. |
🌍 Trajectory in Space Science
In space missions, trajectory calculations are critical:
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🚀 A rocket’s launch trajectory determines if it reaches orbit or not.
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🛰️ A satellite’s orbit trajectory controls how it circles the Earth.
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🌕 A moon or Mars mission requires precise interplanetary trajectory planning.
Even a small error in trajectory can lead to:
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Missing the target
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Crashing into a planet
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Being lost in space
🧠 How is a trajectory calculated?
Trajectories are calculated using:
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Newton’s laws of motion (force, mass, acceleration)
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Kepler’s laws (for orbits around celestial bodies)
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Gravity and velocity values at different points
🛠 Example:
If a spacecraft is launched from Earth to the Moon, its trajectory might look like this:
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Vertical lift-off
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Arched path leaving Earth’s atmosphere
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Curved elliptical path toward the Moon
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Adjusted trajectory for Moon orbit insertion
Each segment is carefully planned and executed — that full curved path is the trajectory.