Fastest Ways of Travel Through Space

Gravity Assist/Slingshot

• Definition:
  • A spaceflight maneuver where a spacecraft uses the gravitational influence of a planet or moon to change its speed and/or direction.
  • In simpler terms: A spacecraft uses a planet or moon's gravitational force to change its own direction or speed.
• How it Works:
  • Utilizes the planet's movement and gravity to "slingshot" the spacecraft.
  • Increases the spacecraft's speed and alters its orbital path.
• Benefits:
  • Conserves fuel.
  • Enables reaching destinations that would otherwise be unreachable.
• Examples of Spacecraft:
  • Voyager 2: Famous for using gravity assist to visit Jupiter, Saturn, Uranus, and Neptune in the late 1970s and 1980s. It is the most commonly used gravity assist laceration.
  • Cassini: Used gravity assists at Venus (twice), Earth (once), and Jupiter (once) to reach Saturn.
  • Messenger: Used assists at Earth, Venus, and Mercury (three times) to slow down enough to be captured by Mercury.

Ion Engines

• How They Work:
  • Extract ions from atoms and expel them from the engine at very high speeds (20 to 50 kilometers per second).
  • The large number of ions provides a long-lasting fuel source.
  • The engine provides continuous acceleration, gradually increasing speed over time.
  • Capable of reaching approximately 1% of the speed of light.
• Pros:
  • Can achieve speeds of around 7,000,000 miles per hour.
  • Fuel is used slowly.
  • Relatively lightweight.
  • Can escape Earth's orbit using a different fuel source and then use the ion engine for continuous propulsion.
• Cons:
  • Needs to be used continuously to be effective; stopping the engine causes deceleration.
  • Starts very slowly, unlike combustion engines.
  • Requires a significant amount of energy.

Solar Sails

• What are Solar Sails?
  • Absorbs light and converts it into movement to propel spacecrafts.
  • Speeds up spacecraft and helps them reach destinations faster.
  • Utilizes the momentum of photons from the sun.
  • Mirrors reflect the sun onto a spacecraft, increasing its speed.
• Examples of Spacecraft:
  • Japanese Space Exploration Agency, IKAROS.
  • LightSail 1.
  • LightSail 2.
• Pros:
  • Low cost, allowing for multiple sails to be used, increasing spacecraft movement.
  • Long lifespan.
  • Few moving parts.
  • Does not require propellant consumption.
  • Very light.
  • Minimal payload consumption.
• Cons:
  • Requires high-powered lasers and/or large sails.
  • Potential difficulties in controlling motion.
  • Challenges related to the durability and development of large, thin sails in the harsh space environment.

Choice Between Ion Engines and Solar Sails

• Slingshot is primarily for direction, not propulsion.
• Ion Engines vs. Solar Sails:
  • Ion engines are preferred over solar sails due to the difficulty in controlling solar sails and the large amount of space they occupy.
  • Solar sails may achieve high speeds, but are not efficient at continuous acceleration.
  • Ion engines provide continuous acceleration and have a longer-lasting fuel source.
  • Even though solar sails may be going incredibly incredibly fast (a few percent of the speed of light) once they get out of our solar system, they're not really gonna increase at all.
  • The thing with ion engines is that they're constantly increasing, and it's a lot longer fuel source.