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  2. Escape velocity - Wikipedia

    en.wikipedia.org/wiki/Escape_velocity

    In most situations it is impractical to achieve escape velocity almost instantly, because of the acceleration implied, and also because if there is an atmosphere, the hypersonic speeds involved (on Earth a speed of 11.2 km/s, or 40,320 km/h) would cause most objects to burn up due to aerodynamic heating or be torn apart by atmospheric drag. For ...

  3. Atmospheric escape - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_escape

    One classical thermal escape mechanism is Jeans escape, [1] named after British astronomer Sir James Jeans, who first described this process of atmospheric loss. [2] In a quantity of gas, the average velocity of any one molecule is measured by the gas's temperature, but the velocities of individual molecules change as they collide with one another, gaining and losing kinetic energy.

  4. Atmospheric entry - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_entry

    The five species model is only usable for entry from low Earth orbit where entry velocity is approximately 7.8 km/s (28,000 km/h; 17,000 mph). For lunar return entry of 11 km/s, [23] the shock layer contains a significant amount of ionized nitrogen and oxygen. The five-species model is no longer accurate and a twelve-species model must be used ...

  5. Parabolic trajectory - Wikipedia

    en.wikipedia.org/wiki/Parabolic_trajectory

    At any time the average speed from = is 1.5 times the current speed, i.e. 1.5 times the local escape velocity. To have t = 0 {\displaystyle t=0\!\,} at the surface, apply a time shift; for the Earth (and any other spherically symmetric body with the same average density) as central body this time shift is 6 minutes and 20 seconds; seven of ...

  6. Hohmann transfer orbit - Wikipedia

    en.wikipedia.org/wiki/Hohmann_transfer_orbit

    The column labeled "LEO height" gives the velocity needed (in a non-rotating frame of reference centered on the earth) when 300 km above the Earth's surface. This is obtained by adding to the specific kinetic energy the square of the escape velocity (10.9 km/s) from this height. The column "LEO" is simply the previous speed minus the LEO ...

  7. List of artificial objects leaving the Solar System - Wikipedia

    en.wikipedia.org/wiki/List_of_artificial_objects...

    In order to leave the Solar System, the probe needs to reach the local escape velocity. Escape velocity from the sun without the influence of Earth is 42.1 km/s. In order to reach this speed, it is highly advantageous to use as a boost the orbital speed of the Earth around the Sun, which is 29.78 km/s.

  8. Orbital mechanics - Wikipedia

    en.wikipedia.org/wiki/Orbital_mechanics

    To escape the Solar System from a location at a distance from the Sun equal to the distance Sun–Earth, but not close to the Earth, requires around 42 km/s velocity, but there will be "partial credit" for the Earth's orbital velocity for spacecraft launched from Earth, if their further acceleration (due to the propulsion system) carries them ...

  9. Specific orbital energy - Wikipedia

    en.wikipedia.org/wiki/Specific_orbital_energy

    The increase per meter would be 4.8 J/kg; this rate corresponds to one half of the local gravity of 9.5 m/s 2. The speed is 7.8 km/s, the net delta-v to reach this orbit is 8.0 km/s. Taking into account the rotation of the Earth, the delta-v is up to 0.46 km/s less (starting at the equator and going east) or more (if going west).