• Question: What speed dose a rocket have to go in order to break though the atmosphere

    Asked by Willy wonka v2 on 3 Mar 2020.
    • Photo: Yuri Yushtein

      Yuri Yushtein answered on 3 Mar 2020:

      First cosmic velocity: orbital velocity, the velocity required to stay in orbit; Second cosmic velocity: Earth escape velocity, the velocity required to leave the Earth’s orbit to go to other planets in the Solar System; Third cosmic velocity: Solar System escape velocity, the velocity required to leave the Solar System to go to the stars …
      I would invite you to do a small internet research and find the actual velocities and how these are determined.

    • Photo: Andrew Ball

      Andrew Ball answered on 5 Mar 2020:

      Indeed as Yuri hints, the answer depends on whether you want to escape Earth’s gravity well completely (about 11.2km/s from the Earth’s surface, if I recall correctly) or just go into orbit above the Earth’s atmosphere (about 7km/s), or go up to just escape the atmosphere then fall back down again (the speed you need depends somewhat on aerodynamics).