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Pre-Launch


On August 5th, 2011 one of the world's most powerful rockets took off.

  • LIGHTNING TOWERS

    The four white spires that surround Juno’s launch pad are lightning towers, protecting the spacecraft from lightning strikes.


    Lightning Towers




    Surrounding the launch pad at Cape Canaveral are four lightning towers, each more than 300 feet tall. Given that Central Florida is one of the most active regions in the world when it comes to lightning strikes, NASA has always built lightning towers around launch pads. Grounded wires direct any lightning strikes harmlessly into the ground.
  • A COSMIC EVENT

    Launching Juno into space takes everything we know.


    A Cosmic Event

  • MASS BUDGET

    The Atlas V 551 rocket has a certain mass limit, and the margin for error is slim.


    Mass Budget

    A rocket like the Atlas V 551 can only carry so much mass into space. As engineers plan the mission, they have to follow a tight budget for the spacecraft’s load, which includes propellant, science instruments, and communication antennas.    
  • LAUNCH OVERVIEW

    Check out the key stages of the launch.


    Launch Overview

  • READY TO FLY

    Is Juno prepared for the journey ahead? Pre-launch tests trick the spacecraft into thinking it’s in space.


    Ready to Fly

  • WHEN DO WE DEPART?

    Juno has to launch within a tight window in time to reach Jupiter on schedule.


    When do we depart?

    To get to Jupiter, Juno has to launch when the planets are aligned properly, which happens only between August 5th and August 26th. If Juno misses this period, it has to wait another 13 months for the planets to align again. Each day during these three weeks there’s a launch window of only a few hours around noon Eastern Time.    
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Launch