Controlling descent of a zero pressure balloon

A system for controlling balloon descent,

• comprising:
• a balloon structure having a first balloon envelope;
• and
• an apparatus attached to the balloon structure, the apparatus comprising:
• a solenoid chamber having a plunger configured to create an opening in the first balloon envelope when the solenoid chamber is actuated, the opening enabling gas to evacuate from the first balloon envelope;
• a mixer valve having a nozzle coupled to the solenoid chamber, the mixer valve configured to create a gas mixture formed from the gas evacuating from the opening in the first balloon envelope and atmospheric gas;
• a heating device attached to the nozzle, the heating device configured to heat the gas mixture created by the mixer valve;
• and
• a second balloon envelope attached to the nozzle, the second balloon envelope arranged to expand in proportion to a quantity of the heated gas mixture passing through the nozzle, wherein the expansion of the second balloon envelope creates an amount of lift for controlling descent of the balloon structure.