The Juno spacecraft is designed to orbit Jupiter for a year and during this period, many measurements will be made to deepen our understanding of the nature of the planet
In June 2010, a new spacecraft named Juno will be launched towards Jupiter. When it reaches the star, it will enter a polar orbit around it and high enough to prevent it from being harmed by the star's radiation, a lesson learned from the experience of the Galileo spacecraft. The spacecraft is designed to orbit Jupiter for a year and during this period, many measurements will be made to deepen our understanding of the nature of the star. The intention is to study its magnetic field, its atmosphere and its rocky core, to measure convection currents in the atmosphere at greater depths than those visible parts, to measure the amount of water, ammonia and methane in the atmosphere, temperatures and wind speeds in its various layers (1).
In order to give a more comprehensive picture of Jupiter, another means of making measurements from the atmosphere itself must be used. The first to take this route were the Russians when they equipped two spaceships that had the planet Venus in balloons each. These spacecraft were Vega 1 and Vega 2 designed to land on the planet's surface. After the spacecraft entered the atmosphere in June 1985, the balloons were released and valuable information about the atmosphere of Venus was broadcast to Israel. Each balloon was made of Teflon and had a diameter of 3 meters. From the bottom of each ball there was a 54 meter long cable and attached to the bottom was a 13 meter long gondola containing all the scientific equipment. The weight of the gondola is 1.2 kg (21).
The limitations of a hot air balloon are twofold. It drifts with the wind and there is no way to control the direction of its movement and the duration of its activity depends on the lifespan of the batteries. In preparation for the launch of the Juno spacecraft, it is necessary to switch to a different configuration, to the configuration of an airship like the zeppelins that operated at the beginning of the 20th century. The airship will be inside a case that will detach from the spacecraft when it approaches Jupiter, enter the atmosphere and then open a parachute, following which the airship will open.
The airship will be made of light material like that of the Russian balloons. How will it be built? The direction to be followed is that of an internal skeleton made of light materials. This skeleton consists of a core of telescopic arms that extend in all directions and slowly unfold the ship's shell. The first airships were filled with hydrogen and then switched to helium for safety reasons. These gases are abundant in Jupiter's atmosphere. In the core of the ship there will be battery power cells that will operate an air pump that will draw in the gases from the atmosphere at the same time as the ship expands to its full size.
At the bottom of the airship will be a gondola with research equipment including cameras on all sides in order to achieve full visual coverage. It would be useful to place cameras on the upper side of the ship as well. Controlling the direction of the ship's movement will be done by exhausting and pumping air while folding and retrieving the telescopic skeleton and by means of wings on the rear side.
The ship will have two sources of power. One power source is batteries. A second source is the winds that blow in the atmosphere. The winds blow non-stop and speed reaches hundreds of kilometers per hour. It is worth thinking about a miniature wind turbine that can be used to provide the airship with power and in this way give it a very long lifespan.
Since Jupiter revolves around itself once every 10 hours, the communication disconnection from the airship will be 5 hours, a very short time. The information collected during these hours will be stored in the airship's computer memory and will be transmitted to Earth when eye contact is made with you or via the spacecraft.
A practical way to test such an airship is to build models that will be released from high-altitude aircraft or from satellites orbiting the Earth. The development and production of such an airship is quite a challenge since it is a new tool for the investigation of planets with an atmospheric presence. With the aim of encouraging the space industry in Israel, there is no reason for the State of Israel not to join the Juno project and the development of this ship will be done in Israel.
Sources
1. Clark S. - "NASA'S newest mission: orbiting the king of planets".
http://www. spaceflightnow. com/news/n0506/05juno
2. Kremnev RS et al-"VEGA balloon system and instrumentation" Science vol. 231 p 1408-1411 March 21, 1986
