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| Our opinion on new NASA project on
the study of atmosphere and crust of Jupiter
S. B. Karavashkin and O.N. Karavashkina Special Laboratory for Fundamental Elaboration SELF 187 apt., 38 bldg., Prospect Gagarina, Kharkov, 61140, Ukraine phone +38 (057) 7370624; e-mail: selftrans@yandex.ru , selflab@mail.ru http://selftrans.narod.ru/SELFlab/index.html http://selftrans.narod.ru/index.html
Few days ago we received a press-release from NASA Jet Propulsion Laboratory (see below). It informs that NASA confirmed a new mission to Jupiter to study the atmosphere, magnetosphere and icy crust at the pole. Taking into account a very expensive project, experience of previous missions that tried to penetrate into hot dense layers of Jovian atmosphere, as well as our calculations of thermodynamic state of planets at the evolution level that Jupiter has today, we think, it is our moral duty to warn the authors of this project of some features which it would be desirable to note in preparation and realisation of this project. 1. On one hand, we fully agree with the authors of project, the study of Jovian atmosphere will be most efficient and informative near the poles, where the thermal gradient is lower and the atmosphere is more transparent. But in the pole area this mission will find neither overcooled hydrogen ocean nor some kind of ice. The landing probe will have a resource for 4- 6 hundred thousand kilometres of the atmosphere's depth, dependently on the insulation of shell and devices. 2. Noting the said in the item 1, the landing probe will descend through the high-gradient thermal field. This means, effective thermal protection will be necessary. Possibly, it would be a good plan to use vapouring materials. Just this and the speed of descent will provide the depth of penetration into the atmosphere. 3. When designing the landing probe, the engineers should also account highly aggressive medium and active electric charges typical for all height of atmosphere, especially at upper layers. At the poles, additionally, the strength of electric field and auroras will appear even higher than elsewhere on Jupiter and multiply stronger than those terrestrial, which can block the transmission of information and work of other devices. The probe has to be ready to encounter it. It especially concerns the transmission antennas and remote transducers which are most vulnerable for chemical and electric aggression. 4. Transducers have to be ready to work at the temperature about 2- 3 thousand of degrees and hundreds terrestrial atmospheres of pressure. This especially concerns the specimen intake chambers and optical devices. 5. Even if the landing probe were happy to penetrate deep, the utmost what it will be able to find will be the protoplanet at the stage of fragmental crust formation (at the poles, most probably, already stable, but still very hot). With it, the drill will only add weight to the landing probe. 6. The optical devices also have to be ready to work under complex hard conditions. In particular, they have to be able to work at infrared range, as the higher-frequency radiation will be too weak there. Although we cannot exclude, at the present stage of Jovian evolution, there can be lack of so-so transparent layer of atmosphere under outer layers. With all these stipulations, we absolutely agree, this mission is extremely important to study the physical features of other planets evolution. The above considerations are targeted to promote the maximally effective mission with minimum of unexpected cases that naturally will take place, if the researchers expect the icy crust on Jupiter. >>>>>>>>>>>>>>>>>>>>>>>>>>>> Carolina Martinez (818) 354-9382Jet Propulsion Laboratory, Pasadena, Calif. Dolores Beasley/Erica Hupp (202) 358-1753/1237 NASA Headquarters, Washington Press Release: 2005-090 June 1, 2005 NASA Selects New Frontiers Mission Concept Study NASA today announced that a mission to fly to Jupiter will proceed to a preliminary design phase. The mission is called Juno, and it is the second in NASA's New Frontiers Program.The mission will conduct an in-depth study of the giant planet. The mission proposes to place a spacecraft in a polar orbit around Jupiter to investigate the existence of an ice-rock core; determine the amount of global water and ammonia present in the atmosphere; study convection and deep wind profiles in the atmosphere; investigate the origin of the jovian magnetic field; and explore the polar magnetosphere. "We are excited at the prospect of the new scientific understanding and discoveries by Juno in our continued exploration of the outer reaches of our solar system during the next decade," said Dr. Ghassem Asrar, deputy associate administrator for NASA's Science Mission Directorate. At the end of the preliminary design study, the mission must pass a confirmation review that will address significant schedule, technical and cost risks before being confirmed for the development phase. Dr. Scott Bolton of Southwest Research Institute, Boulder, Colo., is the principal investigator. NASA's Jet Propulsion Laboratory, Pasadena, Calif., will provide mission project management. Lockheed Martin Space Systems, Denver, will build the spacecraft. NASA selected two proposed mission concepts for study in July 2004 from seven submitted in February 2004 in response to an agency Announcement of Opportunity. "This was a very tough decision given the exciting and innovative nature of the two missions," Asrar added. The selected New Frontiers science mission must be ready for launch no later than June 30, 2010, within a mission cost cap of $700 million. The New Frontiers Program is designed to provide opportunities to conduct several of the medium-class missions identified as top priority objectives in the Decadal Solar System Exploration Survey, conducted by the Space Studies Board of the National Research Council. The first NASA New Frontiers mission will fly by the Pluto-Charon system in 2014 and then target another Kuiper asteroid belt object. 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