Artists's Conception of Jupiter Icy Moons Orbiter

The Jupiter Icy Moons Orbiter (JIMO) was a proposed spacecraft designed to explore the icy moons of Jupiter. The main target was Europa, the suspected ocean of which is one of the places where very simple alien life is a possibility in our solar system. Ganymede and Callisto, which are now thought to have liquid, salty oceans beneath their icy surfaces, were also targets of interest for the probe. Download high resolution version (640x828, 63 KB)Jupiter Icy Moons Orbiter File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Download high resolution version (640x828, 63 KB)Jupiter Icy Moons Orbiter File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... A spacecraft is a vehicle, vessel, craft or device designed to operate beyond the surface of the Earth in outer space. ... Atmospheric characteristics Atmospheric pressure 70 kPa Hydrogen ~86% Helium ~14% Methane 0. ... Atmospheric characteristics Atmospheric pressure 1 µPa Oxygen 100% Europa redirects here. ... Atmospheric characteristics Atmospheric pressure trace Oxygen 100% Ganymede (gan-ə-meed, IPA: ; Greek Γανυμήδης) is Jupiters largest moon, and indeed the largest moon in the entire solar system; it is larger in diameter than Mercury but only about half its mass. ... Atmospheric characteristics Atmospheric pressure trace Carbon dioxide 100% Callisto (kə-lis-toe, IPA: ; Greek Καλλιστώ) is a moon of the planet Jupiter, discovered in 1610 by Galileo Galilei. ...

Due to a shift in priorities at NASA that favored manned space missions, the project lost funding in 2005, effectively cancelling the JIMO mission. Source. Engineers at the Jet Propulsion Laboratory connected with JIMO were laid off or reassigned during the spring and summer of that year. NASA logo Listen to this article · (info) This audio file was created from an article revision dated 2005-09-01, and does not reflect subsequent edits to the article. ...

The US president's 2006 budget request to Congress essentially cut funding for JIMO. Among other issues, the proposed nuclear technology was deemed too ambitious, as was the multiple-launch and in-orbit assembly mission architecture. NASA is instead considering a demonstration mission to a target closer to Earth to test out the reactor and heat rejection systems. The spacecraft would possibly be scaled down from its original size as well. The Congress of the United States is the legislative branch of the federal government of the United States of America. ... Earth (IPA: , often referred to as the Earth, Terra, or Planet Earth) is the third planet in the solar system in terms of distance from the Sun, and the fifth largest. ...

When it was cancelled, the JIMO mission was in its early planning stage and launch wasn't expected before 2017. It was to be the first proposed mission of NASA's Project Prometheus, a program for developing nuclear fission into a viable means of spacecraft propulsion. 2017 (MMXVII) will be a common year starting on Sunday of the Gregorian calendar. ... NASA logo Listen to this article · (info) This audio file was created from an article revision dated 2005-09-01, and does not reflect subsequent edits to the article. ... Nuclear reactors may be used to power ion engines such as this one used on Deep Space 1 Project Prometheus was established in 2003 by NASA to develop nuclear-powered systems for long-duration space missions. ... For the generation of electrical power by fission, see Nuclear power plant An induced nuclear fission event. ... A remote camera captures a close-up view of a Space Shuttle Main Engine during a test firing at the John C. Stennis Space Center in Hancock County, Mississippi Spacecraft propulsion is used to change the velocity of spacecraft and artificial satellites, or in short, to provide delta-v. ...

The JIMO spacecraft

JIMO was to have a large number of revolutionary features. Throughout its main voyage to the Jupiter moons, it was to be propelled by an ion propulsion called HiPEP, and powered by a small fission reactor. A Brayton power conversion system would convert reactor heat into electricity. Providing a thousand times the electrical output of conventional solar or RTG based power system, the reactor was expected to open up opportunities like flying a full scale ice-penetrating radar system and providing a strong, high-bandwidth data transmitter. An ion engine test An ion thruster is a type of spacecraft propulsion that uses beams of ions for propulsion. ... HiPEP Beam Extraction Test In 2003 NASA ground-tested a new version of their ion thruster called High Power Electric Propulsion, or HiPEP. Theory The HiPEP thruster differs from earlier ion thrusters because the xenon ions are produced using a combination of microwave and magnetic fields. ... Core of a small nuclear reactor used for research. ... The Brayton cycle is a cyclic process generally associated with the gas turbine. ... A solar cell, made from a monocrystalline silicon wafer A solar cell (or a photovoltaic cell) is a semiconductor device that converts photons from the sun (solar light) into electricity. ... // A radioisotope thermoelectric generator (RTG) is a simple electrical generator which obtains its power from radioactive decay. ... This long range RADAR antenna, known as ALTAIR, is used to detect and track space objects in conjunction with ABM testing at the Ronald Reagan Test Site on the Kwajalein atoll[1]. RADAR is a system that uses radio waves to detect, determine the direction and distance and/or speed... In general, data consist of propositions that reflect reality. ...

Using electric propulsion (8 ion engines, plus Hall thrusters of varying sizes) would make it possible to go into and leave orbits around Jupiter's moons, creating more thorough observation and mapping windows than exist for the current spacecraft, which must make short fly-by maneuvers because of limited fuel for maneuvering. 2 kW Laboratory Hall Thruster in operation at the Princeton Plasma Physics Laboratory A Hall effect thruster is a type of ion thruster in which the propellant is accelerated by an electric field in a plasma discharge with a radial magnetic field. ... Atmospheric characteristics Atmospheric pressure 70 kPa Hydrogen ~86% Helium ~14% Methane 0. ...

The design called for the reactor to be positioned in the tip of the spacecraft behind a strong radiation shield protecting sensitive spacecraft equipment. The reactor would only be powered up once the probe was well out of Earth orbit, so that the amount of radionuclides that must be launched into orbit is minimized. This configuration is thought to be less risky than the radioisotope thermoelectric generators (RTGs) used on previous missions to the outer solar system. RTGs contain large amounts of highly radioactive material which generate heat for the thermoelectric couples. Particle radiation is the radiation of energy by means of small fast-moving particles that have energy and mass. ... Earth (IPA: , often referred to as the Earth, Terra, or Planet Earth) is the third planet in the solar system in terms of distance from the Sun, and the fifth largest. ... A radionuclide is an atom with an unstable nucleus. ... // A radioisotope thermoelectric generator (RTG) is a simple electrical generator which obtains its power from radioactive decay. ... Major features of the Solar System (not to scale): The Sun, the eight planets, the asteroid belt containing the dwarf planet Ceres, outermost there is the dwarf planet Pluto (the dwarf planet Eris not shown), and a comet. ...

Northrop Grumman was selected on September 20, 2004 for a $400 million preliminary design contract, beating Lockheed Martin and Boeing IDS. The contract was to have run through to 2008. Separate contracts, covering construction and individual instruments, were to be awarded at a later date. The Northrop Grumman Corporation (NYSE: NOC) is an aerospace and defense conglomerate that is the result of a 1994 merger between Northrop and Grumman. ... September 20 is the 263rd day of the year (264th in leap years). ... 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ... Lockheed/BAE/Northrop F-35 Lockheed Trident missile C-130 Hercules; in production since the 1950s, now as the C-130J Lockheed Martin (NYSE: LMT) is an aerospace manufacturer formed in 1995 by the merger of Lockheed Corporation with Martin Marietta. ... Boeing Integrated Defense Systems (Boeing IDS), based in St. ... 2008 (MMVIII) will be a leap year starting on Tuesday of the Gregorian calendar. ...

Preliminary design specifications

• Science payload mass: 1500 kg
• Electric turboalternators: multiple 104 kW (440 V AC)
• Deployable radiator: 422 m² surface area
• Electric Herakles ion thrusters: multiple 30 kW high efficiency, specific impulse 7000 s (69 kN·s/kg)
• Hall thrusters: high power, higher thrust
• Telecommunications link: 10 Mbit/s (4×250 watt TWTA)
• Deployed size: 58.4 m long × 15.7 m wide
• Stowed size: 19.7 m long × 4.57 m wide
• Mission design life: 20 years
• Launch date: 2017
• Launch Vehicle: Delta 4H.

Source It has been suggested that some sections of this article be split into a new article entitled Delta IV launches. ...

External links

• Project Prometheus webpage at NASA
• Animation outlining the mission