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"Simulation of What Juno Will 'See' From Jupiter Orbit
This animation shows how Jupiter will appear to the camera onboard NASA's Juno mission, called JunoCam, as the spacecraft goes through an orbit."
also see: Juno Jupiter Orbiter: Unlocking Jupiter's Mysteries
http://www.youtube.com/watch?v=fz2DApsHay4
from "AN OVERVIEW OF THE JUNO MISSION TO JUPITER"
http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/40581/1/06-1103.pdf
Juno launches in August 2011 on an Atlas V 551 launch vehicle. The nominal cruise time to Jupiter is approximately 5.2 years. The trajectory requires a large deep-space maneuver about one year after launch and an Earth flyby about 26 months after launch, to acquire the additional energy to reach Jupiter.
Upon reaching Jupiter, the spacecraft executes a very long burn of its main engine for Jupiter Orbit Insertion (JOI) and a smaller JOI clean-up burn to achieve the 11-day polar orbit desired for the nominal science mission at Jupiter.
The 11-day orbit is characterized by a perijove of 1.06 RJ and an apojove
(furthest point from Jupiter) of about 39 RJ. This orbit optimizes the viewing
geometry for the science mission while avoiding the bulk of the Jovian radiation field. The altitude at perijove ranges between 4200 km and 5200 km.
The nominal mission is scheduled for thirty-two 11-day orbits or for about one
Earth year. The first two orbits are used for JOI and clean up, and the last 30 orbits are used for science acquisition. Upon completion of the last science orbit, Juno will deorbit and enter Jupiter for disposal.
The primary acquisition of science data occurs at ± 3 hours around perijove.
Outside of this window, operations are mainly focused upon navigation and
maneuvers to adjust the orbit, and upon transmission of engineering telemetry and science data from the just-completed perijove science.
There are two basic science modes for the science orbits: radiometer passes and gravity-science passes (Figure 12). During radiometer sciences passes, the MWR instrument is on, the gravity science payload elements are off, and the rest of the payload elements are on. The MWR measurements are taken with the solar array plane of the spinning spacecraft passing through the center of Jupiter and the radiometer antennas aligned with nadir. During gravity science passes, the MWR is powered down, the gravityscience payload instruments and the remaining payload elements are powered on, and the high-gain antenna is pointed toward the earth.
The Juno spacecraft is designed to spin, simplifying science operations once it is in orbit about Jupiter. Lockheed Martin Corporation is responsible for the design and build of the spacecraft, as well as for the integration of the payload elements. The polar-orbit design allows the spacecraft to be illuminated by the sun for virtually the entire mission, thereby enabling a solarpowered spacecraft.
Most of the spacecraft subsystems contain a high degree of inheritance from
previous robotic spacecraft missions, and the overall spacecraft design and implementation takes maximum advantage of this inheritance.
The spacecraft has three large solar arrays, which provide about 40 m2 of solar-cell area. One of the arrays is modified to hold a boom for the magnetometer experiment but sized such that the spacecraft stability is not compromised. A 2.5-m high-gain antenna provides X- and Ka-band communications and gravity science; it is gimbaled to provide the accurate pointing required during gravity science passes at Jupiter.
The spacecraft is primarily designed and built around the electronics radiation vault, which protects the heritage spacecraft and instrument electronics. The spacecraft uses a monopropulsion system and a bipropulsion system for attitude control maneuvers and larger deep-space and JOI maneuvers respectively. The instruments are placed on the upper deck, lower deck and solar-array booms...
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