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THE MISSION

Interstellar Science

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Interstellar Mission.  › larger image
SCIENCE INVESTIGATIONS
Magnetic field investigation (MAG)
Low energy charged particle investigation (LECP)
Plasma investigation (PLS)
Cosmic ray investigation (CRS)
Plasma wave investigation (PWS)

There are currently five science investigation teams participating in the VIM. The science teams for these investigations are currently collecting and evaluating data on the strength and orientation of the Sun's magnetic field; the composition, direction and energy spectra of the solar wind particles and interstellar cosmic rays; the strength of radio emissions that are thought to be originating at the heliopause, beyond which is interstellar space; and the distribution of hydrogen within the outer heliosphere.

 

There are six operating instruments on-board each Voyager spacecraft.  These instruments directly support the five science investigation teams. In addition, data is being collected from the Ultraviolet Spectrometer Subsystem (UVS). While there are no science investigation teams associated with this instrument, the captured data is made available to interested scientists.

Science Data Acquisition Strategy

Science data are returned to earth in real time at 160 bps. Real time data capture uses 34 meter Deep Space Network (DSN) resources with the project goal to acquire at least 16 hours per day of real time data per spacecraft. This goal is not always achieved due to the competition for DSN resources with prime mission projects and other extended mission projects.

 

Once a week per spacecraft, 48 seconds of high rate (115.2 kbps) PWS data are recorded onto the Digital Tape Recorder (DTR) for later playback.  An additional 48 seconds are recorded each week on Voyager 1.  These data are played back to Earth once every 6 months per spacecraft and require 70 meter DSN support for data capture. After transmission of the data (either real time or recorded) to JPL, it is processed and made available in electronic files to the science teams located around the country for their processing and analysis.