Plasma Wave Subsystem

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This diagram shows how the PWS and PRA share the Voyager antenna, and its overall location on the Voyager-type design Voyager-pws.gif
This diagram shows how the PWS and PRA share the Voyager antenna, and its overall location on the Voyager-type design
Here the data recorded by the PWS on Voyager 1 is converted to audio

Plasma Wave Subsystem (sometimes called Plasma Wave System), abbreviated PWS, is an instrument that is on board the Voyager 1 and Voyager 2 unmanned probes of the Voyager program. The device is 16 channel step frequency receiver and a low-frequency waveform receiver that can measure electron density. [1] The PWS uses the two long antenna in a V-shape on the spacecraft, which are also used by another instrument on the spacecraft. [2] The instrument recorded data about the Solar System's gas giants, and about the outer reaches of the Heliosphere, and beyond. [3] In the 2010s, the PWS was used to play the "sounds of interstellar space" as the spacecraft can sample the local interstellar medium after they departed the Sun's heliosphere. [3] The heliosphere is a region essentially under the influence of the Sun's solar wind, rather than the local interstellar environment, and is another way of understanding the Solar System in comparison to the objects gravitationally bound (e.g in orbit) around Earth's Sun.

Contents

The PWS instrument plan was introduced in 1974 during the development of the Voyager program. [4] It was hoped it would help increase understanding of wave particle interactions and record data on the magnetospheres of planets like Jupiter and Saturn. [4] The instruments went on to record radio waves at Jupiter, Saturn, Uranus, and Neptune. [3]

The PWS instrument is one of the instruments that is a part of the Voyager interstellar mission, and they have operated for several decades after their 1977 launch into the 2010s. [5]

Specifications

List: [6]

PWS and PRS

PLS, another Plasma instrument, and PWS antenna are noted in this diagram. Note that the antenna are truncated in this diagram and are much longer than shown, extending out 10 meters. The PWS also needs electrical power to operate, which comes from the RTG (also on this diagram). Voyager spacecraft structurePWSred.jpg
PLS, another Plasma instrument, and PWS antenna are noted in this diagram. Note that the antenna are truncated in this diagram and are much longer than shown, extending out 10 meters. The PWS also needs electrical power to operate, which comes from the RTG (also on this diagram).

See also

Related Research Articles

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<span class="mw-page-title-main">Voyager program</span> Ongoing NASA program

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<span class="mw-page-title-main">Heliosphere</span> Region of space dominated by the Sun

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<span class="mw-page-title-main">Solar Orbiter</span> European space-based solar observatory

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<span class="mw-page-title-main">Interstellar probe</span> Space probe that can travel out of the Solar System

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Magnetometer (<i>Juno</i>) Scientific instrument on the Juno space probe

Magnetometer (MAG) is an instrument suite on the Juno orbiter for planet Jupiter. The MAG instrument includes both the Fluxgate Magnetometer (FGM) and Advanced Stellar Compass (ASC) instruments. There two sets of MAG instrument suites, and they are both positioned on the far end of three solar panel array booms. Each MAG instrument suite observes the same swath of Jupiter, and by having two sets of instruments, determining what signal is from the planet and what is from spacecraft is supported. Avoiding signals from the spacecraft is another reason MAG is placed at the end of the solar panel boom, about 10 m and 12 m away from the central body of the Juno spacecraft.

Microwave Radiometer (<i>Juno</i>)

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References

  1. "NASA - NSSDCA - Experiment - Details". nssdc.gsfc.nasa.gov. Retrieved 2019-09-20.
  2. "Voyager - Spacecraft - Planetary Radio Astronomy (PRA) and Plasma Wave Subsystem (PWS)". voyager.jpl.nasa.gov. Retrieved 2019-09-20.
  3. 1 2 3 Adler, Doug (July 2, 2018). "Forty years and still going strong". Astronomy.com. Retrieved 2019-09-20.
  4. 1 2 3 "A Plasma Wave Investigation for the Voyager Mission". www-pw.physics.uiowa.edu. Retrieved 2019-09-20.
  5. "Voyager - Fast Facts". voyager.jpl.nasa.gov. Retrieved 2019-09-20.
  6. "NASA - NSSDCA - Experiment - Details".
  7. "Voyager - Spacecraft - Planetary Radio Astronomy (PRA) and Plasma Wave Subsystem (PWS)". voyager.jpl.nasa.gov. Retrieved 2019-09-20.
  8. "Voyager - Spacecraft - Planetary Radio Astronomy (PRA) and Plasma Wave Subsystem (PWS)". voyager.jpl.nasa.gov. Retrieved 2019-09-20.