Portal:Jupiter/Radiation astronomy/6

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Microwaves[edit | edit source]

A radio image of Jupiter from the VLA at three wavelengths: 2 cm in blue, 3 cm in gold, and 6 cm in red. Credit: Imke de Pater, Michael H. Wong (UC Berkeley), Robert J. Sault (Univ. Melbourne).

"We in essence created a three-dimensional picture of ammonia gas in Jupiter’s atmosphere, which reveals upward and downward motions within the turbulent atmosphere."[1]

"The radio map shows ammonia-rich gases rising into and forming the upper cloud layers: an ammonium hydrosulfide cloud at a temperature near 200 Kelvin (minus 100 degrees Fahrenheit) and an ammonia-ice cloud in the approximately 160 Kelvin cold air (minus 170 degrees Fahrenheit). These clouds are easily seen from Earth by optical telescopes."[2]

"Conversely, the radio maps show ammonia-poor air sinking into the planet, similar to how dry air descends from above the cloud layers on Earth."[2]

"The map also shows that hotspots – so-called because they appear bright in radio and thermal infrared images – are ammonia-poor regions that encircle the planet like a belt just north of the equator. Between these hotspots are ammonia-rich upwellings that bring ammonia from deeper in the planet."[2]

"With radio, we can peer through the clouds and see that those hotspots are interleaved with plumes of ammonia rising from deep in the planet, tracing the vertical undulations of an equatorial wave system."[3]

"We now see high ammonia levels like those detected by Galileo from over 100 kilometers deep, where the pressure is about eight times Earth’s atmospheric pressure, all the way up to the cloud condensation levels."[1]

"We now see fine structure in the 12 to 18 gigahertz band, much like we see in the visible, especially near the Great Red Spot, where we see a lot of little curly features. Those trace really complex upwelling and downwelling motions there."[3]

"Jupiter’s rotation once every 10 hours usually blurs radio maps, because these maps take many hours to observe. But we have developed a technique to prevent this and so avoid confusing together the upwelling and downwelling ammonia flows, which had led to the earlier underestimate."[4]

"The pink glow surrounding the planet [in the image on the right] is synchrotron radiation produced by spiraling electrons trapped in Jupiter’s magnetic field. Banded details on the planet’s disk probe depths of 30-90 km below the clouds. This image is averaged from 10 hours of VLA data, so the fine details seen in the other maps are smeared here by the planet’s rotation."[1]

References[edit | edit source]

  1. 1.0 1.1 1.2 Imke de Pater (2 June 2016). New radio map of Jupiter reveals what’s beneath colorful clouds. Berkeley, Calfornia USA: University of California, Berkeley. http://news.berkeley.edu/2016/06/02/new-radio-map-of-jupiter-reveals-whats-beneath-colorful-clouds/. Retrieved 18 August 2016. 
  2. 2.0 2.1 2.2 Robert Sanders (2 June 2016). New radio map of Jupiter reveals what’s beneath colorful clouds. Berkeley, Calfornia USA: University of California, Berkeley. http://news.berkeley.edu/2016/06/02/new-radio-map-of-jupiter-reveals-whats-beneath-colorful-clouds/. Retrieved 18 August 2016. 
  3. 3.0 3.1 Michael Wong (2 June 2016). New radio map of Jupiter reveals what’s beneath colorful clouds. Berkeley, Calfornia USA: University of California, Berkeley. http://news.berkeley.edu/2016/06/02/new-radio-map-of-jupiter-reveals-whats-beneath-colorful-clouds/. Retrieved 18 August 2016. 
  4. Robert Sault (2 June 2016). New radio map of Jupiter reveals what’s beneath colorful clouds. Berkeley, Calfornia USA: University of California, Berkeley. http://news.berkeley.edu/2016/06/02/new-radio-map-of-jupiter-reveals-whats-beneath-colorful-clouds/. Retrieved 18 August 2016.