Jupiter is the fifth planet from the Sun and the largest planet in the solar system, with
a mass more than twice that of all the other planets combined.
Jupiter’s stripes and swirls are cold, windy clouds of ammonia and water floating in a
hydrogen and helium-rich atmosphere.
The pressure and temperature below the gaseous top layers rise to the point where hydrogen
atoms condense into a liquid.
Pressures rise to the point when hydrogen loses its electrons, allowing the soupy mess
to conduct electricity, just like metal.
Jupiter’s quick spin on its axis means that one day on the planet lasts less than 10 Earth
hours, sparking electrical currents that might fuel its intense and strong magnetic field,
which is 16 to 54 times stronger than Earth’s.
Something strange is happening beneath Jupiter’s ammonia-ice clouds.
While the Hubble Space Telescope can capture stunning views of Jupiter’s ever-changing
colorful belts and erupting massive storms such as the Great Red Spot, it can’t peer
behind the planet’s spinning ammonia ice clouds to discover what’s creating the turbulence.
This is when we enter radio astronomy, the study of the electromagnetic radiation emitted
by celestial bodies.
Radio telescopes collect data to produce images of things we wouldn’t normally be able to
view by using longer wavelengths of light that optical telescopes cannot detect.
Astronomers used data from the Atacama Large Millimeter/submillimeter Array (ALMA) in northern
Chile, as well as the Hubble Space Telescope, the Very Large Array, the Gemini, Keck and
Subaru observatories in Hawaii, and the Very Large Telescope (VLT) in Chile, to see what’s
going on beneath Jupiter’s clouds.
Data gathered by those telescopes after the January 2017 eruptions, which allowed them
to see 31 miles (50 kilometers) beneath Jupiter’s clouds, revealed that violent storm clouds
are disrupting Jupiter’s belts and even changing their color.
Thanks to ALMA, scientists were able to create a three-dimensional map of the distribution
of ammonia gas beneath the clouds.
And for the first time, they were able to analyze the atmosphere behind the ammonia
cloud layers following an intense eruption on Jupiter.
These powerful eruptions resemble thunderstorms on Earth, and they frequently involve lightning.
They appear as short, bright plumes on Jupiter’s visible cloud layer, but the researchers were
able to see deeper here.
The plumes were flowing from the planet’s South Equatorial Belt before colliding with
its intense winds, while four bright spots vanished from the planet’s North Equatorial
Belt, which then enlarged and changed color.
The analysis of the plumes backs up the theory that they originate around 80 kilometers beneath
the clouds, in a zone ruled by clouds of liquid water.
The radio wave images obtained from ALMA and other telescopes show high concentrations
of ammonia gas.
The observations match one current hypothesis about how the white plumes form; they’re
triggered by moist convection currents at the base of water clouds deeper inside Jupiter’s
atmosphere.
These eruptions appear to be sufficient to push ammonia gas above the main cloud deck
to the tropopause, the coldest portion of the atmosphere, where it spreads out like
lightning and thunder-laden cumulonimbus clouds on Earth, creating visible white plumes as
it freezes.
If these plumes continue to be active and undergo convective episodes, they may eventually
disrupt one of these complete bands, albeit it may take a few months.
Researchers followed up the radio wave images after an amateur Australian astronomer observed
a disruptive plume on Jupiter’s visible cloud belt.
They compared ALMA radio wave images to Hubble telescope and mid-infrared range images taken
over the same period.
It’s a great example of the amateur astronomy community and scientists from many observatories
and agencies working together to create something truly unique, another stunning glimpse at
our solar system’s largest planet.
Radio astronomy is so difficult at Jupiter because Jupiter’s rotation once every 10
hours usually blurs radio maps because these maps take many hours to observe.
Scientists used special computer software to analyze the ALMA data to obtain radio maps
of the surface to compare with the visible UV light images taken by Hubble.