Since 2016, the Juno spacecraft has been collecting data on the Gas Giant’s interior and the latest findings are on “hot spots” of the planet’s atmosphere.
It’s been 25 years since NASA sent history’s first probe—called Galileo— into Jupiter, the largest planet of the solar system. During Galileo’s descent, scientists weren’t expecting to find out that the planet was hotter and denser. With new data on NASA’s Juno probe, it suggests that Jupiter’s “hot spots” are deeper and wider than anticipated to a great degree.
The information was revealed, along with an update on Jupiter’s polar cyclone, during a virtual media briefing at the fall conference of the American Geophysical Union in 2020.
According to the principal investigator of Juno at the Southwest Research Institute in San Antonio, Scott Bolton, the giant planets don’t have a solid or liquid base like Earth but have deep atmospheres. He added that to better understand the things that are happening deep into one of those worlds, looking below the cloud layer must be done, and Juno just did that after its 29th close-up science pass of the Gas Giant. The information gathered has shed new light on the old mysteries of the planet. However, it also poses new ones.
The old mystery is a reference to the information that the space probe Galileo had beamed back to Earth on December 7, 1995, with 57 minutes and 36 seconds worth of data—significant scientific investments of the past. When the interpreted information gathered from Galileo ascertained them that the planet’s surroundings were dry and windy, scientist attributed the finding to the fact that the 34-kilogram probe had descended into the atmosphere within one of the planet’s relatively rare hot spots, localized atmospheric “deserts” that span across Jupiter’s northern equatorial region.
However, Juno space probe’s data from its microwave instrument indicated that the whole equatorial belt, which is a brown, broad, cyclonic band that wraps around the planet just above Jupiter’s equator, is generally a very dry region. The conclusion can be drawn that the hot spots might not be isolated “deserts” but rather windows into the planet’s vast regions of the atmosphere that may be drier and hotter than other areas—which was discovered, credits to Juno.
With Juno’s high-resolution data, it showed that the Jovian hot spots are associated with breaks in Jupiter’s cloud deck, providing a glimpse into the planet’s deep atmosphere. In addition, the data also showed the hot spots, flanked by active storms and clouds, are fueling high-altitude electrical discharges known as “shallow lightning,” which was a recent discovery of the Juno space probe. In the cold upper reaches of the Gas Giant’s atmosphere, water mixes with ammonia—it was a huge piece of the puzzle.
Tristan Guillot, co-investigator of Juno at the Universite Cote d’Azur in Nice, France, said that ammonia and water are combined in the up in the atmosphere of the planet, where “shallow lightning” is seen, become invisible to the space probe’s microwave instrument. The “mushballs” get heavy and fall deep into the atmosphere and create a large region that is depleted of both water and ammonia. When the “mushballs” melt and evaporate, the water and ammonia change back to a gaseous state and become visible to Juno again.
Another mystery that the giant-gas orbiter has revealed for the first time was the birth of auroral dawn storms—unique and spectacular aurorae of Jupiter, which is an early morning brightening in the planet. These transient and immense displays of light occur at the Jovian poles, which were also previously observed only by the Earth-orbiting—notably by Hubble Space Telescope—and ground-based observatories.
The dawn storms were first discovered in 1994 by Hubble’s Faint Object Camera. These storms consist of short-lived but broadening and brightening of the planet’s main auroral oval, an oblong-shaped curtain of light that surrounds both poles, near the site where the atmosphere emerges from the darkness in the early morning region. Before the space probe’s service, side views of the Jovian ultraviolet aurora were only seen, concealing everything to a certain degree what happens on the nightside of the planet.
Recent Comments