This image of Jupiter's white ovals BC and DE was taken by the Galileo spacecraft

Birth of the Classic White Ovals of Jupiter

There are other white ovals in the atmosphere of Jupiter, but the birth of the three classic ovals happened in the following way.

The South Temperate Zone (STZ) of Jupiter is located between -27 and -37 degrees south latitude, near the Great Red Spot (located at -22 degrees). In 1939 the STZ underwent some sort of disturbance called the "South Temperatue Zone Disturbance". Three dark hazy cloud features appeared and divided the STZ into columnar sections. An observer, E.J. Reese, called the dark bands AB, CD, and EF. As the disturbance continued it became evident that the light areas between the dark bands were taking on the shape of broad, elongated ovals. Air in the ovals was circulating in the counter-clockwise direction. Scientists called these ovals between the dark areas FA, BC, and DE.

Over time the ovals have drastically changed their appearance . They were initially very long and stretched. Time has shown them to both shrink in size and gradually fade in appearance. FA has virtually disappeared from sight, and can only be seen in certain types of lighting.

Despite many years of jostling each other in the STZ, in 1998, BC and DE merged into a single oval called BE. With time BE will probably fade away, just as FA has done.

Return to Jupiter's Clouds

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Jupiter's Belts and Zones

The striped cloud bands on Jupiter are certainly not as straight as they appear to be in this picture! The picture shows that the striped pattern is divided into belts and zones, which are labeled. In...more

An Overview of the Evolution of Jupiter's Atmosphere

Atmospheres of the giant planets have definetely evolved from their formation out of the primitive solar nebula. How much they have evolved remains to be seen, however. Because of their enormous gravity,...more

Jupiter's Mesosphere

The mesosphere of Jupiter is a region of balance between warming and cooling. That essentially means that nothing happens there. Except for diffusion, the atmosphere is still. Upper reaches of the atmosphere,...more

An Overview of Jupiter's Atmospheric Structure

As on Earth, the atmosphere of Jupiter consists of a troposphere, stratosphere, mesosphere, and thermosphere. The troposphere is the region where the visible clouds are to be found. The stratosphere, as...more

Jupiter's Stratosphere

The stratosphere of Jupiter is a region of warming as determined by infrared measurements of methane (CH4) in the region. Like the troposphere, the stratosphere is warmed by the sun, warmed by Jupiter's...more

Jupiter's Troposphere

The troposphere of Jupiter is where the clouds are. Clouds form in regions of strong atmospheric motion, when condensation takes place. The troposphere is the region rapidly stirred by vertical motions....more

Altitude Variations of the Belts & Zones

On Jupiter, the winds in the belts and zones blow first in one direction, then in the opposite direction. Wind blows east in a belt, and west in a zone. The clouds rise up in a belt, and drop down in a...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA