A New Red Spot on Jupiter - HubbleSite

Taken from: Hubble 2008: Science Year in Review

Produced by NASA Goddard Space Flight Center and the Space Telescope Science Institute.

The full contents of this book include more Hubble science articles, an overview of the telescope, and more. The complete volume and its component sections are available for download online at:

www.hubblesite.org/hubble_discoveries/science_year_in_review

National Aeronautics and Space Administration

A New Red Spot on Jupiter

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Hubble 2008: science Year in review

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On May 9 and 10, Hubble took this image, which revealed a new red spot on Jupiter (left-most spot). The Great Red Spot, larger than two Earths, can be seen to the right.

A New Red Spot on Jupiter

Since the mid-1600s, astronomers have marveled at changing spots and bands seen telescopically on the planet Jupiter.

Larger, better telescopes revealed them to be dynamic features in Jupiter’s dense atmosphere. The bands mark zones of

prevailing winds, somewhat analogous to Earth’s jet streams. The spots are cyclonic storms that rage along the turbulent

boundaries of the jet streams. The largest of these, dubbed the Great Red Spot (GRS), is a cold, high pressure area 2–3

times wider than planet Earth. Its winds travel at approximately 400 miles per hour—far surpassing the 155 miles per

hour wind speed of Earth’s own Category 5 hurricanes.

In the 1930s, astronomers documented the collapse of a white jet stream just south of the GRS that resulted in the creation

of three elongated features. During the next decade, astronomers watched these features morph into three distinct white

cyclonic storms. In 1998, these storms merged together to form one giant white storm. Its wind speeds now rival those of

the GRS and it has grown to nearly half its size. Then, abruptly in 2006—for reasons still not completely understood—that

storm turned red. Astronomers named it “Red Spot Jr,” or more formally, “Oval BA.”

In 2008, yet another red spot developed. Named “Baby Red Spot,” or “2008 Oval 2,” this new storm was just a fraction of

the size of the other two red spots. And unlike the others, its life span would be short—as it would be caught and absorbed

within months by the anticyclonic spin of the GRS.

All three red spots were imaged in detail using Hubble, by two teams of astronomers led by Imke de Pater of the University

of California, Berkeley and Amy Simon-Miller of NASA’s Goddard Space Flight Center. Hubble’s first image of 2008 Oval

2 was taken in May 2008. The spot was located just to the west of the GRS and was at the same basic latitude. Oval BA

was located between the two, although at a lower latitude.

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The close alignment among the red spots was short-lived. Hubble images taken one and two months after 2008 Oval 2’s

discovery revealed that the small spot had traversed from the west side of the GRS to the east side. The small spot’s ap-

pearance, however, was changed. The June and July images showed that 2008 Oval 2 was now trapped by the forces of

the GRS storm. As it slipped into the maelstrom of the GRS, 2008 Oval 2 was disintegrating and losing its color.

No one is certain what gives these storms their red color. One theory is that the storms are so powerful that they dredge

up gases or particulates from deep in Jupiter’s atmosphere to higher altitudes, where ultraviolet radiation disassociates the

elements within their molecules. Subsequent chemical reactions may lead to the red color. Astronomers speculate that the

color loss in 2008 Oval 2 was due to the loss of its upward cyclonic circulation once it was trapped and consumed by the

GRS.

This sequence of images shows the movement of the three red spots clustered together in Jupiter’s atmosphere. For the second time since turning red, Oval BA skirts past the Great Red Spot apparently unscathed. However, 2008 Oval 2 (identified by an arrow in the third panel) gets captured in the anticyclonic spin of the Great Red Spot.

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Multi-wavelength images showed that the clouds in 2008 Oval 2 did indeed rise high into Jupiter’s atmosphere before

merging into the GRS. The cloud levels were documented in visible-light images captured by Hubble and by near-infrared

data collected by the W.H. Keck Telescope in Hawaii. Astronomers determined that all three storms (the GRS, Oval BA, and

2008 Oval 2) appeared bright in near-infrared light, signaling that they were towering above the methane in Jupiter’s atmo-

sphere. Methane absorbs infrared light, so methane-rich planets like Jupiter appear dark in reflected sunlight.

As astronomers predicted, the GRS eventually consumed most of 2008 Oval 2, although some high clouds continued to

move eastward after the encounter. A steady energy source of small storms, such as that produced by 2008 Oval 2, may

be one reason why the huge GRS storm has sustained itself for so many years.

This false-color cylindrical map of Jupiter reveals the location of the newest red spot, 2008 Oval 2. Individual frames were obtained on May 9 and May 10, 2008 and mosaiced together to form this map with a resolution of a quarter degree in latitude and longitude. The red triangles at the top and bottom of the image are all areas of missing data.

System III West Longitude (degrees)

Plan

etog

raph

ic L

atitu

de (d

egre

es)

+30

–30

–60

+60

0

0306090120150180210240270300330360

GRS

BA

2008 Oval 2

Jupiter May 9–10, 2008 • Hubble Space Telescope WFPC2

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Further Reading

Aguirre, E.L., “Hubble Zooms in on Jupiter’s New Red Spot: The Great Red Spot’s Baby Brother Falls Under the Space Telescope’s Powerful Gaze,” Sky & Telescope, 112(2), 26–29, 2006.

Aguirre, E.L., “Jupiter’s Mini Red Spot Survives Encounter,” Sky & Telescope, 112(6), 86–87, 2006.

Barrado-Izagirre, N., et al., “Jupiter’s Polar Clouds and Waves from Cassini and HST Images: 1993–2006,” Icarus, 194(1), 173–185, 2008.

Cheng, A.F., et al., “Changing Characteristics of Jupiter’s Little Red Spot,” Astronomical Journal, 135(6), 2446–2452, 2008.

McAnally, J.W., Jupiter and How to Observe It, London: Springer-Verlag, 2008.

Simon-Miller, A.A., et al., “Jupiter’s White Oval Turns Red,” Icarus, 185(2), 558–562, 2006.

The mighty planet Jupiter is 11 times the diam-eter of Earth, but rotates in less than half the time. Changing features within its turbulent at-mosphere are noted and studied by amateur and professional astronomers alike.

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Amy Simon-Miller has observed Jupiter with the Hubble Space Telescope since 1993, including observa-

tions of the Great Red Spot in 2008. These data have been used to study the planet’s ever-changing

atmosphere in an effort to understand what powers the enigmatic storms and powerful winds. Born

and raised in Union, New Jersey, Dr. Simon-Miller earned a B.S. in space sciences from the Florida

Institute of Technology in 1993, and a Ph.D. in astronomy from New Mexico State University in 1998.

She is Chief of the Planetary Systems Laboratory at the NASA Goddard Space Flight Center, where

her focus is on understanding the atmospheres of Jupiter and Saturn and on designing future robotic

space missions.

Imke de Pater is a professor in the departments of Astronomy, and Earth and Planetary Science at the

University of California at Berkeley. Born in Hengelo, Netherlands, she received her Ph.D. cum laude

in 1980 from Leiden University. She started her career observing and modeling Jupiter’s synchrotron

radiation, followed by detailed investigations of the planet’s thermal radio emission. In 1994, she

led a worldwide campaign at radio wavelengths to observe the impact of comet D/Shoemaker-Levy

9 with Jupiter. She is currently exploiting adaptive optics techniques in the infrared range to obtain

high angular-resolution data of the volcanic activity on Io, the weather on Titan, planetary rings, and

Jupiter’s new red oval. She used the Hubble Space Telescope to study weather on Jupiter (in particular,

the red Oval BA), and to complement adaptive optics observations of planetary rings with visible

wavelength data. She teamed up with Jack Lissauer to write a book called Planetary Sciences, which is

the graduate-level textbook in this field. (Photo credit: S. Anderson, Keck Observatory)

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