pio11_v_bw_o_n (AC74-9213.1-B, AC74-9213)
“This view, looking northward toward the equator, is the closest picture of Jupiter’s Great Red Spot taken by Pioneer 11. (Distance is 545,000 km or 338,000 mi).
More details of the Great Red Spot (which is large enough to swallow three Earths) and its surrounding region are visible here than have ever been seen before. The picture was taken in red and blue light and color.
Details of the flow, already known to exist, of the white cloud streams north of the Spot [flow] from right to left in the picture, and flow from left to right in the strip of clouds south of the Spot is clearly visible. The triangular regions on either side of the Spot appear to be areas where these two streams converge to flow side-by-side in opposite directions.
Details visible within the Spot (especially in the blue light picture) seem to show counterclockwise spiral there. Theory suggests that the Spot rotates counterclockwise due to the flow in the opposite directions of cloud streams north and south of it.
There also appears to be a narrow jet stream of brown material flowing southwestward above and to the left of the Spot. Strung out along the boundary between the white South Tropical zone, containing the Spot, and the brown belt north of it, is a series of small, white cloud puffs. (Puffs are only relatively small, typically about the size of Ohio). The puffs may be an example of flow instability between the zone and belt, where cloud currents are fastest relative to the planet.
The white oval below the right end of the Great Red Spot is one of three white ovals which are usually 120° apart around Jupiter, and have been known for 30 years. The oval’s position relative to the Red Spot changes with time due to a different rate of flow of the cloud current which contains it. New details of the white oval in this picture, such as the circular “eye” in its center, strongly suggest rotational motion.
Between the Red Spot and the white oval is a stream of brownish cloud material. Turbulance extending out to the right of the Spot seems to show (especially in the red light view) a large wake created by this atmosphere stream. This cloud stream appears to be one of the first examples seen of transfer of mass between the belts and zones, something predicted by theories on Jovian meteorology.
Pioneer 11, which took the picture, flew past Jupiter last December. The Pioneer Project is managed by NASA’s Ames Research Center, Mountain View, Ca. The spacecraft were built by TRW Systems.
Scientists believe that understanding of Jupiter’s Meteorology, and of other planets, will be of major importance in the understanding of weather on Earth.”
Also, the image (in color) and associated caption, on page 20:
“One of the best Pioneer images of Jupiter was obtained at a range of 545000 kilometers by Pioneer 11. Structure withing the Great Red Spot and the surrounding belts and zones can be seen. There was less turbulent cloud activity around the Spot at the times of the Pioneer flybys then was seen five years later by the Voyager cameras.”
At:
ntrs.nasa.gov/citations/19820018276
Finally:
From “NASA SP-446/PIONEER: FIRST TO JUPITER, SATURN, AND BEYOND”, pages 169 & 170 where the orthographic(?) projection of the image is shown as; (a) color composite, (b) blue channel image, and (c) red channel image, with the following accompanying text:
“For planetary astronomers, this image of the Great Red Spot of Jupiter was one of Pioneer 11’s most exciting results. From Pioneer 10, the highest-resolution image of the spot had been degraded by radiation problems, but Pioneer 11 obtained this unique image (Figure 9-11a). The area covered by the image on the planet is shown in the line drawing insert (d) on this page.
The image, obtained 545,000 km (339,000 miles) above the cloud tops, contains more than 4,000 individual pixels (see chapter 7) of measurable data in the red area of the spot a wealth of detailed markings since each pixel represents an area of approximately 237 km (147 miles) square. Scientists will be able to compare this image with those obtained by other spacecraft in later years to ascertain how the structure of the Spot changes with time.
Planetary scientists have derived new interpretations of the Great Red Spot from this image. Despite the relatively high resolution obtained, there is much less fine structure visible in the spot than in comparable areas at other latitudes (e.g., in Figure 9-12 and 914). The Great Red Spot appears to lie in the most quiescent zone of Jupiter, which may contribute to its stability.
The blue image has little internal detail (Figure 9-11b), the main feature being the dark border on the periphery of the spot. A break appears in the border in the northeast portion of the spot, where some of the red material appears to intermix with the South Tropical Zone.
The red image reveals much internal detail (Figure 9-11c), perhaps the most significant being two circular outlines that cross over near the center of the spot. This same feature also appeared in the Pioneer 10 images. This image does not show clear evidence of motions within the spot. The image does not show direct evidence of flow lines from any single region inside the spot, which could he interpreted as a source or a sink of red material.”
From/at:
atmos.nmsu.edu/data_and_services/atmospheres_data/SATURN/...
pio11_v_bw_o_n (AC74-9213.1-B, AC74-9213)
“This view, looking northward toward the equator, is the closest picture of Jupiter’s Great Red Spot taken by Pioneer 11. (Distance is 545,000 km or 338,000 mi).
More details of the Great Red Spot (which is large enough to swallow three Earths) and its surrounding region are visible here than have ever been seen before. The picture was taken in red and blue light and color.
Details of the flow, already known to exist, of the white cloud streams north of the Spot [flow] from right to left in the picture, and flow from left to right in the strip of clouds south of the Spot is clearly visible. The triangular regions on either side of the Spot appear to be areas where these two streams converge to flow side-by-side in opposite directions.
Details visible within the Spot (especially in the blue light picture) seem to show counterclockwise spiral there. Theory suggests that the Spot rotates counterclockwise due to the flow in the opposite directions of cloud streams north and south of it.
There also appears to be a narrow jet stream of brown material flowing southwestward above and to the left of the Spot. Strung out along the boundary between the white South Tropical zone, containing the Spot, and the brown belt north of it, is a series of small, white cloud puffs. (Puffs are only relatively small, typically about the size of Ohio). The puffs may be an example of flow instability between the zone and belt, where cloud currents are fastest relative to the planet.
The white oval below the right end of the Great Red Spot is one of three white ovals which are usually 120° apart around Jupiter, and have been known for 30 years. The oval’s position relative to the Red Spot changes with time due to a different rate of flow of the cloud current which contains it. New details of the white oval in this picture, such as the circular “eye” in its center, strongly suggest rotational motion.
Between the Red Spot and the white oval is a stream of brownish cloud material. Turbulance extending out to the right of the Spot seems to show (especially in the red light view) a large wake created by this atmosphere stream. This cloud stream appears to be one of the first examples seen of transfer of mass between the belts and zones, something predicted by theories on Jovian meteorology.
Pioneer 11, which took the picture, flew past Jupiter last December. The Pioneer Project is managed by NASA’s Ames Research Center, Mountain View, Ca. The spacecraft were built by TRW Systems.
Scientists believe that understanding of Jupiter’s Meteorology, and of other planets, will be of major importance in the understanding of weather on Earth.”
Also, the image (in color) and associated caption, on page 20:
“One of the best Pioneer images of Jupiter was obtained at a range of 545000 kilometers by Pioneer 11. Structure withing the Great Red Spot and the surrounding belts and zones can be seen. There was less turbulent cloud activity around the Spot at the times of the Pioneer flybys then was seen five years later by the Voyager cameras.”
At:
ntrs.nasa.gov/citations/19820018276
Finally:
From “NASA SP-446/PIONEER: FIRST TO JUPITER, SATURN, AND BEYOND”, pages 169 & 170 where the orthographic(?) projection of the image is shown as; (a) color composite, (b) blue channel image, and (c) red channel image, with the following accompanying text:
“For planetary astronomers, this image of the Great Red Spot of Jupiter was one of Pioneer 11’s most exciting results. From Pioneer 10, the highest-resolution image of the spot had been degraded by radiation problems, but Pioneer 11 obtained this unique image (Figure 9-11a). The area covered by the image on the planet is shown in the line drawing insert (d) on this page.
The image, obtained 545,000 km (339,000 miles) above the cloud tops, contains more than 4,000 individual pixels (see chapter 7) of measurable data in the red area of the spot a wealth of detailed markings since each pixel represents an area of approximately 237 km (147 miles) square. Scientists will be able to compare this image with those obtained by other spacecraft in later years to ascertain how the structure of the Spot changes with time.
Planetary scientists have derived new interpretations of the Great Red Spot from this image. Despite the relatively high resolution obtained, there is much less fine structure visible in the spot than in comparable areas at other latitudes (e.g., in Figure 9-12 and 914). The Great Red Spot appears to lie in the most quiescent zone of Jupiter, which may contribute to its stability.
The blue image has little internal detail (Figure 9-11b), the main feature being the dark border on the periphery of the spot. A break appears in the border in the northeast portion of the spot, where some of the red material appears to intermix with the South Tropical Zone.
The red image reveals much internal detail (Figure 9-11c), perhaps the most significant being two circular outlines that cross over near the center of the spot. This same feature also appeared in the Pioneer 10 images. This image does not show clear evidence of motions within the spot. The image does not show direct evidence of flow lines from any single region inside the spot, which could he interpreted as a source or a sink of red material.”
From/at:
atmos.nmsu.edu/data_and_services/atmospheres_data/SATURN/...