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PIA00221: Venus - Lower-level Clouds As Seen By NIMS

These images are two versions of a near-infrared map of lower-level clouds on the night side of Venus, obtained by the Near Infrared Mapping Spectrometer aboard the Galileo spacecraft as it approached the planet February 10, 1990. Taken from an altitude of about 60,000 miles above the planet, at an infrared wavelength of 2.3 microns (about three times the longest wavelength visible to the human eye) the map shows the turbulent, cloudy middle atmosphere some 30-33 miles above the surface, 6-10 miles below the visible cloudtops. The image to the left shows the radiant heat from the lower atmosphere (about 400 degrees Fahrenheit) shining through the sulfuric acid clouds, which appear as much as 10 times darker than the bright gaps between clouds. This cloud layer is at about -30 degrees Fahrenheit, at a pressure about 1/2 Earth's atmospheric pressure. About 2/3 of the dark hemisphere is visible, centered on longitude 350 West, with bright slivers of daylit high clouds visible at top and bottom left. The right image, a modified negative, represents what scientists believe would be the visual appearance of this mid-level cloud deck in daylight, with the clouds reflecting sunlight instead of blocking out infrared from the hot planet and lower atmosphere. Near the equator, the clouds appear fluffy and blocky; farther north, they are stretched out into East-West filaments by winds estimated at more than 150 mph, while the poles are capped by thick clouds at this altitude. The Near Infrared Mapping Spectrometer (NIMS) on the Galileo spacecraft is a combined mapping (imaging) and spectral instrument. It can sense 408 contiguous wavelengths from 0.7 microns (deep red) to 5.2 microns, and can construct a map or image by mechanical scanning. It can spectroscopically analyze atmospheres and surfaces and construct thermal and chemical maps. Designed and operated by scientists and engineers at the Jet Propulsion Laboratory, NIMS involves 15 scientists in the U.S., England, and France. The Galileo Project is managed for NASA's Office of Space Science and Applications by JPL; its mission is to study the planet Jupiter and its satellites and magnetosphere after multiple gravity-assist flybys at Venus and the Earth.

Voir l'image PIA00221: Venus - Lower-level Clouds As Seen By NIMS sur le site de la NASA.
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PIA00104: Venus - Computer Simulated Global View Centered at 180 Degrees East Longitude

This global view of the surface of Venus is centered at 180 degrees east longitude. Magellan synthetic aperture radar mosaics from the first cycle of Magellan mapping are mapped onto a computer-simulated globe to create this image. Data gaps are filled with Pioneer Venus Orbiter data, or a constant mid-range value. Simulated color is used to enhance small-scale structure. The simulated hues are based on color images recorded by the Soviet Venera 13 and 14 spacecraft. The image was produced by the Solar System Visualization project and the Magellan science team at the JPL Multimission Image Processing Laboratory and is a single frame from a video released at the October 29, 1991, JPL news conference.

Voir l'image PIA00104: Venus - Computer Simulated Global View Centered at 180 Degrees East Longitude sur le site de la NASA.
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PIA00270: Venus - Computer Simulated Global View Centered at 90 Degrees East Longitude

This global view of the surface of Venus is centered at 90 degrees east longitude. Magellan synthetic aperture radar mosaics from the three eight-month cycles of Magellan radar mapping are mapped onto a computer-simulated globe to create this image. Magellan obtained coverage of 98 percent of the surface of Venus. Remaining gaps are filled with data from previous Venus missions -- the Venera 15 and 16 radar and Pioneer-Venus Orbiter altimetry -- and data from Earth-based radar observations from the Arecibo radio telescope. Simulated color is used to enhance small-scale structures. The simulated hues are based on color images obtained by the Venera 13 and 14 landing craft. The bright feature near the center of the image is Ovda Regio, a mountainous region in the western portion of the great Aphrodite equatorial highland. The dark areas scattered across the Venusian plains consist of extremely smooth deposits associated with large meteorite impacts. The image was produced by the Solar System Visualization Project and the Magellan Science team at the Jet Propulsion Laboratory Multimission Image Processing Laboratory. The Magellan mission is managed by JPL for NASA's Office of Space Science.

Voir l'image PIA00270: Venus - Computer Simulated Global View Centered at 90 Degrees East Longitude sur le site de la NASA.
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PIA00160: Hemispheric View of Venus Centered at 270° East Longitude

The hemispheric view of Venus, as revealed by more than a decade of radar investigations culminating in the 1990-1994 Magellan mission, is centered at 270 degrees east longitude. The Magellan spacecraft imaged more than 98% of Venus at a resolution of about 100 meters; the effective resolution of this image is about 3 km. A mosaic of the Magellan images (most with illumination from the west) forms the image base. Gaps in the Magellan coverage were filled with images from the Earth-based Arecibo radar in a region centered roughly on 0 degree latitude and longitude, and with a neutral tone elsewhere (primarily near the south pole). The composite image was processed to improve contrast and to emphasize small features, and was color-coded to represent elevation. Gaps in the elevation data from the Magellan radar altimeter were filled with altimetry from the Venera spacecraft and the U.S. Pioneer Venus missions. An orthographic projection was used, simulating a distant view of one hemisphere of the planet. The Magellan mission was managed for NASA by Jet Propulsion Laboratory (JPL), Pasadena, CA. Data processed by JPL, the Massachusetts Institute of Technology, Cambridge, MA, and the U.S. Geological Survey, Flagstaff, AZ.

Voir l'image PIA00160: Hemispheric View of Venus Centered at 270° East Longitude sur le site de la NASA.

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PIA00071: Venus in Violet and Near Infrared Light

These images of the Venus clouds were taken by Galileo's Solid State Imaging System February 13,1990, at a range of about 1 million miles. The smallest detail visible is about 20 miles. The two right images show Venus in violet light, the top one at a time six hours later than the bottom one. They show the state of the clouds near the top of Venus's cloud deck. A right to left motion of the cloud features is evident and is consistent with westward winds of about 230 mph. The two left images show Venus in near infrared light, at the same times as the two right images. Sunlight penetrates through the clouds more deeply at the near infrared wavelengths, allowing a view near the bottom of the cloud deck. The westward motion of the clouds is slower (about 150 mph) at the lower altitude. The clouds are composed of sulfuric acid droplets and occupy a range of altitudes from 30 to 45 miles. The images have been spatially filtered to bring out small scale details and de-emphasize global shading. The filtering has introduced artifacts (wiggly lines running north/south) that are faintly visible in the infrared image. The Galileo Project is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory; its mission is to study Jupiter and its satellites and magnetosphere after multiple gravity assist flybys at Venus and Earth.

Voir l'image PIA00071: Venus in Violet and Near Infrared Light sur le site de la NASA.

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PIA00252: Venus - Computer Simulated Global View of Northern Hemisphere

The northern hemisphere is displayed in this global view of the surface of Venus. The north pole is at the center of the image, with 0 degrees, 90 degrees, 180 degrees, 270 degrees east longitudes at the 6, 3, 12, 9 o'clock positions, respectively, of an imaginary clock face. Magellan synthetic aperture radar mosaics from the first cycle of Magellan mapping are mapped onto a computer-simulated globe to create this image. Data gaps are filled with Pioneer Venus Orbiter data, or a constant mid-range value. Simulated color is used to enhance small-scale structure. The simulated hues are based on color images recorded by the Soviet Venera 13 and 14 spacecraft. The image was produced at the JPL Multimission Image Processing Laboratory and is a single frame from a video released at the October 29, 1991, JPL news conference.

Voir l'image PIA00252: Venus - Computer Simulated Global View of Northern Hemisphere sur le site de la NASA.
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PIA01544: Venus Cloud Tops Viewed by Hubble

Venus Cloud Tops Viewed by Hubble. This is a NASA Hubble Space Telescope ultraviolet-light image of the planet Venus, taken on January 24 1995, when Venus was at a distance of 70.6 million miles (113.6 million kilometers) from Earth. Venus is covered with clouds made of sulfuric acid, rather than the water-vapor clouds found on Earth. These clouds permanently shroud Venus' volcanic surface, which has been radar mapped by spacecraft and from Earth-based telescope. At ultraviolet wavelengths cloud patterns become distinctive. In particular, a horizontal "Y"-shaped cloud feature is visible near the equator. Similar features were seen from Mariner 10, Pioneer Venus, and Galileo spacecrafts. This global feature might indicate atmospheric waves, analogous to high and low pressure cells on Earth. Bright clouds toward Venus' poles appear to follow latitude lines. The polar regions are bright, possibly showing a haze of small particles overlying the main clouds. The dark regions show the location of enhanced sulfur dioxide near the cloud tops. From previous missions, astronomers know that such features travel east to west along with the Venus' prevailing winds, to make a complete circuit around the planet in four days. Because Venus is closer to the Sun than Earth, the planet appears to go through phases, like the Moon. When Venus swings close to Earth the planet's disk appears to grow in size, but changes from a full disk to a crescent. The image was taken with the Wide Field Planetary Camera-2, in PC mode. False color has been used enhance cloud features.

Voir l'image PIA01544: Venus Cloud Tops Viewed by Hubble sur le site de la NASA.

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PIA00271: Venus - Computer Simulated Global View of the Northern Hemisphere

The northern hemisphere is displayed in this global view of the surface of Venus. The north pole is at the center of the image, with 0 degrees, 90 degrees, 180 degrees, 270 degrees east longitudes at the 6, 3, 12, and 9 o'clock positions, respectively, of an imaginary clock face. Magellan synthetic aperture radar mosaics from the three eight-month cycles of Magellan radar mapping are mapped onto a computer-simulated globe to create this image. Magellan obtained coverage of 98 percent of the surface of Venus. Remaining gaps are filled with data from previous missions, (the Soviet Venera 15 and 16 radar and Pioneer Venus Orbiter altimetry) and data from Earth-based radar observations from the Arecibo radio telescope. Simulated color is used to enhance small-scale structures. The simulated hues are based on color images recorded by the Venera 13 and 14 landing craft. Maxwell Montes, the planet's highest mountain at 11 kilometers (6.6 miles) above the average elevation, is the bright feature in the lower center of the image. Other terrain types visible in this image include tessera, ridge belts, lava flows, impact craters and coronae. The image was produced by the Solar System Visualization Project and the Magellan Science team at the Jet Propulsion Laboratory Multimission Image Processing Laboratory. The Magellan mission is managed by JPL for NASA's Office of Space Science.

Voir l'image PIA00271: Venus - Computer Simulated Global View of the Northern Hemisphere sur le site de la NASA.
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PIA00159: Hemispheric View of Venus Centered at 180° East Longitude

The hemispheric view of Venus, as revealed by more than a decade of radar investigations culminating in the 1990-1994 Magellan mission, is centered at 180 degrees east longitude. The Magellan spacecraft imaged more than 98% of Venus at a resolution of about 100 meters; the effective resolution of this image is about 3 km. A mosaic of the Magellan images (most with illumination from the west) forms the image base. Gaps in the Magellan coverage were filled with images from the Earth-based Arecibo radar in a region centered roughly on 0 degree latitude and longitude, and with a neutral tone elsewhere (primarily near the south pole). The composite image was processed to improve contrast and to emphasize small features, and was color-coded to represent elevation. Gaps in the elevation data from the Magellan radar altimeter were filled with altimetry from the Venera spacecraft and the U.S. Pioneer Venus missions. An orthographic projection was used, simulating a distant view of one hemisphere of the planet. The Magellan mission was managed for NASA by Jet Propulsion Laboratory (JPL), Pasadena, CA. Data processed by JPL, the Massachusetts Institute of Technology, Cambridge, MA, and the U.S. Geological Survey, Flagstaff, AZ.

Voir l'image PIA00159: Hemispheric View of Venus Centered at 180° East Longitude sur le site de la NASA.

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PIA00073: Venus as Viewed Through Violet and Near Infrared Filters

These two Galileo images of Venus show the global structure of cloud patterns at two different depths in the upper cloud layers. The large bluish image, taken through the violet filter, shows patterns at the very top of Venus' main sulfuric acid haze layer. The subsolar point is to the right, not far from the limb; the atmospheric flow runs to the left from there. The small red image, taken through a near infrared filter, shows the cloud patterns several miles below the visible cloud tops. The colors shown are artificial; the images were enhanced at the National Optical Astronomy Observatories, Tucson, Arizona. The Galileo Project is managed for NASA by the Jet Propulsion Laboratory.

Voir l'image PIA00073: Venus as Viewed Through Violet and Near Infrared Filters sur le site de la NASA.

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PIA00157: Hemispheric View of Venus Centered at 0 Degrees East Longitude

The hemispheric view of Venus, as revealed by more than a decade of radar investigations culminating in the 1990-1994 Magellan mission, is centered at 0 degrees east longitude. The Magellan spacecraft imaged more than 98% of Venus at a resolution of about 100 meters; the effective resolution of this image is about 3 km. A mosaic of the Magellan images (most with illumination from the west) forms the image base. Gaps in the Magellan coverage were filled with images from the Earth-based Arecibo radar in a region centered roughly on 0 degree latitude and longitude, and with a neutral tone elsewhere (primarily near the south pole). The composite image was processed to improve contrast and to emphasize small features, and was color-coded to represent elevation. Gaps in the elevation data from the Magellan radar altimeter were filled with altimetry from the Venera spacecraft and the U.S. Pioneer Venus missions. An orthographic projection was used, simulating a distant view of one hemisphere of the planet. The Magellan mission was managed for NASA by Jet Propulsion Laboratory (JPL), Pasadena, CA. Data processed by JPL, the Massachusetts Institute of Technology, Cambridge, MA, and the U.S. Geological Survey, Flagstaff, AZ.

Voir l'image PIA00157: Hemispheric View of Venus Centered at 0 Degrees East Longitude sur le site de la NASA.
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PIA00008: Hemispheric View of Venus Centered at the South Pole

The hemispheric view of Venus, as revealed by more than a decade of radar investigations culminating in the 1990-1994 Magellan mission, is centered on the South Pole. The Magellan spacecraft imaged more than 98% of Venus at a resolution of about 100 meters; the effective resolution of this image is about 3 km. A mosaic of the Magellan images (most with illumination from the west) forms the image base. Gaps in the Magellan coverage were filled with images from the Earth-based Arecibo radar in a region centered roughly on 0 degree latitude and longitude, and with a neutral tone elsewhere (primarily near the south pole). The composite image was processed to improve contrast and to emphasize small features, and was color-coded to represent elevation. Gaps in the elevation data from the Magellan radar altimeter were filled with altimetry from the Venera spacecraft and the U.S. Pioneer Venus missions. An orthographic projection was used, simulating a distant view of one hemisphere of the planet. The Magellan mission was managed for NASA by the Jet Propulsion Laboratory (JPL), Pasadena, CA. Data processed by JPL, the Massachusetts Institute of Technology, Cambridge, MA, and the U.S. Geological Survey, Flagstaff, AZ.

Voir l'image PIA00008: Hemispheric View of Venus Centered at the South Pole sur le site de la NASA.

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PIA00110: Four Views of Venus (High Pass Filter)

These are enhanced versions of four views of the planet Venus taken by the Galileo's Solid State Imaging System at distances ranging from 1.4 to 2 million miles as the spacecraft receded from Venus. The pictures in the top row were taken about 4 and 5 days after closest approach, and those in the bottom row six days after closest approach, 2 hours apart. These show the faint Venusian cloud features especially clearly. A high-pass filter was applied to bring out broader global variations in tone. The bright polar hoods are a well-known feature of Venus. Of particular interest to planetary atmospheric scientists are the complex cloud patterns near the equator, in the vicinity of the bright subsolar point, where convection is most prevalent. The Galileo Project is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory; its mission is to study Jupiter and its satellites and magnetosphere after multiple gravity-assist flybys at Venus and Earth.

Voir l'image PIA00110: Four Views of Venus (High Pass Filter) sur le site de la NASA.
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PIA00478: Venus - Global View Centered at 180 degrees

This global view of the surface of Venus is centered at 180 degrees east longitude. Magellan synthetic aperture radar mosaics from the first cycle of Magellan mapping, and a 5 degree latitude-longitude grid, are mapped onto a computer-simulated globe to create this image. Data gaps are filled with Pioneer-Venus Orbiter data, or a constant mid-range value. The image was produced by the Solar System Visualization project and the Magellan Science team at the JPL Multimission Image Processing Laboratory.

Voir l'image PIA00478: Venus - Global View Centered at 180 degrees sur le site de la NASA.
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PIA00223: Venus - Multiple Views of High-level Clouds

This series of pictures shows four views of the planet Venus obtained by Galileo's Solid State Imaging System at ranges of 1.4 to 2 million miles as the spacecraft receded from Venus. The pictures in the top row were taken about 4 and 5 days after closest approach; those in the bottom row were taken about 6 days out, 2 hours apart. In these violet-light images, north is at the top and the evening terminator to the left. The cloud features high in the planet's atmosphere rotate from right to left, from the limb through the noon meridian toward the terminator, traveling all the way around the planet once every four days. The motion can be seen by comparing the last two pictures, taken two hours apart. The other views show entirely different faces of Venus. These photographs are part of the 'Venus global circulation' sequence planned by the imaging team. The Galileo Project is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory; its mission is to study Jupiter and its satellites and magnetosphere after multiple gravity-assist flybys at Venus and Earth.

Voir l'image PIA00223: Venus - Multiple Views of High-level Clouds sur le site de la NASA.
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PIA10123: Approaching Venus

On Oct. 24, 2006, the MESSENGER spacecraft came within 2,990 kilometers (1,860 miles) of Venus during its second planetary encounter. Twenty days before closest approach to Venus the MESSENGER Dual Imaging System snapped pictures of the planet from a distance of about 16.5 million kilometers (10.3 million miles). Despite the low resolution of the image on the left, one can see that Venus is shrouded in a thick blanket of clouds that hides its surface. The picture on the right is the same image expanded four times, clearly showing the dense Venusian cloud cover.

These images are from MESSENGER, a NASA Discovery mission to conduct the first orbital study of the innermost planet, Mercury. For information regarding the use of images, see the MESSENGER image use policy.

Voir l'image PIA10123: Approaching Venus sur le site de la NASA.

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PIA10124: Approaching Venus Image #2

The MESSENGER spacecraft snapped a series of images as it approached Venus on June 5. The planet is enshrouded by a global layer of clouds that obscures its surface to the MESSENGER Dual Imaging System (MDIS) cameras.

This single frame is part of a color sequence taken to help the MESSENGER team calibrate the camera in preparation for the spacecraft's first flyby of Mercury on January 14, 2008. Over the next several months the camera team will pore over the 614 images taken during this Venus encounter to ascertain color sensitivity and other optical properties of the instrument. These tasks address two key goals for the camera at Mercury: understanding surface color variations and their relation to compositional variations in the crust, and ensuring accurate cartographic placement of features on Mercury's surface.

Preliminary analysis of the Venus flyby images indicates that the cameras are healthy and will be ready for next January's close encounter with Mercury.

These images are from MESSENGER, a NASA Discovery mission to conduct the first orbital study of the innermost planet, Mercury. For information regarding the use of images, see the MESSENGER image use policy.

Voir l'image PIA10124: Approaching Venus Image #2 sur le site de la NASA.

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PIA00111: Venus Colorized Clouds

This colorized picture of Venus was taken February 14, 1990, from a distance of almost 1.7 million miles, about 6 days after Galileo's closest approach to the planet. It has been colorized to a bluish hue to emphasize subtle contrasts in the cloud markings and to indicate that it was taken through a violet filter. Features in the sulfuric acid clouds near the top of the planet's atmosphere are most prominent in violet and ultraviolet light. This image shows the east-to-west-trending cloud banding and the brighter polar hoods familiar from past studies of Venus. The features are embedded in winds that flow from east to west at about 230 mph. The smallest features visible are about 45 miles across. An intriguing filamentary dark pattern is seen immediately left of the bright region at the subsolar point (equatorial 'noon'). North is at the top and the evening terminator is to the left. The Galileo Project is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory; its mission is to study Jupiter and its satellites and magnetosphere after multiple gravity-assist flybys at Venus and Earth.

Voir l'image PIA00111: Venus Colorized Clouds sur le site de la NASA.
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PIA00072: Venus Cloud Patterns (colorized and filtered)

This picture of Venus was taken by the Galileo spacecrafts Solid State Imaging System on February 14, 1990, at a range of almost 1.7 million miles from the planet. A highpass spatial filter has been applied in order to emphasize the smaller scale cloud features, and the rendition has been colorized to a bluish hue in order to emphasize the subtle contrasts in the cloud markings and to indicate that it was taken through a violet filter. The sulfuric acid clouds indicate considerable convective activity, in the equatorial regions of the planet to the left and downwind of the subsolar point (afternoon on Venus). They are analogous to "fair weather clouds" on Earth. The filamentary dark features visible in the colorized image are here revealed to be composed of several dark nodules, like beads on a string, each about 60 miles across. The Galileo Project is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory; its mission is to study Jupiter and its satellites and magnetosphere after multiple gravity assist flybys at Venus and Earth. These images of the Venus clouds were taken by Galileo's Solid State Imaging System February 13, 1990, at a range of about 1 million miles. The smallest detail visible is about 20 miles. The two right images show Venus in violet light, the top one at a time six hours later than the bottom one. They show the state of the clouds near the top of Venus's cloud deck. A right to left motion of the cloud features is evident and is consistent with westward winds of about 230 mph. The two left images show Venus in near infrared light, at the same times as the two right images. Sunlight penetrates through the clouds more deeply at the near infrared wavelengths, allowing a view near the bottom of the cloud deck. The westward motion of the clouds is slower (about 150 mph) at the lower altitude. The clouds are composed of sulfuric acid droplets and occupy a range of altitudes from 30 to 45 miles. The images have been spatially filtered to bring out small scale details and de-emphasize global shading. The filtering has introduced artifacts (wiggly lines running north/south) that are faintly visible in the infrared image. The Galileo Project is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory; its mission is to study Jupiter and its satellites and magnetosphere after multiple gravity assist flybys at Venus and Earth.

Voir l'image PIA00072: Venus Cloud Patterns (colorized and filtered) sur le site de la NASA.

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PIA00124: Infrared Image of Low Clouds on Venus

This false-color image is a near-infrared map of lower-level clouds on the night side of Venus, obtained by the Near Infrared Mapping Spectrometer aboard the Galileo spacecraft as it approached the planet's night side on February 10, 1990. Bright slivers of sunlit high clouds are visible above and below the dark, glowing hemisphere. The spacecraft is about 100,000 kilometers (60,000 miles) above the planet. An infrared wavelength of 2.3 microns (about three times the longest wavelength visible to the human eye) was used. The map shows the turbulent, cloudy middle atmosphere some 50-55 kilometers (30- 33 miles) above the surface, 10-16 kilometers or 6-10 miles below the visible cloudtops. The red color represents the radiant heat from the lower atmosphere (about 400 degrees Fahrenheit) shining through the sulfuric acid clouds, which appear as much as 10 times darker than the bright gaps between clouds. This cloud layer is at about -30 degrees Fahrenheit, at a pressure about 1/2 Earth's surface atmospheric pressure. Near the equator, the clouds appear fluffy and blocky; farther north, they are stretched out into East-West filaments by winds estimated at more than 150 mph, while the poles are capped by thick clouds at this altitude.

Voir l'image PIA00124: Infrared Image of Low Clouds on Venus sur le site de la NASA.
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PIA00158: Hemispheric View of Venus Centered at 90 Degrees East Longitude

The hemispheric view of Venus, as revealed by more than a decade of radar investigations culminating in the 1990-1994 Magellan mission, is centered at 90 degrees east longitude. The Magellan spacecraft imaged more than 98% of Venus at a resolution of about 100 meters; the effective resolution of this image is about 3 km. A mosaic of the Magellan images (most with illumination from the west) forms the image base. Gaps in the Magellan coverage were filled with images from the Earth-based Arecibo radar in a region centered roughly on 0 degree latitude and longitude, and with a neutral tone elsewhere (primarily near the south pole). The composite image was processed to improve contrast and to emphasize small features, and was color-coded to represent elevation. Gaps in the elevation data from the Magellan radar altimeter were filled with altimetry from the Venera spacecraft and the U.S. Pioneer Venus missions. An orthographic projection was used, simulating a distant view of one hemisphere of the planet. The Magellan mission was managed for NASA by Jet Propulsion Laboratory (JPL), Pasadena, CA. Data processed by JPL, the Massachusetts Institute of Technology, Cambridge, MA, and the U.S. Geological Survey, Flagstaff, AZ.

Voir l'image PIA00158: Hemispheric View of Venus Centered at 90 Degrees East Longitude sur le site de la NASA.
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PIA00007: Hemispheric View of Venus Centered at the North Pole

The hemispheric view of Venus, as revealed by more than a decade of radar investigations culminating in the 1990-1994 Magellan mission, is centered on the North Pole. The Magellan spacecraft imaged more than 98% of Venus at a resolution of about 100 meters; the effective resolution of this image is about 3 km. A mosaic of the Magellan images (most with illumination from the west) forms the image base. Gaps in the Magellan coverage were filled with images from the Earth-based Arecibo radar in a region centered roughly on 0 degree latitude and longitude, and with a neutral tone elsewhere (primarily near the south pole). The composite image was processed to improve contrast and to emphasize small features, and was color-coded to represent elevation. Gaps in the elevation data from the Magellan radar altimeter were filled with altimetry from the Venera spacecraft and the U.S. Pioneer Venus missions. An orthographic projection was used, simulating a distant view of one hemisphere of the planet. The Magellan mission was managed for NASA by Jet Propulsion Laboratory (JPL), Pasadena, CA. Data processed by JPL, the Massachusetts Institute of Technology, Cambridge, MA, and the U.S. Geological Survey, Flagstaff, AZ.

Voir l'image PIA00007: Hemispheric View of Venus Centered at the North Pole sur le site de la NASA.

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PIA10125: MESSENGER Bids Farewell to Venus


Click on image for
Venus Departure Sequence

After acquiring hundreds of high-resolution images during close approach to Venus, MESSENGER turned its wide-angle camera back to the planet and acquired a departure sequence. These images provide a spectacular good-bye to the cloud-shrouded planet while also providing valuable data to the camera calibration team. MESSENGER was 60,688 kilometers (37,710 miles) from the planet at the start of the sequence and 89,310 kilometers (55,495 miles) at the end. Initially, images were acquired at a rate of one of every 20 minutes, and then as Venus shrank the timing interval was increased to 60 minutes.

The first image was taken June 6 at 12:58 UTC (8:58 p.m. EDT on June 5), and the final image on June 7 at 02:18 UTC (10:18 p.m. EDT on June 6). During this 25 hour, 20 minute period the spacecraft traveled 833,234 kilometers (517,748 miles-more than twice the distance from the Earth to the Moon) with respect to Venus at an average speed of 9.13 kilometers per second (5.67 miles per second).

These images represent the last view of Venus by MESSENGER, but they also point toward the spacecraft's first encounter with Mercury in January 2008.

Departure sequence consists of MDIS frames EW0089578826F through EW0089670026F (430-nm wavelength filter).

These images are from MESSENGER, a NASA Discovery mission to conduct the first orbital study of the innermost planet, Mercury. For information regarding the use of images, see the MESSENGER image use policy.

Voir l'image PIA10125: MESSENGER Bids Farewell to Venus sur le site de la NASA.

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PIA00257: Venus - Computer Simulated Global View Centered at 0 Degrees East Longitude

This global view of the surface of Venus is centered at 0 degrees east longitude. Magellan synthetic aperture radar mosaics from the first cycle of Magellan mapping are mapped onto a computer-simulated globe to create this image. Data gaps are filled with Pioneer Venus Orbiter data, or a constant mid-range value. Simulated color is used to enhance small-scale structure. The simulated hues are based on color images recorded by the Soviet Venera 13 and 14 spacecraft. The image was produced by the Solar System Visualization project and the Magellan Science team at the JPL Multimission Image Processing Laboratory, and is a single frame from a video released at the October 29, 1991, JPL news conference.

Voir l'image PIA00257: Venus - Computer Simulated Global View Centered at 0 Degrees East Longitude sur le site de la NASA.
| | PIA00257: Venus - Computer Simulated Global View Centered at 0 Degrees East Longitude