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Collection:
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NASA Planetary Photo Journal Collection
Collection
NASA Planetary Photo Journal Collection
Collection
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Title:
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Mangala Fossa
Title
Mangala Fossa
Title
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Original Caption Released with Image:
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(Released 29 May 2002)
The Science
Today's THEMIS release captures Mangala Fossa. Mangala Fossa is a graben, which in geologic terminology translates into a long parallel to semi-parallel fracture or trough. Grabens are dropped or downthrown areas relative to the rocks on either side and these features are generally longer than they are wider. There are numerous dust devil trails seen in this image. In the lower portion of this image several dust devil tracks can be seen cutting across the upper surface then down the short stubby channel and finally back up and over to the adjacent upper surface. Some dust avalanche streaks on slopes are also visible. The rough material in the upper third of the image contains a portion of the rim of a 90 km diameter crater located in Daedalia Planum. The smooth crater floor has a graben (up to 7 km wide) and channel (2 km wide) incised into its surface. In the middle third and right of this image one can see ripples (possibly fossil dunes) on the crater floor material just above the graben. The floor of Mangala Fossa and the southern crater floor surface also have smaller linear ridges trending from the upper left to lower right. These linear ridges could be either erosional (yardangs) or depositional (dunes) landforms. The lower third of the scene contains a short stubby channel (near the right margin) and lava flow front (lower left). The floor of this channel is fairly smooth with some linear crevasses located along its course. One gets the impression that the channel floor is mantled with some type of indurated material that permits cracks to form in its surface.
The Story
In the Daedalia Plains on Mars, the rim of an old eroded crater rises up, a wreck of its former self (see context image at right). From the rough, choppy crater rim (top of the larger THEMIS image), the terrain descends to the almost smooth crater floor, gouged deeply by a trough, a channel, and the occasional dents of small, scattered craters.
The deep trough running from southwest to northeast across the middle of this image is called "Mangala Fossa." Mangala Fossa is a graben, a land feature created by tectonic processes that worked to create a depression in the landscape. This graben is a little more than 4 miles wide at its maximum, but like most grabens, is much longer than it is wide. You can see from the context image that it runs across much of the width of the crater.
Running southward from the graben (lower right-hand side of the larger THEMIS image) is a branching channel a little over a mile wide. The floor of this channel is fairly smooth with some linear crevasses along its course. These features suggest that the channel floor might be layered with some type of cemented material that permits cracks to form in its surface.
Between the rough crater rim and the depressed graben, tiny crackles on the otherwise smooth surface appear. They might be the ripples of fossil dunes, hardened remains from a more active time. The
Original_Caption_Rel eased_with_Image
(Released 29 May 2002)
The Science
Today's THEMIS release captures Mangala Fossa. Mangala Fossa is a graben, which in geologic terminology translates into a long parallel to semi-parallel fracture or trough. Grabens are dropped or downthrown areas relative to the rocks on either side and these features are generally longer than they are wider. There are numerous dust devil trails seen in this image. In the lower portion of this image several dust devil tracks can be seen cutting across the upper surface then down the short stubby channel and finally back up and over to the adjacent upper surface. Some dust avalanche streaks on slopes are also visible. The rough material in the upper third of the image contains a portion of the rim of a 90 km diameter crater located in Daedalia Planum. The smooth crater floor has a graben (up to 7 km wide) and channel (2 km wide) incised into its surface. In the middle third and right of this image one can see ripples (possibly fossil dunes) on the crater floor material just above the graben. The floor of Mangala Fossa and the southern crater floor surface also have smaller linear ridges trending from the upper left to lower right. These linear ridges could be either erosional (yardangs) or depositional (dunes) landforms. The lower third of the scene contains a short stubby channel (near the right margin) and lava flow front (lower left). The floor of this channel is fairly smooth with some linear crevasses located along its course. One gets the impression that the channel floor is mantled with some type of indurated material that permits cracks to form in its surface.
The Story
In the Daedalia Plains on Mars, the rim of an old eroded crater rises up, a wreck of its former self (see context image at right). From the rough, choppy crater rim (top of the larger THEMIS image), the terrain descends to the almost smooth crater floor, gouged deeply by a trough, a channel, and the occasional dents of small, scattered craters.
The deep trough running from southwest to northeast across the middle of this image is called "Mangala Fossa." Mangala Fossa is a graben, a land feature created by tectonic processes that worked to create a depression in the landscape. This graben is a little more than 4 miles wide at its maximum, but like most grabens, is much longer than it is wide. You can see from the context image that it runs across much of the width of the crater.
Running southward from the graben (lower right-hand side of the larger THEMIS image) is a branching channel a little over a mile wide. The floor of this channel is fairly smooth with some linear crevasses along its course. These features suggest that the channel floor might be layered with some type of cemented material that permits cracks to form in its surface.
Between the rough crater rim and the depressed graben, tiny crackles on the otherwise smooth surface appear. They might be the ripples of fossil dunes, hardened remains from a more active time. The
Original Caption Released with Image
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Original Caption Released with Image:
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floor of Mangala Fossa and the southern crater floor surface also feature small lines that seem to crease the surface. We know that they are ridges on the surface, but how did they form? Were higher surfaces carved away in grooves by the wind and scouring sand, forming ridges called yardangs? Or were dunes deposited on the smooth, lower terrain? No one knows for sure.
Look closely for faint details as well. Do you see the subtle, scalloped pattern that laps at the lower left of the image, almost too muted to be seen? That's the sign of an ancient lava flow that stopped just there. And the shadowy gray streaks? Some are smudges caused by dust avalanches running down the slopes of the channel. Others are the tracks of dust devils that pass across the land, lifting and carrying away brighter dust to reveal the darker surface beneath. For a good example of a dust devil track, check out the faint gray line that cuts across the upper part of the channel, just below the point where it meets the graben.
Original_Caption_Rel eased_with_Image
floor of Mangala Fossa and the southern crater floor surface also feature small lines that seem to crease the surface. We know that they are ridges on the surface, but how did they form? Were higher surfaces carved away in grooves by the wind and scouring sand, forming ridges called yardangs? Or were dunes deposited on the smooth, lower terrain? No one knows for sure.
Look closely for faint details as well. Do you see the subtle, scalloped pattern that laps at the lower left of the image, almost too muted to be seen? That's the sign of an ancient lava flow that stopped just there. And the shadowy gray streaks? Some are smudges caused by dust avalanches running down the slopes of the channel. Others are the tracks of dust devils that pass across the land, lifting and carrying away brighter dust to reveal the darker surface beneath. For a good example of a dust devil track, check out the faint gray line that cuts across the upper part of the channel, just below the point where it meets the graben.
Original Caption Released with Image
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Image Credit:
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NASA/JPL/Arizona State University
Image_Credit
NASA/JPL/Arizona State University
Image Credit
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Produced By:
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Arizona State University
Produced_By
Arizona State University
Produced By
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Mission:
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2001 Mars Odyssey
Mission
2001 Mars Odyssey
Mission
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Spacecraft:
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2001 Mars Odyssey
Spacecraft
2001 Mars Odyssey
Spacecraft
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Target Name:
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Mars
Target_Name
Mars
Target Name
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Is a satellite of:
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Sol (our sun)
Is_a_satellite_of
Sol (our sun)
Is a satellite of
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Instrument:
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Thermal Emission Imaging System
Instrument
Thermal Emission Imaging System
Instrument
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Product Size:
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1231 samples x 3169 lines
Product_Size
1231 samples x 3169 lines
Product Size
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Producer ID:
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20020529A
Producer_ID
20020529A
Producer ID
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facet_what:
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Sun
facet_what
Sun
facet_what
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facet_what:
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Crater
facet_what
Crater
facet_what
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facet_what:
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Mars
facet_what
Mars
facet_what
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facet_what:
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2001 Mars Odyssey
facet_what
2001 Mars Odyssey
facet_what
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facet_what:
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Thermal Emission Imaging System (THEMIS)
facet_what
Thermal Emission Imaging System (THEMIS)
facet_what
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facet_where:
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Mars
facet_where
Mars
facet_where
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facet_where:
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Arizona
facet_where
Arizona
facet_where
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facet_where:
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Jet Propulsion Laboratory (JPL)
facet_where
Jet Propulsion Laboratory (JPL)
facet_where
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facet_when:
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29 May 2002
facet_when
29 May 2002
facet_when
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facet_when_year:
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2002
facet_when_year
2002
facet_when_year
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Image #:
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PIA03815
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UID:
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SPD-PHOTJ-PIA03815
UID
SPD-PHOTJ-PIA03815
UID
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orignial url:
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orignial_url
orignial url
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