GEO 330 Lecture 26: Landing Sites -- Surface Properties and Processes - 2
14 May 2018
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Identical rovers sent to Meridiani Planum and Gusev Crater
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Search for evidence of water -- hydrothermal, evaporite ,or sedimentary deposits
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Panoramic Cameras (Pancam)
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Miniature Thermal Emission Spectrometer (Mini-TES)
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Microscopic Imager (MI)
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Mossbauer Spectrometer (MB)
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Alpha-Particle X-ray Spectrometer (APXS)
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Rock Abrasion Tool (RAT)
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Magnets
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Scientific instruments:
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Mars Exploration Rovers
Gusev is a 160km Noachian crater near the plains/highlands boundary
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Thought to have once contained a lake -- southern wall breached by Ma'adim Vallis
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Later examination of low hills found extensive evidence for aqueous alteration
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Bottom of Gusev found to contain volcanic rocks rather than sedimentary deposits
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Spirit at Gusev Crater
Starts 1000 km to the south, before ending in Gusev crater
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Over most of its length, it is 8-10 km wide and 1 km deep
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Abrupt start and large size is similar to outflow channels, but it also has numerous
tributaries
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Formed as a result of massive drainage of Noachian lake?
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Ma’adim Vallis, one of the largest valleys on Mars, combines some characteristics of a valley
network and an outflow channel
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If hills are remnants of a delta, water level must have been~300 m above present day crater
floor
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Breach point of Gusev contains large flat-topped hills interpreted as a delta deposit
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Apollinaris Patera lies just to the north, and may have been a source of volcanic ash deposits
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Remnants of the Medussa Fossae Formation to the northeast may be present in the eastern
part of Gusev
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Volcanic intrusions, wind-blown sediment, and impact ejecta may also contribute to crater
floor material
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Rover sent to look for lake sediments, but a variety of materials are probably of diverse origin
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Several filled-in craters on the Gusev floor suggest that a large amount of time elapsed between
the formation of Gusev and the deposition of all the floor deposits
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Gusev Crater -- Geologic Context
Spirit landed near the center of Gusev ~20km to the west of Thira rim
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Landing site characterized by relatively flat, rocky plains -- from the ground, site does not look too
dissimilar from Viking or Pathfinder sites
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Rover characterized rocks in vicinity of lander and then moved 300m NE to rim of Bonneville
crater
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From Bonneville, rover travelled 2.6km to Columbia Hills, where it explored until 2010
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Plains are a rocky surface crossed by poorly defined ridges and numerous shallow hollows that are
probably secondary craters
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Between rocks, surface is covered with light-toned reddish regolith
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Gusev Crater -- Plains
Landing Sites -- Surface Properties and Processes
Thursday, May 3, 2018
1:45 PM
GEO 330 Page 1
Document Summary
Identical rovers sent to meridiani planum and gusev crater. Search for evidence of water -- hydrothermal, evaporite ,or sedimentary deposits. Gusev is a 160km noachian crater near the plains/highlands boundary. Thought to have once contained a lake -- southern wall breached by ma"adim vallis. Bottom of gusev found to contain volcanic rocks rather than sedimentary deposits. Later examination of low hills found extensive evidence for aqueous alteration. Ma"adi(cid:373) vallis, o(cid:374)e of the largest (cid:448)alleys o(cid:374) mars, (cid:272)o(cid:373)(cid:271)i(cid:374)es so(cid:373)e (cid:272)hara(cid:272)teristi(cid:272)s of a (cid:448)alley network and an outflow channel. Starts 1000 km to the south, before ending in gusev crater. Over most of its length, it is 8-10 km wide and 1 km deep. Abrupt start and large size is similar to outflow channels, but it also has numerous tributaries. Breach point of gusev contains large flat-topped hills interpreted as a delta deposit. If hills are remnants of a delta, water level must have been~300 m above present day crater floor.
