3/30/2015
Today’s Class: Robotic Exploration of Mars
Exam 2 Results
March 30, 2015
Homework:
1. Reading: https://en.wikipedia.org/wiki/Mars
2. Meet at Fiske on Wednesday!
• Mean = 83%
• Median = 85%
Astronomy 2020 – Space Astronomy & Exploration
Astronomy 2020 – Space Astronomy & Exploration
Before Spring Break
Clicker Question: What is the longest lasting internal heat
source responsible for geological activity on terrestrial
planets?
• Overview of Solar System
• Tour through the Solar System – Mercury, Venus,
Earth, Mars, Jupiter, Saturn, Uranus, Nepture,
dwarf planets.
• How do robotic spacecraft work?
–
–
–
–
Flybys
Orbiters
Landers
Sample Return
a) Accretion
b) Radioactive decay
c) Sunlight
d) Cosmic rays
• Fiske Planetarium show on Earth as a planet.
Astronomy 2020 – Space Astronomy & Exploration
Astronomy 2020 – Space Astronomy & Exploration
Clicker Question: What is the longest lasting internal heat
source responsible for geological activity on terrestrial
planets?
Today’s Class
a) Accretion
b) Radioactive decay
c) Sunlight
d) Cosmic rays
• NASA’s Goals for understanding Mars
• Search for Water & Life
• The Curiosity Rover
– Goals
– The Gale Crater
– Results so far
With thanks to Professor Brian Hynek for sharing slides!
Astronomy 2020 – Space Astronomy & Exploration
Astronomy 2020 – Space Astronomy & Exploration
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Goals for NASA & Mars
NASA’s goals:
• To advance and communicate scientific knowledge and
understanding of Earth, the Solar System, and the universe.
• To advance human exploration, use, and development of
space.
• To research, develop, verify, and transfer advanced
aeronautics and space technologies
Hubble
View of
Mars
Mars-specific top level goals:
1)
2)
3)
4)
Determine whether life ever arose on Mars
Characterize the climate of Mars
Characterize the geology of Mars
Prepare for human exploration
Astronomy 2020 – Space Astronomy & Exploration
Astronomy 2020 – Space Astronomy & Exploration
Recent Mars Exploration (1990's-present)
NASA’s Exploration Plan:
“Follow the Water”
• Mars Global Surveyor – arrived in 1997 (lasted 10+ years)
– Global imaging, topography, and chemical composition of the surface.
• Mars Odyssey – arrived 2001
LIFE
– Discovered huge regions of ground ice, interesting minerals
• Mars Express (ESA) – arrived 2004
CLIMATE
– Chemical/mineralogical spectrometers, imagery.
• Mars Reconnaissance Orbiter
WATER
– High-resolution stereo imaging (~20 m), subsurface radar
• 2 Mars Exploration Rovers (Spirit & Opportunity) – arrived Jan 2004
GEOLOGY
– 25 cm resolution imaging, sounding radar
• Mars Phoenix Lander (RIP Nov, 2008)
Prepare for Human
Exploration
– Dug down to the ice table at a high latitude site.
• Mars Science Laboratory (Curiosity)
When • Where • Form •
– Launched Nov. 26, 2011, arrived Aug 6, 2012
Amount
* Blue = ongoing operations
Astronomy 2020 – Space Astronomy & Exploration
Astronomy 2020 – Space Astronomy & Exploration
Case for a Warm and Wet Mars I: Rivers
Comparison of Viking and recent data
Hynek and Phillips, 2003
• Dense river valley networks
observed across the ancient
terrains of Mars.
• Viking data suggested
groundwater formation under
cold-dry conditions.
• Recent data provide evidence
for active, long-lived hydrologic
cycle.
10 km
Astronomy 2020 – Space Astronomy & Exploration
Mars river valley
Mars river channel
from Viking data
Mars Global Surveyor data and
newly recognized river valleys
Astronomy 2020 – Space Astronomy & Exploration
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Case for a Warm and Wet Mars II: Deltas
• Deltas require a
standing body of water.
Case for a Warm and Wet Mars II: Deltas
• 22 of deltas have no
local topographic
basin and open to the
northern plains.
• Over 50 known
deltas on Mars.
• These are all at the
same elevation, as
are 15 more nearby
deltas.
• Ages seem to be
coeval with valley
network
formation.
• Suggestive of a
northern ocean on
ancient Mars.
10 km
Di Achille and Hynek, 2010
Astronomy 2020 – Space Astronomy & Exploration
Astronomy 2020 – Space Astronomy & Exploration
Mars 3.7 billion years ago?
2011 Mars Science Laboratory - Curiosity
Launch: Nov. 26, 2011 on an Atlas V rocket
Land: Aug. 6, 2012
Two Earth years of planned operations while
traveling at least 20 km.
Astronomy 2020 – Space Astronomy & Exploration
video
2011 Mars Science Laboratory - Curiosity
Astronomy 2020 – Space Astronomy & Exploration
Video
A most capable robotic geologist!
Launch: Nov. 26, 2011 on an Atlas V rocket
Land: Aug. 6, 2012
Two Earth years of planned operations while
traveling at least 20 km.
Astronomy 2020 – Space Astronomy & Exploration
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Why Gale Crater?
“Sedimentary layers are deposited in a time sequence, with
the oldest on the bottom and the youngest on the top.”
-Nicholas Steno, 17th century
150-km diameter crater
5o S, 222.5 o W
“The processes operating today are the same as
those in the past.”
-James Hutton, 18th century
Example: The Grand Canyon
• 40 distinct rock layers are exposed,
spanning 2 billion years of geologic
history!
• Walking from the Colorado River up
to the rim, one can study what the
local environment was like for
nearly half of the history of the Earth!
The Grand Canyon
More than 5 km of strata are preserved in the central mound
Astronomy 2020 – Space Astronomy & Exploration
Gale Crater
• High diversity of geologic
layers with different
compositions and
depositional conditions
• Stratigraphy records
multiple early Mars
environments in
sequential order
• The findings at Gale
Crater will provide
insights into global
Martian processes:
climate and atmosphere,
geologic processes and
the role of water.
Astronomy 2020 – Space Astronomy & Exploration
Astronomy 2020 – Space Astronomy & Exploration
Gale Crater provides:
1) A long history of deposition by numerous
processes.
2) A significant history of water in the crater.
3) A variable chemistry and mineralogy.
Astronomy 2020 – Space Astronomy & Exploration
Curiosity’s Selfie
NASA/JPLCaltech/MSSS
Astronomy 2020 – Space Astronomy & Exploration
Astronomy 2020 – Space Astronomy & Exploration
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NASA/JPLCaltech/LANL/CNES/IRAP/IAS/L
PGN
6.4 cm deep
NASA/JPL-Caltech/MSSS
NASA/JPL-Caltech/MSSS
NASA/JPL-Caltech/D. Bouic
Arm deployed at John
Klein
Astronomy 2020 – Space Astronomy & Exploration
Sand dunes are also hazardous
Curiosity’s 1.6-cm drill bit, drill and test
holes, and scoop full of acquired sample
Astronomy 2020 – Space Astronomy & Exploration
To Date, Curiosity has:
• Survived on Mars for over 2 Earth years
(all systems operational!)
• Driven > 40 kilometers.
• Characterized stream systems in an alluvial fan.
• Studied mudstones leftover from an ancient
lake.
• Given the materials in this stone, we can infer that the
lake was long-lived and of near-neutral pH.
• Curiosity has clearly demonstrated that Gale
crater was a habitable environment!
Astronomy 2020 – Space Astronomy & Exploration
Astronomy 2020 – Space Astronomy & Exploration
The best is yet to come!
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