USA TODAY, MARCH 24, 2004, LIFE, 1D
What’s the
next frontier
NASA’s planned missions include:
Sun
Venus
Mercury
Source: NASA
(not to scale)
Earth
Messenger
Launch date: May 11
Orbit begins: July 2009
Uranus
Mars
Mars Reconnaissance Orbiter
Launch date: August 2005
Arrival: March 2006
Jupiter
Jupiter Icy Moons Orbiter
Launch date: 2011
Saturn
Cassini
Launch date: October 1997
Orbit begins: July 1
Neptune
Pluto
New Horizons
Launch date: January 2006
Flyby: July 2015
By Web Bryant, USA TODAY
NASA's Mars gamble pays off
Part 1
'Following the water'
paves way for biggest
find of all: Life
ing spacecraft of ice under Mars' surface and at the poles, the discovery
that water once flowed on the planet
makes it seem much more likely that
President Bush's goal of sending astronauts there will be realized.
By Dan Vergano
Some people go to Las Vegas to gamble. NASA went to Mars.
And now the space agency appears
to have hit the jackpot by finding evidence of water on the Red Planet.
Scientists announced Tuesday that one
of its exploratory rovers is parked on
the shoreline of what once was a salty
Martian sea.
It is a sorely needed victory, one that
quiets critics who have taken a dim
view of NASA since the shuttle
Columbia disintegrated in the skies
over Texas last year. NASA was blamed
for the disaster, which killed seven
astronauts; its operations and even its
culture were called into question.
Now, the Mars twin rovers — the
mobile
geology
labs
dubbed
Opportunity and Spirit — have revived
NASA's reputation and vindicated its
exploration strategy.
Paired with the detection by orbit-
"Human exploration and ultimate
colonization of Mars will depend on
accessibility to one resource: water,"
writes space scientist Timothy Titus of
the U.S. Geologic Survey in Flagstaff,
Ariz., in Nature magazine. "For life on
Mars, water is the elixir."
In beating the odds — two-thirds of
past Mars missions ended in failure —
NASA's $820 million twin-rover mission ran a gantlet of pitfalls and risks:
u NASA first debated whether to
send the roving geology labs or to stick
with tried-and-true orbiters. Both
kinds of missions were considered to
have equal scientific merit. The perils
of descending through the Martian
atmosphere made the rovers a riskier
proposition, but they offered a closer
look at this most foreign of lands. The
rovers eventually won out at NASA
headquarters in 2000.
u NASA's Jet Propulsion Laboratory
1
team built and launched the rovers in
three grueling years that left the staff
exhausted.
u The European Space Agency
pulled ahead with the launch in June of
Beagle 2, its Mars lander. Then, just as
NASA was preparing for a nearly identical landing, the European mission
failed with the disappearance of Beagle
2. Its fate remains unknown.
u The rovers' complicated landing
system of heat shields, parachutes,
braking rockets and airbags had to take
the technology to the edge of its capabilities to be successful. It worked
flawlessly.
Right place, right time
It helped that Opportunity landed
perfectly in a crater on the Oklahomasized Meridiani Planum region, which
is lined with sedimentary rock.
"Meridiani has offered far more than
expected — right at the lander's feet,"
says Melissa Lane of the Planetary
Sciences Institute in Tucson. "It was a
hole-in-one."
In 2002, she was lead author of the
Journal of Geophysical Research report
that identified Meridiani Planum as a
possible lake bed of the past. The composition of a bedrock outcrop confirms
that water once soaked the rock layers,
says rover mission chief scientist Steve
Squyres of Cornell University.
The landing site for Spirit, the
Connecticut-sized Gusev Crater on the
Mars research went into hibernation
after the 1976 Viking mission landings.
Designed to detect life, the landers
found no organic molecules in samples
of the soil.
Then more recent findings reignited
NASA's interest, such as the discovery
four years ago by the orbiting Mars
Global Surveyor of gullies that looked
as if they had been carved by water.
NASA’s Mars gamble pays off
Article continued in next lesson.
VOCABULARY
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Discussion
other side of Mars, was chosen because
it was expected to reveal more signs of
having been a lake bed. It turned out
that any such deposits appear to have
been buried by lava, although Spirit did
find some mineral evidence of water.
uWhat impact has the Mars expedition had on NASA’s reputation?
uWhy did NASA choose Gusev Crater as the landing site for Spirit?
uWhat made sending rovers to the planet such a risky proposition?
atmosphere
sedimentary rock
bedrock
mineral
organic
uWhy was the landing of Opportunity a “hole in one”?
A
A
A
A ctivity
In small groups, you will be creating a scale model of our solar system using balls, newspaper, papier-mâché, or another material of your choice. Your model (at maximum) should be able to fit on a
table inside your classroom. First, refer to the measurements listed below, and decide on an appropriate scale. Then, convert each diameter and distance to the measurement you will use for your
model. Finally, use your conversions to construct each planet and the sun so that they represent
the real objects. Using wire, string, etc., space the planets the correct distance from the sun. Ask
another group to examine your model and determine the scale on which it is based.
The scale we have chosen is ______________________________ =______________________________.
Planet
Earth
Diameter (miles)
Scale
Distance from sun (miles)
7,926
92,897,000
88,846
484,000,000
Mars
4,220
142,000,000
Mercury
3,032
35,983,000
Neptune
34,504
2,800,000,000
1,485
3,670,000,000
Saturn
74,898
887,000,000
Uranus
31,763
1,780,000,000
7,521
67,200,000
Jupiter
Pluto
Venus
The sun
Scale
863,706
Source: www.jpl.nasa.gov and Encarta
Numbers have been rounded.
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