Projects: Space Information
The Planetary Report
Volume XXIII, Number 3, May/June 2003
Credit: NASA / JPL / Malin Space Science Systems |
On the Cover
In less than a year, Mars will play host to an international
party of visitors. The European Space Agency's Mars Express (with the
British Beagle 2 lander) is scheduled to get to the Red Planet in late December
2003 or early January 2004—the same month that NASA's twin Mars Exploration
Rovers and Japan's Nozomi will arrive. Here, Mars Global Surveyor's Mars
Orbiter Camera reveals our ruddy neighbor's north polar cap as it appeared
in May 2002. Seasonal dust storms swirl around the cap's edge in this
mosaic of daily global images.
From The Editor
We are entering the year of Mars. It
begins not with the calendar year
but with the launches of four spacecraft in
June: the European Space Agency’s Mars
Express, carrying the British Beagle 2 lander,
and the twin Mars Exploration Rovers.
Already on its way is the Japanese Nozomi
orbiter. In Earth’s early winter, the spacecraft
will arrive at their destination, where
they will join the Mars Global Surveyor
and Mars Odyssey, already in orbit. Never
before have so many spacecraft converged
on one planet at the same time.
The reason for all this is simple geometry.
In August, Mars reaches opposition,
the point in its orbit directly opposite Earth
from the Sun. Spacecraft can then travel
between Earth and Mars using the least
amount of fuel. This is too good an opportunity
to pass up.
The Planetary Society also is taking advantage in every way we can. Mars Watch
is under way, encouraging people around the world to get out and view the Red
Planet at its brightest. Our Red Rover Goes to Mars students will join NASA’s
rover team. And when the first rover sets down on Mars, we will hold Planetfest ’04,
on January 2 to 4, to celebrate all this exploration and more.
This is a great time for Society members. Each one can participate in some
way in each of these events. Check our website and watch these pages to learn
how you can personally experience the year of Mars.
— Charlene M. Anderson
Features
A Place to Call Home: Selecting the Next Mars Landing Sites
The trickiest
part of any mission to the surface of another world is the landing. First,
the spacecraft must be targeted to the right spot. Next, it must be angled
to hit the atmosphere just right, so that its heat shield can protect it
from burning up during entry. Then, it must be braked so it doesn’t land
with a crash. Thrusters, airbags, or some other device must cushion its
ultimate contact with the planet. Finally, one hopes it is not shredded
or upturned by the treacherous alien terrain. To avoid the latter disaster,
scientists and engineers on the Mars Exploration Rover team have worked
for months to select sites on Mars safe enough to land on—and
exciting enough to provide valuable science. Emily Lakdawalla, science
and technology coordinator for The Planetary Society, attended many of the meetings
and here reports on the results.
Mars Infrared
Human eyes—and cameras that operate
with visible light—see only
in a tiny region of the electromagnetic spectrum. For geologists, this
can be a disadvantage. Simply by looking at a rock, it’s very hard to see
what minerals it contains. When the rock is on another planet and the geologist
is restricted to looking through robotic eyes orbiting high above the surface,
the problem is greatly magnified. A way around these problems is to build
instruments that see in different regions of the spectrum. The infrared is
a particularly useful region for determining mineral composition, and geologists
have been gleeful over the data returned by two infrared instruments now orbiting
Mars, one on Mars Global Surveyor and the other on Mars Odyssey. Phil
Christensen and Matthew Shindell share here the exciting discoveries with Society members.
Departments
Members’ Dialogue
We Make It Happen!
Questions and Answers
Society News
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