Friday, April 24, 2009

Pathfinder & Phoenix


If by some odd circumstance you happened to be standing in the valley of Ares Vallis, in the Chryse Planitia region of the planet Mars on the fourth of July, in the year 1997, you might have seen in the dusty, yellowish brown sky a distant fireball descending slowly towards your position. Don't worry, the blaze would soon disappear. But in a very few moments you would be astounded to see a huge beach ball bouncing over the Martian surface, slowly losing energy as its bounces became less frequent, the ball slowly coming to rest on the cold, airless surface. If that wasn't unusual enough, as you approached the ball like object you would see it deflate, and hidden inside a metal object appears, opening up like a three petaled flower, folding back until the petals found their resting place on the ground. The petals being solar panels that began to collect and utilize the energy supplied from the distant sun.
This is the Pathfinder spacecraft. If you came back the next Martian day you would see another astounding thing. A little robot descending off a ramp from Pathfinder, scooting over the surface, looking around for interesting objects to examine. How cute. This would be the Sojourner rover.
Attached to the body of the Pathfinder, you might not notice because it's rather small, resides a circular disk. It's sort of a DVD. My name is on it.
I've been a member of the Planetary Society off and on nearly since its inception in 1980. It was founded by Carl Sagan, Bruce Murray, and Louis Friedman, and has grown into the largest grass roots, science (especially astronomy) advocacy organization in the world, with members in over 125 countries. The Astronomer Neil deGrasse, who seems to have filled the void left vacant when Dr. Sagan died, of the most noted popularizer of science, is currently the society's president. The society is dedicated to the exploration of the solar system, near earth objects (asteroids that could fall on our planet and go boom), and the search for extraterrestrial life.
We carry out our own projects. In June of 2005 we launched the Cosmos 1 spacecraft to test the feasibility of solar sailing (as opposed to solar surfing), attempting to utilize the pressure of sunlight to propel spacecraft. The launch vehicle failed though, and we're trying to start again.
These things tend to be rather expensive.
We do all kinds of things. We will be sending a collection of living organisms on a three year trip to Phobos, one of the two Martian moons, in order to gain a better understanding of the robust nature of life, and its ability, or not, to move between the planets ("transpermia" hypothesis). We look and study our own planet, in comparison to the other planets in the solar system that have experienced cataclysmic climate change (Mars losing its atmosphere, Venus the victim of a runaway greenhouse effect, with a surface temperature of 900 degrees Fahrenheit, an extraordinary example of global warming). You can virtually drive a Mars rover at the societies web site, and we've aggressively lobbied Congress to keep NASA and space science projects well funded during the last eight years as the Bush administration declared war on science and drastically cut funds. We do many other interesting things as well.
The Pathfinder and Sojourner experiments were a complete success, lasting two months longer than the one month scheduled for activity. It has since been renamed the Carl Sagan Memorial Station, and can be seen from orbit.
On May 25th of last year, the Phoenix robotic spacecraft touched down in the Green Valley of the Vastitas Borealis lowland region, just south of the northern polar ice cap. It was photographed during its descent by the Mars Orbiter, making it the first spacecraft to be photographed while landing on another planet. Its mission was to study the geological history of water, and to evaluate past or potential planetary habitability in the ice/soil boundary. It was designed to last about three months before succumbing to the Martian winter, but like Pathfinder, it to lasted two months longer than expected.
It to carried a silica DVD with the names of all of the Planetary Societies members etched upon it, including mine. I have a certificate to prove it (I showed it to my lovely case manager, Erin, earlier today at Movie Day ("The Mexican," Erin says it is her new favorite movie). She said she was jealous, and was going to get a star one day. I'm not quite sure what she meant by that, but we'll see if we can get her one. Her birthday is coming up).
The image at the top of this post "shows the DVD provided by The Planetary Society to the Phoenix mission, which contains 250,000 names of people who signed up to send their names to Mars. It also contains "Visions of Mars," messages to future Martian explorers, science fiction stories and art inspired by the Red Planet. The DVD is mounted on the deck of the lander, which sits about one meter above the Martian surface, visible in the background.
The first library on Mars – contains materials that represent 20 nations and cultures. Visions of Mars includes works by The Planetary Society's co-founder Carl Sagan, Isaac Asimov, Ray Bradbury, Kim Stanley Robinson, Arthur C. Clarke, Percival Lowell and many more."
Unlike the moon, Mars has a thin atmosphere of carbon dioxide, about 1% of the Earth's at sea level. Rarely the entire planet experiences global dust storms, so erosion does take place. The DVDs contained on the Pathfinder and Phoenix spacecraft will probably last up to 500 years before being worn away.
That's okay. We'll just keep sending them up.

No comments:

Post a Comment