Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, June 30, 1994 TAG: 9407020009
SECTION: EXTRA PAGE: 1 EDITION: METRO
SOURCE: Joel Achenbach
DATELINE: LENGTH: Long
A: New Jersey, for example. Surely that's harsher than your average crater on Mars.
Seriously, there's a feast-or-famine quality to life in our solar system. Our planet is literally crawling with it, from deep sea vents to subterranean rock in Antarctica. Meanwhile every other planet or moon in the solar system has failed to get its act together.
Life on Earth is ubiquitous because it's adaptive. With enough time it can get suited to anything. We should remember that the proverbial primordial soup (or is it the primordial proverbial soup?) wasn't a harsh environment at all. It was rich in complex molecules, warm, dynamic - pretty cushy if you were a young amino acid in a hurry.
Originally things were pretty nice on Venus and Mars too.
``Venus, Earth and Mars probably started off with fairly similar climates,'' says Chris McKay, a NASA research scientist at Moffett Field, Calif.
But Venus never had a chance. It is too close to the sun. The heat boiled off the water. Then solar radiation broke down the water molecules in the upper atmosphere, and the hydrogen escaped into space. The carbon dioxide molecule is made of sturdier stuff. With no rain to precipitate it, it accumulated in Venus' atmosphere. Hence, a runaway greenhouse effect. Hence, surface temperatures of 900 degrees F. Hence, no bunnies.
Mars is the big mystery. About 3.5 billion years ago it was warm and wet, and liquid water flowed across the surface. McKay thinks there may have been life. ``It could have had the buildup of multicellular organisms, dinosaurs, people, everything,'' he says.
So why did Mars go belly-up? Size, probably. Mars is not nearly as large as Earth. Without a lot of gravity, it had a hard time keeping its atmosphere from evaporating into space.
Most importantly, it lacked tectonic forces. On Earth, we have colliding tectonic plates, which seems like boring geology but is crucial to life. The carbon in atmospheric CO2 dissolves in water and forms calcium carbonate, piling up on the bottom of lakes and the ocean floor. But some of the Earth's crust gets suducted under adjacent tectonic plates, is heated, and finally is spewed out from volcanoes, with the vaporized carbon rejoining the atmosphere.
Without this kind of tectonic dynamism, Mars couldn't recycle its carbon. The atmospheric carbon dioxide chemically reacted with surface elements. Gradually the CO2 in the air diminished. The greenhouse effect lessened. Mars got colder, and finally the surface water evaporated or froze.
There may be liquid water under the surface of Mars, but there are not likely to be Martian mole-people. And although there are scenarios in which life may have formed in the mild upper atmosphere of Venus or in liquid water under the frozen surface of the Jovian moon Europa or beneath the hazy cloud-cover of the Saturnian moon Titan, that's probably wishful thinking.
Cold, dead and desolate are the norms in this universe. The way we see it, life is lucky to be alive.
The mailbag:
We got angry phone calls and letters from what certainly seemed like a significant percentage of the world's Catholics regarding our column on why Catholics put so much emphasis on the Virgin Mary.
We were surprised, because the column did not attack Catholicism or Marian devotion, and the flippancy quotient was shockingly low by our standards - not a single transubstantiation joke or anything! So why'd people get so mad at us?
For one thing, people strongly objected to a line in our column in which we said that ``traditionally'' Catholics don't pray directly to God but rather to saints to intercede on their behalf. That was sloppy on our part: While it's certainly true that intercessory prayers are a traditional element of Catholicism, Catholics have always prayed directly to God as well.
We called Father James Wiseman, a Benedictine monk who teaches at Catholic University in Washington, and he said, perhaps as an act of charity, ``Even though your phraseology was wrong, you were onto something.'' He said the Protestant Reformation included a belief that ``the whole business of praying through the saints was wrong.'' Wiseman also noted that when the mass was still said in Latin, many worshippers could not possibly follow the prayers, and thus would pray the Rosary, much of which is directed to Mary.
One Catholic caller said that by saying Catholics didn't pray directly to God we were repeating a Protestant slander against Catholicism. One letter writer asked, ``Been running around with Jimmy Swaggart again?'' There is a sense out there among Catholics that they are under attack, and they are alert to Catholic-bashing.
Clearly our column stumbled onto, and across, a minefield.
But we must end with a warning: We'll do religion again in this space. The Why column must be fearless even at the risk of damnation. Many callers asked something on the order of, ``Would you dare write a column like that about Jews or Moslems or Buddhists?'' Indeed we would.
Washington Post Writers Group
by CNB