A Small "Big Bang"

[DocDiggs]

July 3, 2005
The Big Bang

By DAVID GRINSPOON
Boulder, Colo.

THE future wasn't supposed to be like this. Not for space-age kids like me, growing up enchanted by the Apollo Moon landings and Arthur C. Clarke's "2001: A Space Odyssey." By now we should be living on the Moon and departing in marvelous ships for the outer solar system, while new technologies gradually make life back on Earth more bountiful and harmonious. Instead 2001 and the years since have been marked by terrorism and conflict. Starvation and environmental destruction have not been eradicated or even stemmed. We have, for now, lost the ability to send people to the Moon, let alone Jupiter and beyond, and, for many of us, the future is not as hopeful a place as it once seemed.

Yet tomorrow, we should see one tiny part of Mr. Clarke's grand vision realized - through NASA's Deep Impact mission (an unfortunate echo of a less visionary film). The part of Mr. Clarke's vision I refer to is a small scene in "2001," halfway through the book, that didn't even make the movie. The Saturn-bound scientists, having rounded Mars and now approaching Jupiter, pass close by a small asteroid. They greet this rocky celestial nomad by shooting it with a slug of metal that explodes into the asteroid, leaving a new crater and a brief puff of vapor that soon vanishes into the void.

This Sunday night, if all goes as planned, NASA will finally pull off this same stunt, firing a three-foot-wide 820-pound copper barrel directly into the path of a nine-mile-long, potato-shaped comet by the name of Tempel 1. The two will collide at 23,000 miles an hour while a mother craft photographs the action from what one hopes will be a safe distance, and sends the pictures home to us at the speed of light.

Why? So we can watch what happens. We stand to learn a lot about impact cratering - one of the major forces that has shaped all the worlds of our solar system. We will also have the chance to peer into the newly formed crater and observe the ice and vapor blasted back into space, thereby learning what lies within this frigid little world. When I describe this mission to people outside the community of space scientists and enthusiasts, it receives mixed reactions. Some feel that this is a fine hello to a new world, blasting away at it just to see what happens, like greeting a stranger by shooting first and asking questions later. A lawsuit has even been filed in a Russian court by a 45-year-old mother of two in Moscow, demanding that the mission be called off on the basis of its environmental and spiritual, well, impact.

This legal action seems even more certainly doomed than the spacecraft itself (which may miss its target). Yet perhaps it does epitomize the concerns of many who wonder why we would do such a thing. Aren't we going too far to satisfy our curiosity here, acting like cruel, senseless boys blowing up frogs for the fun of it?

Um, no. This explosion is not going to hurt anyone or anything.

Here's an analogy. You would be justifiably concerned if, in order to learn about shorelines, some scientist decided to dig up your favorite beach. But you wouldn't object if she took a few grains of sand to study. There are something like one trillion comets larger than one mile in diameter, several hundred for each human on Earth, in this solar system alone, and countless more in the wider universe. So even if we destroyed Tempel 1 entirely, we would not be making a dent in the cometary sandbox.

What's more, this mission will not demolish the comet, alter its course, or otherwise affect the cosmic scheme. Comets collide with other celestial objects all the time. The only thing extraordinary about this particular impact is that we engineered it. Deep Impact will simply make one more small hole in an object that, like all planets large and small, has been repeatedly dinged by colliding space debris since our solar system's origin 4.6 billion years ago.

It is those dusky beginnings that this experiment can illuminate. Beneath the dirty ice crust of a comet like Tempel 1 is material that has been in deep freeze since the birth of our solar system. Mixed into this timeless frozen treat are organic molecules like those that seeded the young Earth with raw materials for making life. This ice may hold some buried chapters of the story of our origin.

As H. G. Wells, the Arthur C. Clarke of the paleoindustrial age, once wrote: "There is no way back into the past. The choice is the Universe - or nothing." It has been said that the dinosaurs ultimately got snuffed because they lacked a space program. Sooner or later a killer comet will again cross Earth's path, threatening all life. Only next time, armed with knowledge about comets and space engineering, life on Earth will have a fighting chance.

Someday, some of our descendants may decide to declare independence from this planet, seeking a more perfect union with the cosmos from which we spring. If so, then our current, tentative efforts in space may carry evolutionary significance equal to life's first forays from the oceans onto land.

Given the recent reckless talk from the Department of Defense about introducing offensive weapons into space, Deep Impact will probably be seen in some quarters as more evidence of American aggression.

In reality, it is the opposite - a peaceful gift from our nation to the world. Deep Impact is pure exploration. In this sense, we have evolved. Unlike Apollo, which was meant in part as a cold war threat to the Russians, Deep Impact really is for all humankind: it could further our understanding of where we all came from.

Of course, explosions are cool (when they aren't hurting anyone). They're also often quite beautiful. Why, after all, do we love to watch fireworks? The flash of Deep Impact exploding into Tempel 1 may be visible from Earth through telescopes (and even, just possibly, to the naked eye, but not from the Eastern United States) at 1:52 a.m. Eastern time on July 4, above the bright star Spica, and to the left of Jupiter. Public events, showing live images from the world's best telescopes and, 10 minutes later, the first pictures from Deep Impact itself, are planned at many science museums. If successful, first-ever images of the approaching comet, the brilliant impact, the new crater and the receding icy nucleus will be seen soon thereafter. The scientific analysis that reveals the true meaning will be slower in coming, but once it arrives, the knowledge will be here as long as we are.

David Grinspoon, a planetary scientist at the Southwest Research Institute, is the author of "Lonely Planets: The Natural Philosophy of Alien Life."

[Woodmonkey]

I don't know about anyone else, but I think this is exciting.

[Snowden]

It was set for tonight! I can't wait to find out what happened; what it looked like!

[Jacklou59]

Have To Wat To Find Out Morei

[Caldric]

Great post Doc. I like that writer and how he uses our worse to show our best. He is pretty good.

Anyway I posted on the results of the impact. I watched in on NASA TV on the web was cool stuff. I did not even expect the size of the explosion, I think it even suprised Nasa. Perhaps the comet is not as dense as they expected.

NASA TV http://www.nasa.gov/multimedia/nasatv/index.html

[DocDiggs]

Originally Posted by Caldric

Great post Doc. I like that writer and how he uses our worse to show our best. He is pretty good.

Anyway I posted on the results of the impact. I watched in on NASA TV on the web was cool stuff. I did not even expect the size of the explosion, I think it even suprised Nasa. Perhaps the comet is not as dense as they expected.

NASA TV http://www.nasa.gov/multimedia/nasatv/index.html

It's gonna be fantastic to see the data they get from this! Thanks for the link.

[filthybeast]

Drat I thought we were talking about a Nooner here.