Space Travel: Pros and Cons

This is actually a presentation that we did at school carried out between two people. One is a spokesman for space travel, the other a sceptic who doesn't like the idea at all.

I put it on my website and since then it has been published in a book titled "Pro/Con" (full details at end).

Proposed Pro 1: Survival of the species

SPOKESMAN: At the moment, the human species is intimately dependent on the fragile ecosystem of the planet Earth. This ecosystem is vulnerable to dramatic change, which would be disastrous and probably deadly to human life on Earth. Three example mechanisms for such change are: Nuclear War, Asteroid or Comet impact, and gradual atmospheric change. We can hope to hold off the first cause for as long as we can, but we are helpless against the second two. If we cannot save ourselves against possible disastrous change, we must break free of the fragile ecosystem. We must establish a human presence in space to avoid total extinction in the event of harm to our planet.

SCEPTIC: I agree that asteroids and nuclear war would present a global change quick and severe enough to wipe out the human species. But isn't gradual atmospheric change the kind of thing that species evolve with anyway?

SPOKESMAN: Yes, but only a fraction of the species survive this evolution. If the ecosystem changes, the only species that survive are those already adapted to live in the new conditions. It is not the case that each life form would suddenly change to meet the new conditions. That is not how evolution works. What would happen would be that the only creatures that survive are those already capable of coping with the new conditions by their nature. In this way, evolution selects against all creatures not capable of coping with current conditions.

SCEPTIC: But look at the amount of change that has been brought about to the atmosphere in the last couple of centuries by us. Fossil Fuel burning springs to mind as an example. If we can affect the atmosphere so dramatically, surely we can change it for the good? Also, is it not possible to deflect or destroy any "cosmic bullets" nature might fire at us?

SPOKESMAN: I agree - we have to some extent changed the composition of our atmosphere. But bringing about change for the good is much harder than just disrupting the ecosystem, because it requires a very specific change - the right change - to be brought about. The ecosystem is a very complicated system, far more complicated than the weather, for example - and weather predictions are only at all reliable over a time scale of about three days. The only change we can bring about with any confidence is to find out what changes have been brought about, and lessen the mechanism that brings about such change. An example is the reduction in the usage of CFC?s in domestic products.
Asteroid impacts are even harder to deal with. It is true that an asteroid the size of Texas, like that in the film "Armageddon," would not go undetected. The biggest known asteroid, Ceres, is less than 1000 km in diameter. Texas is about 1400 km across, so if there were a Texas - sized asteroid coming anywhere near the Earth, we would know about it! The bad news is that an asteroid the size of Texas would be very hard to deflect - rather than one bomb, an asteroid 1000 km across would require about a hundred billion megatons to deflect it. Anyone want to carry a hundred billion nukes into orbit?

For example, imagine an asteroid about 200m across, travelling at about 22 km / sec when it hits. If it hit in the ocean, this asteroid would create a tidal wave 5m high. By the time it reached a land mass, with shallower water around it, the wave would be about 200 metres high, travelling at 450 miles per hour, smashing into coastal areas with devastating force. With the best detection equipment available today, the asteroid would not be detected until about eight seconds before impact. Eight seconds!

Another example is the Barringer meteor crater in Arizona. The crater is about a mile wide, but the asteroid itself was about 50m across, which is today completely undetectable. Now it is theoretically possible that with advances in technology and a serious detection programme, such meteors might be detected far enough away to deflect before impacting the Earth.

SCEPTIC: But that particular example of space technology is too dangerous to be developed. If we can deflect an asteroid away from the Earth, then by a miscalculation, or deliberate plan, one could be deflected towards the Earth. The technology of deflection would precipitate the exact catastrophe the space scientists purport to avoid.

SPOKESMAN: Exactly my point. Deflection is too unreliable - we are helpless in the face of asteroid impacts. We need to get some of us out of the way. This way, if - or rather when - the next big asteroid hits and changes the biosphere irrevocably, the human race wont become extinct. It is illustrative to look at the survival of animals on the Earth. Those animals that spread to many habitats have thrived, while those that remained confined to their original small habitat have either died out or are endangered.

SCEPTIC: You said "if - or rather when - the next big asteroid hits." I believe catastrophic impacts occur every hundred million years, and the last one took place roughly 65 million years ago, according to current scientific theory. We aren't due for another hit like that for another 35 million years, so we're safe for the foreseeable future.

SPOKESMAN: You're correct - catastrophic impacts are expected to occur roughly once every hundred million years. But this is an average figure. What this is saying is that a catastrophic impact should happen at least once in the next hundred million years. It tells us about the rate of impact, not the timing of impacts. It might not happen until around the year 40 million A.D. But it might take place next year. Imagine rolling an unloaded dice twelve times. You should get a six at least twice in twelve throws. But the timing of the throwing of the sixes is random. We are always in the firing line!

Proposed Con 1: It's expensive to travel in space.

SCEPTIC: We're always being told about the many ways the space program is said to benefit humanity. But at what cost? From time to time, rockets fail on launch - witness the hundreds of millions of dollars wasted whenever a rocket blows up on launch, or the great human cost of the challenger disaster. I ask myself: are there more direct ways to benefit society with this money? I put it to you that space exploration is a waste of money.

SPOKESMAN: Of course space exploration is expensive. That's because it's very, very hard. It requires very complex and reliable technology and a big support infrastructure to be at all successful. It is true that the money could be spent directly on helping to fix the problems of the human species. For example, the price tag for a manned mission to Mars weighs in at $50 billion. Think what could be done with that money if spent on the education system, for example. Spending money on space exploration must be justified when there are still problems on Earth.

But whether space exploration is a waste of money is, I think, open to debate. To what do we compare the asking price of the Universe? Don't forget the successes of the space programme. The Voyager probes, for example, have cost the average American taxpayer roughly ten cents per year since their launch in 1977. The probes were designed to last three years, enough to explore the planets Jupiter and Saturn. Voyager 2 went on to encounter the planets Uranus and Neptune, with an accuracy in navigation similar to throwing a pin through the eye of a needle 50 miles away. The Voyager probes returned the equivalent of 100,000 encyclopaedia volumes of new information and visions of the solar system, operating for some six times their projected design lifetimes. The Voyagers were spectacular successes.

And are we really talking about huge amounts of money here? The $200 million spent on the Mars Pathfinder mission, for example, is a large amount of money. But compare this with the $2.4 billion spent in one year - 1982 - on the development of the MX cruise missile programme. And this was $2.4 billion fifteen years before Pathfinder was launched, meaning this is an underestimate of the cost of the missile in today's money. I think it is hard to argue that the MX missile has brought more benefit to humanity than the Mars Pathfinder mission, yet it cost a lot more.

It is true that space travel requires lots of money, a fact its opponents are always quick to point out to the public. What is often forgotten is the scale of other expenditures. Let's look at the USA, which spends more than any other country on space exploration. In 1999, the US plans to spend about $270 billion on defence, $200 billion on Medicare and about $400 billion on social security. By comparison, the science budget is about $70 billion, from non - industrial sources, of which $14 billion is to be spent on NASA. In other words, the US space budget is about one twentieth the amount spent on defence, and about one twenty - ninth that spent on social security.

SCEPTIC: Okay, okay - we all know that a lot of money is spent by the US government - what's your point? That money goes towards defending the country from aggressors and looking after the people!

SPOKESMAN: Well, I assume the reason you would cut the space budget would be to allow the money currently spent on space exploration to be spent on solving more down - to - Earth problems. Such as eliminating cancer, or providing better education. This is a very laudable goal. But I think you have the wrong target. Don't forget, the space program in America grew originally out of the military ballistics programme. Were the space budget to be cut, I find it much more likely that the majority of the money would get redirected back to the military, resulting in a larger gap between defence spending and domestic spending. In other words, cutting the space programme would do more harm than good to the American people. We should be able to fund both space exploration and domestic programmes, such as education and health. If you're looking for a few billion dollars to spend on education, why take a quarter off the space budget, when you can take one percent of the defence budget?

SCEPTIC: Because defence programmes do more than just send eight people round the Earth a few times! Look at Apollo. Billions of dollars spent, many lives lost in tests and development, and only one scientist actually got to the moon. The entire space race was politically motivated muscle - flexing by the superpowers, at the expense of the taxpayer.

SPOKESMAN: Don't forget that the manned space flight programme is only one part of the space programme, though it does take over a third of the space budget. Manned space flight is a far harder challenge than unmanned flight - humans require much more onboard support than computers! This means that manned space flight is much more expensive than unmanned. This is true for all space programmes, not just the American space programme we have been using as an example.

I have a much harder time justifying the expense of manned space flight on financial grounds than advocating the space programme in general. I don't have a problem advocating one attack helicopter's worth of money to fully fund a SETI programme, or asking for the same amount to build a robot that will peel a little more away from the mystery of the solar system. But asking for a hundred million dollars to do a manned mission that could be done better and more cheaply by an unmanned rocket - such as the 1986 Challenger mission - is harder to justify, in my opinion. It is true that there are some missions that could only be performed by human operators - such as the Hubble repair mission. But whether the majority of the manned missions are worth risking lives over is I think more debatable. Of course, the manned space flight programme represents the first small steps in a much longer term process. I do not think it is clear that we're ready to take those steps yet. But the unmanned space programme is one of the finest achievements of the last 2000 years of technology, representing value for money that is the envy of most other human endeavours.

SCEPTIC: Then you admit that if we're not ready to do manned space flight, we should axe it on financial grounds?

SPOKESMAN: If it were possible to take out just the money for the unnecessary manned missions, then yes. Two factors stand in the way of this proposal. Firstly, if the unnecessary manned missions are axed, it will make it harder for the necessary manned missions to be carried out successfully. The infrastructure and experience won't be there. The second factor is that the manned space flight programme is the financial - and to a large extent political - reason for the existence of the space programme in the first place. Though by far the greatest scientific returns come from unmanned missions, those in office and the public see the manned programme as the face of space exploration. NASA is a servant of the public, as it must be, and is legislated on by those in power - not by scientists. Were the manned programme to be axed, NASA would no longer be serving the public demand and would actually have more trouble surviving. So I think that it would be a nice idea to trim off the budget associated with unnecessary manned missions, but I also think it is an impossible idea to carry out. NASA?s fortunes rise and fall with those of the manned space programme.
But I really don't think the space programme is a waste of money. In fact, I think that $14 billion a year is a very reasonable price for the Universe! And it doesn't have to be paid at the cost of education or health.

SCEPTIC: Well, I don't think we're ready for the Universe yet.

Proposed Pro 2: Space Exploration helps science education

SPOKESMAN: One benefit space travel brings mankind, which is very much down - to - Earth, is that it furthers education. Once Apollo went up, for example, the number of young people pursuing a career in science increased. Space exploration inspires people to learn about science, and generates demand for better facilities.

SCEPTIC: I find this argument very weak. What is this - give us $50 billion to take a man to Mars, and we'll throw in a free school or two along the way? I think if you want to improve education, you should spend the money directly. A headmaster of any underfunded school will probably say exactly the same thing.

SPOKESMAN: Yes, but as I've argued previously, it's perfectly reasonable to be able to fund both! And if no - one wants to be educated, funding education is harder to justify. The government of any country is still supposed to be the servant of the people! I think the main point behind selling space exploration from an educational point of view is that it really reaches kids. A really genuine space programme is something cool that kids really get into. It isn't an exaggeration to say that it inspires them. Some then go into science for a career to get closer to space exploration. A select few achieve this goal. Many - in fact most - don't and up in science at all, but go on to some other career. But the important point is that they have been inspired to apply themselves to something. If you're ever in doubt of the power of space exploration to move children, I suggest you take some out on a clear night to look at the stars.

SCEPTIC: But this isn't enough to justify the endeavour. My four year old daughter gets more inspired by Sesame Street than she does by space documentaries.

SPOKESMAN: Of course, not all kids are going to get carried away by space exploration! But kids are very hard to lie to. I think your headmaster would much rather have her teachers explain science through the wonder of the Universe and an exploration programme that is actually out there than through some oversimplified, abstract construction to illustrate base principles.

SCEPTIC: Base principles are also needed in education. You can't just give kids the Universe and say "go ahead and figure it out." A similar approach has been tried in the States in the seventies, and briefly in Britain, and it failed disastrously in both places.

SPOKESMAN: And throughout the last century, children were taught only base principles in a very abstract way. Kids were treated as empty vessels to be filled up with facts by their teachers. This method of teaching totally ignores educational theory dating back two thousand years to the time of the Greeks. I think it has been established that, while children were learning the required material, the "Empty Vessel" educational system was failing the children in terms of the usefulness of the education, but more importantly in that most children were utterly uninspired. Children are very different from each other, and it is always possible to find a counterexample to any rule about them. But many children need a point to their learning, a goal to chase. Space exploration provides them with such a goal.

SCEPTIC: Are you really suggesting that kids should all have space exploration as a goal?

SPOKESMAN: No! And I'm not saying that we should explore space just to provide a fraction of children with inspiration. What I am saying is that the inspiration the space programme provides this fraction of children is an invaluable side - effect of the exploration of space. Inspiration isn't the kind of thing you can throw money at and expect to grow on its own! It gets planted in the child when he or she sees something that's already out there and thinks: "wow!" Space exploration is the kind of thing that provokes this reaction in kids. And this is invaluable. Space exploration isn't going to lead directly to more schools, or provide financial benefit to them. But it will benefit all schools, in the kind of way that just isn't addressed by money. Have you ever tried to buy inspiration for your daughter?

Proposed Con 2: Space exploration is very hard

SCEPTIC: I think the whole endeavour of space exploration is beyond our capability. Let's face it, space exploration is very hard, as you yourself admitted previously! I realize the space scientists and technicians are doing their best to overcome the difficulties associated with space travel, with some spectacular success. But if my car had a twenty- percent chance of blowing up per trip, like a space rocket or the space shuttle does, I?d cycle to work every day! I think this is evidence that the whole endeavour of space travel is too hard for us right now. Let's concentrate on problems we can solve. Blake was wrong - the stars are out of reach. To paraphrase Blake, we are not ready to hold infinity in the palms of our hands.

SPOKESMAN: Yes, you're absolutely right in that space travel is hard. And the cumulative failure rate of 20 per cent for all launches since the beginning of the Space Age is fairly high when applied to everyday devices such as a car. But don't forget - space travel is still very experimental. And in comparison with other exploration endeavours, space flight has an exemplary record of safety.
Look at the exploration of the Earth. How many failed attempts were made to launch boats? How many people died in their exploration attempts or routine transits over the ages of the boat? By comparison, in the space programme, the cumulative failure rate is 20 percent. That means that in the history of space flight, including the development stages, four out of every five launches were successful. The total number of people killed in all stages of development of space flight - and here I am counting the German V2 attacks on London - is less than the number killed when the Titanic sank in 1912. Without the V2 attacks, the number of people killed in the name of space exploration falls to less than thirty. A single bus crash can kill more people that have ever died through association with the space programme. And the technical difficulties associated with the exploration of space are much greater than those associated with the exploration of the surface of the planet Earth.

SCEPTIC: Which means it can't be compared to the exploration of the Earth - the difficulties are an order of magnitude greater.

SPOKESMAN: It means that any comparison made serves to show how far we are capable of going in meeting such difficulties. Anyone who actually gets to go on a manned Mars mission, for example, will have conditions on their journey considerably nicer than those facing the men who almost starved to death or dropped dead from scurvy - and those who did! - on Columbus? journey to the New World. But if anything goes wrong, the Mars astronaut will be just as far from help as Columbus? men were. The difficulties are different in detail, but essentially the same. Don't forget, the problems space travel presents would have been utterly insoluble four hundred years ago, but the range of problems we can solve has scaled up with our technology. Though the problems are an order of magnitude greater, a comparison is possible, because our technological ability to meet such problems has increased by an order of magnitude.

SCEPTIC: But you haven't really answered my question - why do something as hard as space exploration, when the money can be spent on other, safer, easier endeavours?

SPOKESMAN: I've shown you how it isn't as hard an endeavour as you made out in your question. As we covered earlier, cutting the space program wouldn't help anything anyway. The money wouldn't be spent on other safer endeavours - most of it would end up being spent on the military. So there are no financial objections at this point.
Exploration tends to go hand in hand with what is today regarded as success in terms of civilization. Looking over history, those nations which are today respected in their time - like 14th century China or ancient Rome - are those with an active exploration programme. It seems to be indicative of the state of health of the nations.

Proposed Pro 3: Population

SPOKESMAN: At the end of the 20th century, the human species is faced with many problems, such as lack of food, unequal distribution of resources and the prospect of wars over limited water. These are all symptoms of one larger problem - the problem of overpopulation.

ADVANTAGES OF SPACE EXPLORATION:

For those that see space exploration as a waste of resources better spent to solve social ills, it is important to understand the benefits of space exploration and how the future of humankind lies with such an endeavour.

Space exploration has resulted in development of application satellites that play a vital role in modern society. These satellites provide global communication networks. They provide accurate weather/crop forecasting that every year saves countless lives and allows for farmers throughout the world to better provide food for their peoples. These satellites are critical for better understanding global environmental change issues, such as ozone depletion and climate changes, that can threaten the very biosphere in which we live.

Space exploration, born out of the cauldron of the cold war, has brought with it a lasting gift. This gift is exemplified by the first pictures of Earth from outer space taken by Apollo 8 as it circumvented the Moon on Christmas day 1968. The famous Earth Rise photograph allowed us to see the Earth as a fragile tiny life-giving biosphere amidst the vast hostile environment of the cosmos.

As we explore and study planets, we learn more about this one. Comparative planetology, the study of Earth in comparison other planets, has been instrumental in identifying global environmental problems. NASA scientists trying to understand why the surface temperature of Venus is warm enough to melt lead have proven the validity of greenhouse warming and its potential devastating effects. Likewise, planetary scientists trying to understand why on Mars materials instantly oxidize due to ultraviolet light penetration from the sun identified what was causing ozone depletion back here on Earth.

The exploration of Mars will reinvigorate the US space program and will bring with it multiple benefits. Exploring Mars will bring a storehouse full of information to the possible origins of life in the cosmos, to the light it casts on the environment of Earth, to the international co-operation that it will give rise to between nations, to the scientific understandings of how humans are able to function and adapt in micro gravity environments, and to potentially extending human civilization to Mars by building closed ecological biospheres or in terraforming that plant.

Human space exploration promotes the very best that humans have to offer. A national commitment of 1% of the national budget (NASA appropriations amount to $13.5 billion out of a $1.5 trillion dollar national budget) or even 2% is definitely not only worth the costs to others, but it is worth the costs for us a nation, for the family of nations throughout the world, and for humans as a global species. Paraphrasing the scientist/astronomer known to millions, Carl Sagan, space exploration satisfies our inclination for great enterprises, wanderings, and quests that have been with us from time immemorial.

[Taken from: Fahd Shariff's Essays Page, Dated Sep, 1999]

Also Published in:

Title: Pro/con / [editors, Sally McFall et al.].
Published: Danbury, Conn. : Grolier Educational, 2002-<2003->
Chapter: Science and the Future
Topic 15: Should Governments Continue to Fund Space Exploration?
Pages 187-198
May 2002