Space Elevators Affirmative



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Rockets

Contention two is Rockets

Rockets make exploration and development impossible—Reducing payload cost is critical to future projects and reducing dependence on Launch vehicles.


Jonathan Coopersmith, 2001, March 9, Texas A&M University, “The cost of reaching orbit: Ground-based launch systems,” Space Policy, Volume 27 Issue 2, ScienceDirect.

The high cost of launching payloads into orbit – roughly $20,000/kg – continues to deter large-scale exploration and exploitation of space. Ground-based launch systems may radically reduce costs to $200/kg, drastically altering the economics of spaceflight. Low costs will encourage the creation of new markets, including solar-based power satellites and disposal of nuclear waste. The US government should establish a goal of $200/kg by 2020 and provide the resources needed to develop such systems.

Article Outline

1. Introduction

2. Why chemical rockets?

3. Alternatives to chemical rockets

4. Creating demand: if you build it, will they come?

4.1. Space-based solar power

4.2. Nuclear waste disposal

5. The challenge

6. Conclusion

1. Introduction



When I fly from North America to Europe, I pay $6–12/ kg of me. When a satellite is launched into space, the customer (or taxpayer) pays roughly $20,000/kg. That figure is the major challenge facing space flight: until the cost of reaching orbit drastically decreases, the large-scale exploration and exploitation of space will not occur. These high launch costs have restricted access to space to those governments, corporations and organizations which can afford millions of dollars to launch a satellite. As a result, half a century after Sputnik, the annual total of all satellite launches is only a few hundred tons, the equivalent of two 747 freighter flights.1

Ground-based alternatives to chemical rockets exist, such as beamed energy propulsion and space elevators. While promising, they are all technically immature and will not develop without a substantial government investment. Just as it pushed the development of rocket technology in the 1940s and 1950s, the US government should set a grand challenge to radically reduce the cost of reaching orbit to $200 a kg by 2020. Meeting this goal must be accompanied by resources and institutional support to move the Technology Readiness Levels (TRLs) of these technologies from the laboratory to commercial fruition.

2. Why chemical rockets?

Since Sputnik launched the Space Age on 4 October 1957, chemical rockets have propelled every payload into orbit, a monopoly that will continue for the foreseeable future. Rockets have two major problems: cost and reliability. Reaching orbit today costs about $20,000/ kg, a daunting barrier.2 While very reliable, rockets are not fully reliable even after five decades of experience: the failure rate of rockets carrying communications satellites to geosynchronous orbit (GEO) in 1997–2006 was 8%. One consequence is insurance rates of 11–20%, two orders of magnitude greater than for a Boeing 747.3

The high cost of reaching orbit means satellites are built to maximize yield per kilogram with the tradeoff of high costs to develop, assemble, and test them. The ISS cost $115,000 a kg and NEAR $181,000 in 2009 dollars, while the scores of Iridium satellites cost only $7300 a kg 4.

If chemical rockets cost so much and are unreliable, why use them? The reality is that they work well enough and the entire infrastructure for space exploration and exploitation has developed around rockets. Nor is the technology static. Rockets and satellites have improved greatly in capability while the cost/kg has dropped. A 2010 Tauri Group study found that sending a kg to GEO dropped from $32,000 to $21,000 (in inflation-adjusted 2008 dollars) or by 34% from 1999 to 2008.5 New generations of rockets will lower costs, but not radically. The SpaceX Falcon 9 will cost some $5000 a kg to low-Earth orbit (LEO), almost twice the $2850 per kg expected in 2003 for its cancelled Falcon 5.6 Similarly, the 1997 Cassini cost $300,000 a kg in 1999 dollars compared with $480,000 for the 1975 Viking and $935,000 for the 1962 Mariner 4.7



What rockets have not done and cannot do is radically reduce the cost of reaching orbit. Lack of effort is not the problem. Billions of dollars have been spent over the past decades in exploring rocket-based alternatives such as single-stage-to-orbit (SSTO), reusable launch vehicles (RLVs), and other unsuccessful lines of development.8 As Jim Maser, President of Pratt & Whitney Rocketdyne, stated in 2009, the technological base for reaching orbit in 2020 will be “Much like it is today. And that is not much different from what we were doing 50 years ago.”9

Scenario 1 is Ozone

Reducing reliance on launch vehicles is key to stop ozone depletion


Foust ‘9, Editor of the Space Review (Jeff, June 15, “Space and (or versus) the Environment”, http://www.thespacereview.com/article/1395/1)

While the current rate of ozone loss is considered insignificant, the paper examined what would happen if there was a sharp increase in launch rates. If launch rates doubled every decade, they found, rising emissions from rockets would offset the decline in other ozone-depleting substances by around 2035, causing ozone depletion rates to rise again. The effect would be sooner and sharper if launch rates tripled every decade. The authors conclude that, in such a scenario, there would be a move to regulate rocket emissions that could, in the worst case, sharply restrict launch activity. With today’s launch systems, though, such an outcome seems unlikely: most forecasts for the next decade project relatively flat levels of launch activity—about 60–70 orbital launches a year—that is far short of a doubling or tripling. However, a wild card here is space tourism and other suborbital launch activity, which is projected to grow from effectively zero today to hundreds or even thousands of launches a year by the end of the next decade, if systems enter service as planned and demand for such flights matches existing projections. The Astropolitics paper doesn’t take such missions, or interest in point-to-point suborbital or hypersonic travel, into account. Martin Ross, lead author of the paper at the Aerospace Corporation, said in an email last week that this is an area they will be looking at. They will also be studying the effect on ozone by emissions from hybrid rocket motors like the one being developed for SS2, something that he said there currently isn’t any information about. In an op-ed in last week’s issue of Space News, Ross urged the space industry to address this issue head-on rather than avoid it in the hopes it might go away on its own. “It is clear that the risk of regulation that would cap or even tax space systems according to the amount of ozone depletion they cause is small, but it is real,” he wrote. He added: “Historically, technical activities with high visibility—such as space operations—often excite unpredictable public and regulatory attention. Combined with a lack of scientifically reliable environmental effects data, the risk of idiosyncratic and overly restrictive regulation is high.”

Ozone Depletion causes Extinction


Greenpeace, 1995 Full of Homes: The Montreal Protocol and the Continuing Destruction of the Ozone Layer, http://archive.greenpeace.org/ozone/holes/holebg.html.

When chemists Sherwood Rowland and Mario Molina first postulated a link between chlorofluorocarbons and ozone layer depletion in 1974, the news was greeted with scepticism, but taken seriously nonetheless. The vast majority of credible scientists have since confirmed this hypothesis. The ozone layer around the Earth shields us all from harmful ultraviolet radiationfrom the sun. Without the ozone layer, life on earth would not exist. Exposure to increased levels of ultraviolet radiation can cause cataracts, skin cancer, and immune system suppression in humans as well as innumerable effects on other living systems. This is why Rowland's and Molina's theory was taken so seriously, so quickly - the stakes are literally the continuation of life on earth.



Scenario 2 is Space Junk

Dependence on launches means debris cascade effect is inevitable—this will make space unusable


Lynda Williams 10, Professor of Physics @ Santa Rosa Junior College, “Irrational Dreams of Space Colonization” Peace Review, The New Arms Race in Outer Space 22.1 Spring 2010 [HT]

Available Online @



Since the space race began 50 years ago with the launch of Sputnik, the space environment around Earth has become overcrowded with satellites and space debris, so much so, that circumterrestrial space has become a dangerous place with an increasing risk of collision and destruction. Thousands of pieces of space junk created from launches orbit the Earth in the same orbit as satellites, putting them at risk of collision. Every time a rocket is launched, debris from the rocket stages are put into orbital space. In 2009 there was a disastrous collision between an Iridium satellite and a piece of space junk that destroyed the satellite. In 2007 China blew up one of its defunct satellites to demonstrate its antiballistic missile capabilities, increasing the debris field by 15%. There are no international laws prohibiting anti-satellite actions. Every year, since the mid 1980s, a treaty has been introduced into the UN for a Prevention of an Arms Race in Outer Space (PAROS), with all parties including Russia and China voting for it except for the US. How can we hope to pursue a peaceful and environmentally sound route of space exploration without international laws in place that protect space and Earth environments and guarantee that the space race to the moon and beyond does not foster a war over space resources? Indeed, if the space debris problem continues to grow unfettered or if there is war in space, space will become too trashed for launches to take place without risk of destruction.

This independently causes miscalculation and accidental nuclear war


David Ritchie, IT Business Relationship Manager at SELEX S&AS, 1982, Spacewar, http://spacedebate.org/evidence/1768/

Perhaps the greatest danger posed by the militarization of space is that of war by accident. At any given time, several thousand satellites and other pieces of equipment -- spent booster stages and the like -- are circling the earth, most of them in low orbit. The space immediately above the atmosphere has begun to resemble an expressway at rush hour. It is not uncommon for satellites to miss each other by only a kilometer or two, and satellites crashing into each other may explain some of the mysterious incidents in which space vehicles simply vanish from the skies. One civillian TV satellite has been lost in space; it never entered its intended orbit, and no signals were heard from it to indicate where it might have gone. Collision with something else in space seems a reasonable explanation of this disappearance. Even a tiny fragment of metal striking a satellite at a relative velocity of a few kilometers per second would wreck the satellite, ripping through it like a Magnum slug through a tin can. Now suppose that kind of mishap befell a military satellite -- in the worst possible situation, during a time of international tension with all players in the spacewar game braced for attacks on their spacecraft. The culpable fragment might be invisible from the ground; even something as small and light as a paper clip could inflict massive damage on a satellite at high velocity. Unaware of the accident, a less than cautious leader might interpret it as a preconceived attack. Wars have begun over smaller incidents.


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