By Greg Trotti

A Russian company may beat NASA with a next-generation Crew Exploration Vehicle (CEV). Russian aerospace company RSC-Energia plans to have a vehicle, Clipper, that could be towed into space by another vehicle, Parom. Different pieces for a mission of craft or cargo can be brought up on other Paroms or on Soyuz rockets. Assembly would occur in orbit, followed by a launch to either the Moon or Mars.

One possible purpose of a Moon mission is said to be the raw materials there that could be harvested. It is widely believed that the moon is rich in Helium-3. Helium-3 is very rare on earth, but is believed by many to be a possible source of energy for future space travel. It is believed that the moon contains hundreds of thousands tons, and the price per ton could reach somewhere in the upper millions or perhaps billions. Helium-3 is touted to contain large amounts of energy that is non-polluting and has little or no radioactive by-product. Nonetheless, the fusion of Helium-3 has yet to be perfected. Its full environmental impact, both to the moon and as a component in nuclear fusion, is yet to be fully assessed.

It would take an investment to physically mine the moon to retrieve the Helium-3. It would take further investment to return it either to the International Space Station or back to Earth. The amount of energy needed to bring it back to Earth would outweigh the benefits of the energy itself. The most likely solution is therefore to store it in space. Spacecraft could refuel after leaving the Earth’s orbit prior to going on a further space mission.

Picture courtesy of NASA.

By the Rockets Away Staff

New Horizons, the curiously-shaped craft that finally headed out to Pluto on January 19, 2006, did not have perfect launch windows for a few days before it blasted off. The first day of the expected launch saw high winds; the second day brought a power failure at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, which was the venue for mission management. But finally New Horizons was launched successfully, making it one of the most exciting voyages ever undertaken by an unmanned spacecraft.

Why so exciting? Because mankind, for the first time in history, will attempt to penetrate the secrets of Pluto, a celestial object whose status as a true planet is still a matter of debate. Like a sister object called Charon, Pluto has seen its planetary designation challenged because of its placement in the so-called Kuiper belt, an area beyond Neptune that has hordes of icy objects which share its frigid architecture. Pluto is named for the god of the underworld, the god of supreme darkness. And wouldn’t you be a little bit enshrouded in darknesss if you were 3.3 billion miles from our little Earth paradise, which is only ninety-three million miles or so from the sun?

New Horizons was launched atop an Atlas V rocket. This is the most powerful launch vehicle in the NASA arsenal. Due to the combination of three liquid propellant rocket engines and five strap-on solid propellant booster rockets, it attained the fastest launch speed on record, faster than any vehicle ever developed by men, speeding away from Earth at 36,000 miles per hour. The craft was expected to reach the moon in approximately nine hours and will continue on to Jupiter in a record 13 months.

New Horizons will use Jupiter as a flyby, producing a gravitational slingshot effect to increase velocity to 47,000 mph on its way to Pluto. As Jupiter’s gravity increases its pull on the satellite, the craft's velocity also increases. This slingshot effect will decrease New Horizons’ travel time to Pluto by approximately four years. Even though it is the fastest vehicle ever launched, New Horizons won’t actually begin its five-month study until July of 2015.

New Horizons uses a liquid-engine system fueled by hydrazine for attitude and course adjustments. On board are 24 pounds of plutonium dioxide for electrical power generation to operate the scientific instruments. A single radioisotope thermoelectric generator (RTG) will be capable of generating 240 watts of electricity delivered at 30 volts. Due to radioactive decay of the plutonium, however, power output will decrease by approximately 3.5 watts per year. As New Horizons reaches Pluto, peak power output will be about 200 watts. The instrumentation will only need approximately 28 watts for full functionality. The craft couldn’t launch without the White House go ahead, because of its highly toxic little payload.

Is this the first time we’ve sent plutonium into space? At first glance, 24 pounds seems like a lot, but actually this has been going on with eve larger quantities since 1961. The Cassini-Huygens space probe had over 72 pounds of plutonium when it launched. Russia and the US have been using RTGs - radioisotope thermoelectric generators - as a power source for unmanned spacecraft and satellites when solar cells will not work. Plutonium also makes for a very light power source.

This is not the same plutonium that is created at nuclear power plants. It’s actually plutonium 238, which uses radioactive decay to create energy, not fission. The selection of Plutonium 238 as an isotope for the RTG is based on two main charceteristics and one secondary one. The main characteristics are the half-life of the isotope and the energy produced during its radioactive decay. The isotope has to produce enough energy to power the spacecraft or satellite for enough time. You also don’t want to produce too much energy, because this can cause other problems. The secondary characteristic is the need for less radiation shielding. Plutonium 238 needs at least seven times less shielding than the other viable isotopes.

NASA has said that the likelihood of someone being hurt from the most severe accidents during launch is between 1 in 100,000 to 1 in 1 million. This would most likely happen on a launch if the storage container was damaged, causing an extra 10 to 30 people to die from cancer over a 50-year period. Plutonium is most toxic through inhalation, so someone who inhaled a tiny particle would be likely to contract lung cancer.

Most groups are concerned about the plutonium being sent back to earth, getting into the environment, including the oceans, and killing lots of people and animals. They do not believe the risk is worth it. They point out that other fuel is ready available - it would just take a longer time to get where we're going.

According to the Global Network Against Weapons and Nuclear Power in Space, there have been many such nuclear accidents in the past involving official spacecraft that were carrying plutonium. On November, 1996, a Russian Mars ’96 space vehicle blew up over Chile and Bolivia, losing its payload of a half pound of plutonium. When the Apollo 13 landed near New Zealand, it deposited 8.3 pounds of plutonium that is allegedly still on the ocean floor. And back in April of 1964, U.S. Transit 5BN-3 lost 2.1 pounds of Plutonium-238, which vaporized in the atmosphere and spread worldwide. Dr. John Gofman, Professor Emeritus of Molecular and Cell Biology in the University of California at Berkeley and co- discoverer of various radioactive isotopes, believes this was a major contributor to the increase in cancers around the world today.

Karl Grossman, professor of journalism at the State University of New York/College at Old Westbury and author of The Wrong Stuff: The Space Program's Nuclear Threat To Our Planet (Common Courage Press), says: "By presenting the dangers of the plutonium that could have been released in a New Horizons accident in the context of background radiation, NASA was mixing radioactive apples and oranges. Plutonium is an alpha-emitter, not a gamma- emitter, and a piece of paper or skin can block the radioactivity it sends off. The key issue is that only the tiniest amount of plutonium, a millionth of a gram, getting lodged in a person's lung can cause cancer. That's why plutonium has long been described as the most toxic radioactive substance - so little can kill. It's not water-soluble, so an inhaled particle remains lodged in the lung.”

According to Professor Grossman, “If the 24 pounds of plutonium on New Horizons were released in an accident as vapor or dust and drifted the distance around the launch site that NASA in its Environmental Impact Statement said it could drift - up to 62 miles - and, further, if some of it moved in the troposphere around the world, which NASA said would also happen, a significant number of people would have breathed in particles of plutonium and been left with lung cancer. Considering that NASA in the EIS said the odds of an accident releasing plutonium for the New Horizons mission were 'estimated to be approximately 1 in 300,' that prospect was far from unlikely." (Karl Grossman also wrote and narrated the TV documentary, Nukes In Space: The Nuclearization and Weaponization of the Heavens [EnviroVideo] ).

Obviously, not all scientists agree with the Global Network Against Weapons and Nuclear Power in Space. According to Dr. Gregory Matloff, Assistant Professor of Astronomy and Physics at New York City College of Technology, CUNY, “Any spacecraft further out than Mars requires some form of nuclear battery, since sunlight is too diffuse in the outer solar system. Environmental effects from the worst possible launch accident that could occur for a probe using such batteries have been exhaustively modeled. I believe that the safety measures employed by NASA are adequate. In the indefinite future, a number of techniques (such as the electrodynamic tether) will become available as alternatives to the nukes that tap cosmic energy sources."

After receiving this opinion from Mr. Grossman, after conveying our intentions to Mr. Grossman, Rockets Away! contacted the Johns Hopkins University Applied Physics Laboratory Office of Communications and Public Affairs for an official response to Mr. Grossman's assertions. They promised us they would provide this to one of the appropriate persons knowledgeable about the New Horizons mission in this specific area. Just prior to the release of this issue, we received the following statement from Alice Caponiti, Nuclear Material and Safety Manager, U.S. Department of Energy.

Ms. Caponiti says: "An estimated dose that a person could receive from exposure to radioactive material takes into account the type of radiation and the nature of exposure and uptake in the body. Comparisons of potential doses from an accidental release of plutonium to doses received from background radiation are valid and are not 'apples and oranges', as Mr. Grossman asserts."

"Mr. Grossman significantly overstates the amount of nuclear material that could have been released from the power source in the event of an accident. Multiple layers of safety features protect the nuclear material under accident conditions. Even if a release had occurred, the nuclear material is in a ceramic form (like a dinner plate) and would have shattered mostly into large pieces that would likely have remained near the impact site."

"For the New Horizons mission, there was a one in 300 probability of any accident during the entire mission that could have released nuclear material. The most likely accidents would have involved small releases that would lead to either no exposure or very low radiation doses to individuals. At exposures this small, no health effects would be expected. The nuclear safety analyses also examined more severe, but less likely types of accidents. Even in the event of a more severe accident, contamination was still expected to remain near the impact site and present a low risk to the public."

This article was written by Johnny Blue Star, with contributions by Greg Trotti, Richard Kirkpatrick and Dave Gieber, Technical Adviser. Picture courtesy of NASA.

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