The US has used Radioisotope Thermal Generator, RTG to power some spacecraft and landers, including the Curiosity Mars rover, the Galileo and Cassini missions to Jupiter and Saturn, and the New Horizons Pluto flyby. Advocates of RTG’s usage believe that RTG’s do not pose much safety risk because they are specifically designed so that they will not release the plutonium they contain in almost any possible launch accident, and as long as they hold together, they are just thermally hot, not radioactively (Muller, 2010). RTG’s are lightweight hence making them highly liable. There are those who object the use of RTG’s arguing that there is always the possibility that one could get broken open somehow, and even that tiny risk is always a primary concern. For some people, mostly opponents of nuclear power in general, it is a big concern, and launches of RTG-powered spacecraft have generated public protests. No other country has used RTG’s for space mission apart from the US. For satellites that orbit the Earth, it is much cheaper to use solar panels and batteries than to use RTG’s for power, and it also eliminates a tiny but real risk (Muller, 2010). There are those who hold onto the idea that RTG’s are nuclear reactors; however, it is clear that they are not nuclear reactors and do not have moving parts.
How natural radioactivity varies
Some locations referred to as High Background Radiation Areas have been argued to have particularly higher levels of background radiation, which often result from the terrestrial and cosmic radiation. Research has shown that the highest background radiations levels are found in China, Brazil, and India. Further, the radioactive mineral Monazite has been demonstrated to be responsible for these higher levels of radiation (Muller, 2010). In Brazil, for instance, the radiation level in most cases tends to get up to 5 mrad/hr (about 43,830 mrad/yr), which is approximately 400 times normal background in the US. On the other hand, In China, the levels are nearly as severe with levels of about 300-400 mrad/yr; while in India, doses up to 3260 mrad/yr have been noted.
Delegate your assignment to our experts and they will do the rest.
LINEAR HYPOTHESIS for nuclear radiation effect
According to Muller (2010), the concept of the linear hypothesis can be defined as a hypothesis that chances of one getting cancer tend to scale linearly with radiation doses. The hypothesis presumes that there is no precise threshold such that a particular radiation amount could increase an individual’s likelihood of developing cancer. For small radiation dosages, it could not be feasible to segregate the consequence entirely. Additionally, most of the poison does show a threshold impact, and at the lesser dosage, it could become curative. Whether the case for radiation at lesser dosage is uncertain, the overall period for the effect to occur and possible immediate complication might make it challenging to wholly separate the cause and effects, predominantly when focusing on public health. Lower risks for a person might be tolerable to that particular person, but the risk might have the serious concern in public health. For instance, the linear hypothesis indicates the danger of developing cancer from a tooth x-ray is approximately 1 in 250 million.
Difference between fission and fusion
Fission is simply the splitting of a nucleus. Studies have it that spontaneous fission often happen all of a sudden and randomly when the nucleus decays and split apart, but this mainly happens to the artificially produced isotopes and not in nature. An induced fission occurs when a nucleus is hit by a neutron which is then absorbed and in the process cause nucleus to become stable preventing it from bursting (Muller, 2010). It often occurs in nature but might also occur in the nuclear weapons and reactors. Further, fission often happens to specific isotopes of elements like uranium and plutonium. U235 is commonly adopted for nuclear fission reaction. Fusion, on the other hand, is the coming together of various elements. Some particles tend to be developed during fusion. For instance, the sun’s energy originates from a fusion of four different hydrogen nuclei and produces helium. Additionally, this creates gamma rays, positrons, and even neutrinos which comprise the sun’s energy. Some of the elements typical for fusion are hydrogen and helium (Muller, 2010).
Scientific misconceptions
Currently, people continue to hold onto scientific misconception that causes them to reach incorrect information on vital public issues. The preconceived notions are simply common conceptions founded on daily experiences. For instance, most people believe that water that flows underground must flow in streams because the water they see at the surface of the earth flows in streams. Such a preconceived notion tends to plague an individual’s view of gravity, heat, and energy. Nonscientific beliefs, on the other hand, comprises of views acquired from both mythical and religious teachings (King, 2010). A good example is a religious view about ye abbreviated history of the earth and its life forms. A disparity between this belief and scientific evidence has led to significant controversy in teaching science. Lastly, factual misconceptions are falsities that people learn at early ages and are retained into adulthood such as lightning does not strike twice in the same place. To correct these misconceptions, individuals should confront their own beliefs along with their related limitations and paradoxes and then try to reconstruct the knowledge critical to understanding the scientific model being presented.
References
King, C. J. H. (2010). An analysis of misconceptions in science textbooks: Earth science in England and Wales. International Journal of Science Education , 32 (5), 565-601.
Muller, R. A. (2010). Physics and technology for future presidents: an introduction to the essential physics every world leader needs to know . Princeton University Press.
