How Solar Energy Beats Nuclear Power on Earth and in Space
A demonstration that in space, as on Earth, solar is an alternative to dangerous nuclear power is to come this week when a solar-powered spacecraft called Rosetta will rendezvous with a comet at 375 million miles from the Sun.
Artist’s impression of the Philae lander. Credits: ESA–J. Huart, 2013
The Rosetta space probe, energized with solar power, is to meet up Wednesday with Comet 67P/Churyumov-Gerasimenko. It will begin making observations, relaying back to Earth high-resolution images and information from its sensors of the two-and-a-half mile wide comet. Rosetta will subsequently send a lander down to the comet that will drill into it and perform a variety of experiments. For a year, Rosetta will fly alongside the comet, named after the two Ukranian astronomers who discovered it in 1969.
For decades, the U.S. and the Soviet Union, and now Russia, stressed the use of atomic energy as a source of power in space—and there have been accidents as a result.
The most serious were the falls back to Earth of a U.S. satellite with a SNAP-9A plutonium-238 radioisotope thermal generator on board in 1964, disintegrating as it fell, dispersing plutonium worldwide, and of the Soviet Cosmos Satellite 954 in 1978, with an atomic reactor on board, also breaking up, and spreading nuclear debris for hundreds of miles across the Northwest Territories of Canada.
The late Dr. John Gofman, professor of medical physics at the University of California at Berkeley, long connected the SNAP-9A accident and its dispersal of plutonium with a global increase in lung cancer. Canada demanded compensation for the Cosmos-954 accident which the Soviet Union eventually paid, in part.
Now all satellites are solar-powered as is the International Space Station. But there has been a push to continue to use nuclear power on space probes with NASA and formerly Soviet and now Russian space authorities insisting that solar power cannot be harvested far from the Sun.
However, the European Space Agency (ESA) declares on its website:
The solar cells in Rosetta’s solar panels are based on a completely new technology, so-called Low-intensity Low Temperature Cells. Thanks to them, Rosetta is the first space mission to journey beyond the main asteroid belt relying solely on solar cells for power generation. Previous deep-space missions used nuclear RTGs, radioisotope thermal generators. The new solar cells allow Rosetta to operate over 800 million kilometres from the Sun, where levels of sunlight are only 4% those on Earth. The technology will be available for future deep-space, such as ESA’s upcoming Jupiter Icy Moons Explorer.
ESA notes: “ESA has not developed RTG i.e. nuclear technology, so the agency decided to develop solar cells that could fill the same function.”
Rosetta, launched in 2004, “relies entirely on the energy provided by its innovative solar panels for all onboard instruments and subsystems,” says ESA.
NASA has begun to follow ESA’s lead. It went with solar power for its Juno mission to Jupiter that is now underway. Launched in 2011, energized by solar power, the Juno space probe is to arrive at Jupiter in 2016.
At the distance at which Rosetta will encounter Comet 67P/Churyumov-Gerasimenko or at which Juno will be doing experiments involving Jupiter or ESA’s Jupiter Icy Moons Explorer will work, energy from the Sun is but a small fraction of what it is on Earth. Still, it can be effectively utilized. (NASA’s last space probe mission to Jupiter, Galileo, launched in 1989, was plutonium-powered and NASA officials insisted, including in sworn testimony countering a challenge to Galileo in federal court, that this was the only energy choice. There were numerous protests against Galileo and have been to subsequent nuclear space shots led by the Global Network Against Weapons & Nuclear Power in Space.)
Rosetta is named after the Rosetta Stone, a slab of basalt found in Egypt in 1799 with inscriptions carved on it that enabled the deciphering of hieroglyphics, the ancient language of Egypt. “As a result of this breakthrough, scholars were able to piece together the history of a lost culture,” notes ESA.
Likewise, “Rosetta’s prime objective is to help understand the origin and evolution of the Solar System,” says ESA. “The comet’s composition reflects the composition of the pre-solar nebula out of which the Sun and the planets of the Solar System formed, more than 4.6 billion years ago. Therefore, an in-depth analysis of Comet 67P/Churyumov-Gerasimenko by Rosetta and its lander will provide essential information to understand how the Solar System formed.”
ESA adds, “There is convincing evidence that comets played a key role in the evolution of the planets, because cometary impacts are known to have been much more common in the early Solar System than today. Comets, for example, probably brought much of the water in today’s ocean. They could even have provided the complex organic molecules that may have played a crucial role in the evolution of life on Earth.”
Rosetta “will be undertaking several ‘firsts’ in space exploration,” says ESA. “It will be the first mission to orbit and land on a comet.” And, Rosetta will be “the first spacecraft to witness, at close proximity” the changes in a comet as it approaches the Sun. Rosetta’s lander “will obtain the first images from a comet’s surface and make the first in-situ subsurface analysis of its composition.”
The Rosetta lander, given the name Philea, is to touch down on the comet’s surface in November and “remain operational through the end of 2015 . . . A drilling system will obtain samples down to 23 cm below the surface and will feed these to the spectrometers for analysis, such as to determine the chemical composition. Other instruments will measure properties such as near-surface strength, density, texture, porosity, ice phases and thermal properties . . . In addition, instruments on the lander will study how the comet changes during the day-night cycle, and while it approaches the Sun.”
The lander is being called Philea for Philea Island in the Nile where an obelisk was found that supplemented the use of the Rosetta Stone in the deciphering of hieroglyphics.
The cost of the mission is 1.3 billion Euros ($1.75 billion at current exchange rates) and ESA asks the question: “Why spend such a huge amount of public money on studying remote stones in space?”
ESA responds: “ESA’s task is to explore the unknown. In the case of Rosetta, scientists will be learning about comets, objects that have fascinated mankind for millennia” and “are thought to be the most primitive objects in the Solar System, the building blocks from which the planets were made. So Rosetta will provide exciting new insights into how the planets, including Earth, were born and how life began.”
There can be things that can still go wrong on the mission. Gases from the comet could affect Rosetta flying with it. Philea could fail to get hooked to the comet, although a “harpoon” system has been devised for it to anchor itself to the comet’s surface.
But if the Rosetta mission is a success it will be a superb example of a space mission that represents no nuclear threat to life on Earth and of a quest with the highest of purposes—exploring the mysteries of the Solar System and the origins of life.
Karl Grossman, professor of journalism at the State University of New York/College at Old Westbury, is the author of The Wrong Stuff: The Space Program’s Nuclear Threat to Our Planet and narrator and writer of the television documentary Nukes in Space: The Nuclearization and Weaponization of the Heavens (www.envirovideo.com).
You Might Also Like
- Moved by Flint Water Crisis, 11-Year-Old Scientist Invents Lead ... ›
- Malala Yousafzai and Greta Thunberg Finally Meet in Oxford ... ›
- Irish Teenager Wins Google Science Award for Removing ... ›
EcoWatch Daily Newsletter
By Brian Bienkowski
Fish exposed to endocrine-disrupting compounds pass on health problems to future generations, including deformities, reduced survival, and reproductive problems, according to a new study.
Low Levels Lead to Generational Impacts<p>Researchers exposed inland silverside fish to bifenthrin, levonorgestrel, ethinylestradiol, and trenbolone to levels currently found in waterways.</p><p>"Our concentrations were actually on the low end" of what is found in the wild, DeCourten said, adding that it was low amounts of chemicals in parts per trillion.</p><p>Bifenthrin is a pesticide; levonorgestrel and ethinylestradiol are synthetic hormones used in birth controls; and trenbolone is a synthetic steroid often given to cattle to bulk them up.</p><p>Such endocrine-disruptors have already been linked to a variety of health problems in directly exposed fish including altered growth, reduced survival, lowered egg production, skewed sex ratios, and negative impacts to immune systems. But what remains less clear is how the exposure may impact future generations.</p><p>For their study, DeCourten and colleagues started the exposure when the fish were embryos and continued it for 21 days.</p><p>They then tracked effects on the exposed fish, and the next two generations.</p>
Inherited Problems<p>DeCourten said the altered DNA methylation is one of the plausible ways that future generations would experience health impacts from previous generations' exposure. Hormone-disrupting compounds have been shown to impact DNA methylation, which is an important marker of how an organism will develop.</p><p>"Methyl groups are added to specific sites on the genome, [the exposure] is not changing the genome itself, but rather how the genome is expressed," she said. "And that can be inherited throughout generations."</p><p>In addition, Brander said there are essentially different "tags" that exist on DNA molecules, which tell genes how to turn on and off. She said the exposure to different compounds may be "influencing which methyl tags get taken on or off as you proceed through generations."</p><p>The researchers said the study should prompt future toxics testing to consider impacts on future generations.</p><p>"The results … throw a wrench in the current approach to regulating chemicals, where it's often short-term testing looking at simple things like growth, survival, and maybe gene expression," Brander said.</p><p>"These findings are telling us we really at least need to consider" the next two generations, she added.</p>
- Alarming Levels of Cancer-Causing Chemicals Found in Columbia ... ›
- Microplastics Are Killing Baby Fish, New Study Finds - EcoWatch ›
Poor eating habits, lack of exercise, genetics, and a bunch of other things are known to be behind excessive weight gain. But, did you know that how much sleep you get each night can also determine how much weight you gain or lose?
New Zealand’s Jacinda Ardern Wins Historic Victory Following Science-Based Leadership on COVID and Climate
- New Zealand's Ardern Pledges 100% Renewable Energy by 2030 if ... ›
- New Zealand Plans to Require Climate Risk Reporting - EcoWatch ›
- New Zealand Will Consider Climate Crisis in All Major Policy ... ›
By Laura Beil
Consumers have long turned to vitamins and herbs to try to protect themselves from disease. This pandemic is no different — especially with headlines that scream "This supplement could save you from coronavirus."
Vitamin D<p><strong>What it is: </strong>Called "the sunshine vitamin" because the body makes it naturally in the presence of ultraviolet light, <a href="https://www.sciencenews.org/article/vitamin-d-supplements-lose-luster" target="_blank">Vitamin D is one of the most heavily studied</a> supplements (<em>SN: 1/27/19</em>). <a href="https://health.gov/our-work/food-nutrition/2015-2020-dietary-guidelines/guidelines/appendix-12/" target="_blank">Certain foods</a>, including fish and fortified milk products, are also high in the vitamin.</p><p><strong>Why it might help: </strong>Vitamin D is a hormone building block that helps strengthen the immune system.</p><p><strong>How it works for other infections:</strong> In 2017, the <em>British Medical Journal</em> published a meta-analysis that suggested a daily vitamin D supplement <a href="https://www.bmj.com/content/356/bmj.i6583" target="_blank">might help prevent respiratory infections</a>, particularly in people who are deficient in the vitamin.</p><p>But one key word here is <em>deficient. </em>That risk is highest during dark winters at high latitudes and among people with more color in their skin (melanin, a pigment that's higher in darker skin, inhibits the production of vitamin D).</p><p>"If you have enough vitamin D in your body, the evidence doesn't stack up to say that giving you more will make a real difference," says Susan Lanham-New, head of the Nutritional Sciences Department at the University of Surrey in England.</p><p>And taking too much can create new health problems, stressing certain internal organs and leading to a dangerously high calcium buildup in the blood. The recommended daily allowance for adults is 600 to 800 International Units per day, and the upper limit is considered to be 4,000 IUs per day.</p><p><strong>What we know about Vitamin D and COVID-19:</strong> Few studies have looked directly at whether vitamin D makes a difference in COVID.</p>
Zinc<p><strong>What it is: </strong>Zinc, a mineral found in cells all over the body, is found naturally in certain meats, beans and oysters.</p><p><strong>Why it might help: </strong>It plays several supportive roles in the immune system, which is why zinc lozenges are always hot sellers in cold and flu season. Zinc also helps with cell division and growth.</p><p><strong>How it works for other infections: </strong><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6457799/" target="_blank" rel="noopener noreferrer">Studies of using zinc for colds</a> — which are frequently caused by coronaviruses — suggest that using a supplement right after symptoms start might make them go away quicker. That said, a clinical trial from researchers in Finland and the United Kingdom, published in January in <em>BMJ Open</em> <a href="https://bmjopen.bmj.com/content/10/1/e031662" target="_blank" rel="noopener noreferrer">did not find any value for zinc lozenges</a> for the treatment of colds. Some researchers have theorized that inconsistencies in data for colds may be explained by varying amounts of zinc released in different lozenges.</p><p><strong>What we know about zinc and COVID-19:</strong> The mineral is promising enough that it was added to some early studies of hydroxychloroquine, a drug tested early in the pandemic. (Studies have since shown that <a href="https://www.sciencenews.org/article/covid-19-coronavirus-hydroxychloroquine-no-evidence-treatment" target="_blank">hydroxychloroquine can't prevent or treat COVID-19</a> (<em>SN: 8/2/20</em>).)</p>
Vitamin C<p><strong>What it is: </strong>Also called L-ascorbic acid, vitamin C has a long list of roles in the body. It's found naturally in fruits and vegetables, especially citrus, peppers and tomatoes.</p><p><strong>Why it might help:</strong> It's a potent antioxidant that's important for a healthy immune system and preventing inflammation.</p><p><strong>How it works for other infections: </strong>Thomas cautions that the data on vitamin C are often contradictory. One review from Chinese researchers, published in February in the <em>Journal of Medical Virolog</em>y, looked at <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/jmv.25707" target="_blank">what is already known about vitamin C</a> and other supplements that might have a role in COVID-19 treatment. Among other encouraging signs, human studies find a lower incidence of pneumonia among people taking vitamin C, "suggesting that vitamin C might prevent the susceptibility to lower respiratory tract infections under certain conditions."</p><p>But for preventing colds, a 2013 Cochrane review of 29 studies <a href="https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD000980.pub4/full" target="_blank" rel="noopener noreferrer">didn't support the idea</a> that vitamin C supplements could help in the general population. However, the authors wrote, given that vitamin C is cheap and safe, "it may be worthwhile for common cold patients to test on an individual basis whether therapeutic vitamin C is beneficial."</p><p><strong>What we know about Vitamin C and COVID-19: </strong>About a dozen studies are under way or planned to examine whether vitamin C added to coronavirus treatment helps with symptoms or survival, including Thomas' study at the Cleveland Clinic.</p><p>In a review published online in July in <em>Nutrition</em>, researchers from KU Leuven in Belgium concluded that the <a href="https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD000980.pub4/full" target="_blank" rel="noopener noreferrer">vitamin may help prevent infection</a> and tamp down the dangerous inflammatory reaction that can cause severe symptoms, based on what is known about how the nutrient works in the body.</p><p>Melissa Badowski, a pharmacist who specializes in viral infections at the University of Illinois at Chicago College of Pharmacy and colleague Sarah Michienzi published an extensive look at all supplements that might be useful in the coronavirus epidemic. There's <a href="https://www.drugsincontext.com/can-vitamins-and-or-supplements-provide-hope-against-coronavirus/" target="_blank" rel="noopener noreferrer">still not enough evidence to know whether they are helpful</a>, the pair concluded in July in <em>Drugs in Context</em>. "It's not really clear if it's going to benefit patients," Badowski says.</p><p>And while supplements are generally safe, she adds that nothing is risk free. The best way to avoid infection, she says, is still to follow the advice of epidemiologists and public health experts: "Wash your hands, wear a mask, stay six feet apart."</p>
- 7 Best Vitamins and Supplements to Combat Stress - EcoWatch ›
- The 10 Best Zinc Supplements of 2020 - EcoWatch ›