First of all not to consider me a conspiracy theorist, but isn't landing on the moon a questionable issue? I am really not an expert in astronomy but let's assume that a moon landing has happened.
1- How would the Gamma rays and cosmic rays affect the equipments on the lunar surface and would these equipments function normally like on earth?
2-Could the enormous amounts of solar energy bursts be avoided somehow for protecting human flesh?
3-How is it possible for an FM or any kind of data transmission type be achieved in an environment that has nothing but an empty space? How would the electromagnetic waves travel and enter the earth's atmosphere to be captured by the receivers?
4-What is the bright lunar surface real temperature and is there a way to equip an astronaut to protect him from the over-heat?
Thanks for sharing any ideas that could explain these points not just for me, but for interested people who might view this question.
First of all *not to consider me a conspiracy theorist(, but isn't landing on the moon a questionable issue?
Only to conspiracy theorists. To everyone else, no, it's not a questionable issue. My father in law helped send men to the Moon. I have worked with a number of people who sent men to the Moon. I was once called on the carpet in Gene Kranz's office. I find it extremely insulting to think that it is a questionable issue. So excuse me if my response might seem be a bit insulting.
How would the Gamma rays and cosmic rays affect the equipments on the lunar surface and would these equipments function normally like on earth?
Equipment and humans did not suffer immediate damage given the short period of time that humans did spent on the Moon. One of the effects of mild radiation is increased risk of cancer (but that's a long-term effect). The men who went to the Moon (and they did go to the Moon) did indeed suffer increased cancer rates compared to the Earth-bound population.
Could the enormous amounts of solar energy bursts be avoided somehow for protecting human flesh?
By luck, there were no large solar energy bursts when men were in space on the way to the Moon, on the Moon, or coming back from the Moon. A large coronal mass ejection event did happen on August 7, 1972, but that was (by luck) sandwiched between the Apollo 16 and Apollo 17 lunar missions.
How is it possible for an FM or any kind of data transmission type be achieved in an environment that has nothing but an empty space? How would the electromagnetic waves travel and enter the earth's atmosphere to be captured by the receivers?
This question makes no sense. Look up in the sky during the day. What do you see? You see the Sun. Look up in the sky at night. What do you see? You see the Moon, the planets, stars, and if you live in an area with low humidity and limited light pollution, you even see other galaxies. With your naked eye. The only difference between light and FM is frequency. Both are forms of electromagnetic radiation. Electromagnetic radiation travels unfettered through empty space.
What is the bright lunar surface real temperature and is there a way to equip an astronaut to protect him from the over-heat?
The first defense against the temperature extremes of the space environment is very simple: It's coloration. A spacesuit that was jet black in the visible range but white in the thermal infrared would have quickly killed the NASA astronauts on the Moon due to overheating. On the flip side, a spacesuit that was white in the visible range but jet black in the thermal infrared would have resulted in overcooling. The space suits worn by the NASA astronauts on the Moon were white in the visible range but grayish in the thermal infrared. NASA spent a lot (a whole lot) of money investigating different fabrics, different dyes, and different paints. Passive thermal control is the first step in any space operation against the extremes of space. Active thermal control addresses what little passive thermal control can't address.
Astronauts' Children Unlikely To Inherit Cosmic Ray-Induced Genetic Defects
Upton, NY - Male astronauts exposed to cosmic rays in space are not likely to pass on possible mutations caused by the rays to their offspring, according to a new study by a collaboration that includes a scientist from the U.S. Department of Energy&rsquos Brookhaven National Laboratory. The results are published in the April 11, 2005, online issue of the Proceedings of the National Academy of Sciences.
&ldquoWe concluded that one hazard to male astronauts as a result of exposure to cosmic rays - high-energy, heavy nuclei that zoom in from deep space - is probably temporary sterility, but not significant effects to their future offspring,&rdquo said biophysicist Richard Setlow, the Brookhaven scientist who participated in the research.
Cosmic-ray exposure could pose serious health risks to astronauts, who are not protected by Earth&rsquos atmosphere and magnetic field - natural defense systems that prevent most cosmic rays from reaching the ground. Compared to high-energy electromagnetic radiation, such as x-rays and gamma rays, cosmic rays may cause more severe damage to cells and are more likely to result in gene mutations or cancer. Scientists are now using animals to model the health effects of cosmic-ray exposure on humans.
To test how cosmic-ray exposure might affect the children of astronauts, Setlow and his collaborators used Medaka fish, which are small fresh-water fish native to Japan, South Korea, and China. The group exposed male Medaka to one of two types of high-energy nuclei - iron and carbon - that simulate cosmic rays. The iron-nuclei exposures were performed at Brookhaven&rsquos Alternating Gradient Synchrotron facility, and the carbon exposures were carried out at the National Institute of Radiological Sciences in Chiba, Japan.
After exposure, the males were mated to non-exposed females. Fifteen to 20 embryos were collected daily for several months and observed under a microscope at the University of Tokyo. &ldquoMedaka fish were an excellent system to use for this study,&rdquo said Setlow. &ldquoTheir biggest advantage is that the covering of their embryos is clear, allowing us to visually observe mutations within a few days of fertilization.&rdquo
The researchers looked for particular signs that the male Medaka - specifically, their sperm - had been damaged by the nuclei: dead embryos, which pointed to the presence of dominant lethal mutations, and color abnormalities, which indicated that a permanent, but not lethal, genetic change had occurred.
The group found that, in total, mutations resulting from exposure to iron and carbon nuclei occurred somewhat more frequently than mutations in fish exposed to gamma rays, which served as a control group. But within the total, dominant lethal mutations occurred far more frequently than color mutations. This indicates that sperm cells in male astronauts exposed to cosmic rays are more likely to die (causing temporary sterility) than undergo a non-lethal mutation that could pass on to children.
This research was supported by the National Aeronautics and Space Administration and the Ministry of Education, Culture, Sports, Science and Technology in Japan. The experiments were approved by Brookhaven Lab&rsquos Institutional Animal Care and Use Committee and The University of Tokyo Animal Bioscience Committee.
Deep-Space Radiation Could Damage Astronauts' Guts
Deep-space missions, to Mars and beyond, could spell trouble for astronauts, according to new research showing that cosmic radiation can damage the digestive tract, stomach and colon.
Spending weeks or months in space can lead to muscle loss, deterioration in cognitive ability and bone formation, and even vision problems for astronauts. As we prepare to send astronauts deeper into space, researchers are investigating how these even-longer journeys will affect the human body.
"While short trips, like the times astronauts traveled to the moon, may not expose them to this level of damage, the real concern is lasting injury from a long trip, such as a Mars [mission] or other deep-space missions, which would be much longer," Kamal Datta, the study's lead investigator and project leader of the NASA Specialized Center of Research (NSCOR) at Georgetown University Medical Center, said in a statement. [What Does Space Travel Do to Your Gut Microbes? (Video)]
To simulate how galactic cosmic radiation in deep space will affect future astronauts, researchers at Georgetown University Medical Center studied radiation's impact on the small intestine of mice. Their findings suggest that exposure to a low dose of iron radiation could cause serious gastrointestinal (GI) damage, as well as tumor growth in the stomach and colon, according to the statement.
It&rsquos important to consider how radiation will impact astronauts on longer space missions because the digestive tract is an important source of immune function in the body. Generally, brand-new cells replace the top layer of cells in our GI tract every three to five days. However, heavy-ion radiation tends to disrupt this process, causing the GI tissue to break down and causing long-term problems, according to the study.
When new cells can't replenish properly, it affects how the human body absorbs nutrients and, as a result, causes abnormal or cancerous tissue growth.
Galactic cosmic radiation doesn't affect humans on Earth, because the planet's magnetosphere protects us. However, heavy ions such as iron and silicon that are found in deep space can damage the human body, because these atoms have a "greater mass compared to no-mass photons such as X-rays and gamma (&gamma)-rays, [which are] prevalent on Earth, as well as low-mass protons in outer space," Datta said in the statement.
For the study, researchers exposed one group of mice to heavy ions, while another group received only gamma-rays. The scientists then compared the results from these two groups with those of an unexposed control group.
The mice exposed to iron radiation exhibited cancerous tissue growth, as well as DNA damage that increased the mice's number of senescent cells, a type of cell that is incapable of regular cell division or regeneration. Specifically, these cells can slow down the replacement of healthy GI cells and, as a result, slow down normal GI function.
Senescent cells "generate oxidative stress and inflammatory molecules that induce more damage," Datta said in the statement. "This greatly affected migration of cells that are needed to replace the intestinal lining, which slowed down GI functioning."
The radiation appeared to cause permanent damage, according to the study. Also, the researchers suggested that exposure to heavy ions may cause similar damage responses in other organs.
"With the current shielding technology, it is difficult to protect astronauts from the adverse effects of heavy-ion radiation," Datta said. "Although there may be a way to use medicines to counter these effects, no such agent has been developed yet."
While the mice were used only as model of what astronauts could experience, the researchers said they plan to continue studying the effects of radiation in mice so that they can better understand the risk astronauts face during longer-duration missions.
"It is important to understand these effects in advance, so we can do everything we can to protect our future space travelers," Datta said.
The findings were published Monday (Oct. 1) in the journal Proceedings of the National Academy of Sciences.
The Milky Way’s newfound high-energy glow hints at the secrets of cosmic rays
The Tibet AS-gamma experiment (shown) detects high-energy gamma rays by observing showers of particles produced when a gamma ray hits Earth’s atmosphere.
The Institute of High Energy Physics of the Chinese Academy of Sciences/Xinhua/Alamy Stock Photo
February 2, 2021 at 12:16 pm
The Milky Way glows with a gamma ray haze, with energies vastly exceeding anything physicists can produce on Earth, according to a new paper. Gamma rays detected in the study, to be published in Physical Review Letters, came from throughout the galaxy’s disk, and reached nearly a quadrillion (10 15 ) electron volts, known as a petaelectron volt or PeV.
These diffuse gamma rays hint at the existence of powerful cosmic particle accelerators within the Milky Way. Physicists believe such accelerators are the source of mysterious, highly energetic cosmic rays, charged particles that careen through the galaxy, sometimes crash-landing on Earth. When cosmic rays — which mainly consist of protons — slam into interstellar debris, they can produce gamma rays, a form of high-energy light.
Certain galactic environments could rev up cosmic ray particles to more than a PeV, scientists suspect. In comparison, the Large Hadron Collider, the premier particle accelerator crafted by humans, accelerates protons to 6.5 trillion electron volts. But physicists haven’t definitively identified any natural cosmic accelerators capable of reaching a PeV, known as PeVatrons. One possibility is that supernova remnants, the remains of exploded stars, host shock waves that can accelerate cosmic rays to such energies (SN: 11/12/20).
If PeVatrons exist, the cosmic rays they emit would permeate the galaxy, producing a diffuse glow of gamma rays of extreme energies. That’s just what researchers with the Tibet AS-gamma experiment have found. “It’s nice to see things fitting together,” says physicist David Hanna of McGill University in Montreal, who was not involved with the study.
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After cosmic rays are spewed out from their birthplaces, scientists believe, they roam the galaxy, twisted about by its magnetic fields. “We live in a bubble of cosmic rays,” says astrophysicist Paolo Lipari of the National Institute for Nuclear Physics in Rome, who was not involved with the research. Because they are not deflected by magnetic fields, gamma rays point back to their sources, revealing the whereabouts of the itinerant cosmic rays. The new study “gives you information about how these particles fill the galaxy.”
Lower-energy gamma rays also permeate the galaxy. But it takes higher-energy gamma rays to understand the highest-energy cosmic rays. “In general, the higher the energy of the gamma rays, the higher the energy of the cosmic rays,” says astrophysicist Elena Orlando of Stanford University, who was not involved with the research. “Hence, the detection … tells us that PeV cosmic rays originate and propagate in the galactic disk.”
Scientists with the Tibet AS-gamma experiment in China observed gamma rays with energies between about 100 trillion and a quadrillion electron volts coming from the region of the sky covered by the disk of the Milky Way. A search for possible sources of the 38 highest-energy gamma rays, above 398 trillion electron volts, came up empty, supporting the idea that the gamma rays came from cosmic rays that had wandered about the galaxy. The highest-energy gamma ray carried about 957 trillion electron volts.
Tibet AS-gamma researchers declined to comment on the study.
Scientists have previously seen extremely energetic gamma rays from individual sources within the Milky Way, such as the Crab Nebula, a supernova remnant (SN: 6/24/19). Those gamma rays are probably produced in a different manner, by electrons radiating gamma rays while circulating within the cosmic accelerator.
Questions or comments on this article? E-mail us at [email protected]
A version of this article appears in the February 27, 2021 issue of Science News.
UPDATE: Galactic Cosmic Rays Continue to Rise and Human Effect
Yes, it’s me. Happy to be presenting the latest news and research as it occurs. It does appear published findings are reflective of my 2012 Equation. Cheers, Mitch
Radiation is a form of energy that is emitted in the form of rays, electromagnetic waves, and/or particles. In some cases, radiation can be seen (visible light) or felt (infrared radiation), while other forms – like x-rays and gamma rays – are not visible and can only be observed with special equipment.
Galactic Cosmic Ray collisions in the body can be harmful because they can damage the DNA in cells. Remember, a single cosmic ray has a large amount of energy. If it collides with DNA, it will destroy part of that DNA strand. DNA contains instructions for the cell to function properly. When the DNA is damaged, the cell will malfunction. Usually the cell will then die, but sometimes it can reproduce itself. If that happens on a large enough scale, the person may develop cancer.
Galactic Cosmic radiation is a well-known cause of single-event upsets (SEU) on disruption to electrical circuits in electronic devices. It most commonly occurs with devices such as laptop computers, cell phones, and personal digital assistants. Research presented by the Heart Rhythm Society, indicate some patients with Implantable Cardioverter-Defibrillators (ICDs) who experienced ionizing radiation strikes that discharged elements in the Defib during air travel, may be attributed to exposure of Galactic Cosmic Radiation while on commercial airline flights. These cases highlight the significant impact of SEUs on ICD patients clinical and the need for further recognition and study of this problem.
NASA’s Cosmic Ray Telescope for the Effects of Radiation (CRaTER), studies radiation environment and its biological impacts by measuring galactic and solar cosmic ray radiation behind a “human tissue-equivalent” plastic.
MOVIE – C LICK HERE
CRaTER investigation goals are to measure and characterize the deep space radiation environment in terms of Linear Energy Transfer (LET) spectra of galactic and solar cosmic rays (particularly above 10 MeV) in Low Earth Orbit (LEO). It will also investigate the effects of shielding by measuring LET spectra behind tissue-equivalent plastic. Test models of radiation effects and shielding by verifying/validating model predictions of LET spectra with LRO measurements.
Stay Tuned For Ongoing News and Events
What are Gamma Rays and How They Affect the Human Body and the Earth?
Just like there are sound waves we can’t hear (but other animals can), there is also an enormous range of light that our eyes can’t detect. The electromagnetic spectrum describes all the wavelengths of light, both seen and unseen, where most of them are invisible to us. The entire spectrum consists of a wide range of light from radio waves to gamma rays. Gamma rays have the smallest wavelength and the most energy of any other wave in the electromagnetic spectrum. These waves generate in nuclear explosions and reactions which form unstable atoms known as radioactive atoms.
Gamma rays travel a long distance before they reach the Earth’s atmosphere and get absorbed in it. Different wavelengths of light penetrate the Earth’s atmosphere to different depths. Gamma rays are the most energetic forms of light and produce by the hottest regions of the universe. Some violent events also create them, such as supernova explosions, the decay of radioactive materials in space, black holes, neutron stars, and pulsars, etc.
Gamma rays have frequencies higher than about 1,018 cycles per second, or hertz (Hz), and wavelengths of less than 100 picometers (A picometer is one-trillion of a meter.) Gamma rays have enough energy to cause damage to living tissue, but almost all cosmic gamma rays get blocked by Earth’s atmosphere. They are highly penetrating and interacts with matter through ionization via three processes: photoelectric effect, Compton scattering, or pair production.
Exposure to low levels of radiation does not cause immediate health effects but can cause a small increase in the risk of cancer over a lifetime. The risk increases as the dose increases: the higher the dose, the greater the risk. Conversely, the cancer risk from radiation exposure declines as the dose falls: the lower the intensity, the lower the risk. Children and fetuses are especially sensitive to radiation exposure. The cells in children and fetuses divide more rapidly, providing more opportunity for radiation to disrupt the process and cause cell damage. However, the sensitivity varies according to age and sex.
Some forms of these radiations are in the natural environment, and some are due to modern technology. Whether natural or human-made, radiation can both be harmful and beneficial to the environment. The sun, for example, can have both positive and negative effects, which is a source of ultraviolet rays. On the other hand, the ionizing radiations such as x-rays, gamma rays, alpha, and beta particles can be particularly harmful in excessive amounts. It has devastating effects on the environment, such as retard the growth of plants and seeds, disrupts the structure of DNA in living organisms, reproduction capabilities of microorganisms, can change pollination patterns, source of photochemical smog, etc.
Low doses of radiation have also proved to be beneficial in some instances. It can kill germ cells and can be used to treat mutations taking place in the body. Foods treated with low doses of radiation kill the toxic elements in it, and thus food can be preserved for a long time. Radiation that produces light is essential for the growth of plants, but the radiation level must be optimum. Too much exposure to radiation will destroy plant life.
Thus, no human activity is devoid of associated risks. The effect of gamma rays on the human body and environment can be assessed from the fact that the benefit caused by them to humankind, if appropriately regulated, are more than its harmful impacts.
The Outer Heliosphere: The Next Frontiers
3.1 The injection of low-energy pickup ions
PUI magnetic mirroring at a nearly perpendicular TS is not an option for 1 st stage acceleration because only very high energy particles will be reflected [ 18 ], and simulations show that shock drift acceleration is only effective in the presence of high amplitude turbulence [ 28 ]. However, then shock drift can be interpreted as standard diffusive shock acceleration operating above a low energy threshold [ 29 ]. Such high levels of turbulence seem unlikely for the TS [ 30 ].
The MRI mechanism, on the other hand, is ideally suited for the pre-acceleration of low energy PUIs at the TS because of the preferential reflection and acceleration of PUIs with a small velocity component along the shock normal [ 7 ]. Test particle simulations show that unaccelerated PUIs can be efficiently pre-accelerated at a perpendicular shock to energies of
1 MeV which should be sufficient for injection [ 7 ]. This and other work also suggest that hard MRI spectra with an omnidirectional distribution function fMRI (p) ∝ p − 4 result for uncooled
1 keV PUIs. The implication of these MRI spectra are an associated large MRI pressure of the order of the upstream solar wind ram pressure given that a significant fraction of PUIs are MRI-accelerated as predicted by theory [ 7 ]. This suggests that self-consistent calculations need to be done to investigate whether TS mediation by the MRI particles and the ACR source that develops from these particles after injection will not weaken the TS to such a degree that MRI acceleration and injection becomes inefficient. This will be discussed in 3.2.
It might be argued that the MRI acceleration mechanism is not the answer for local PUI pre-acceleration at the TS because it predicts the preferential pre-acceleration of the lighter PUI elements [ 7 ] while the opposite has been concluded from the observed composition of the ACR component [ 1 ]. Based on two models for perpendicular diffusion, namely, either a resonant diffusion model using a classical scattering approach, or a postulated model determined by field line random walk, a recent calculation shows that a threshold velocity for injection into standard diffusive shock acceleration can be derived which, when applied to the locally MRI pre-accelerated PUIs at the TS, results in ACRs with a similar composition as observed [ 31 ].
The possibility also exists that the TS is not nearly perpendicular but somewhat more oblique on average. In this case stochastic magnetic mirroring acceleration becomes a candidate for low-energy PUI pre-acceleration because it operates at much lower energies than for a nearly perpendicular TS. Unaccelerated PUIs, however, do not have enough energy to undergo magnetic mirroring at the TS so that pre-acceleration upstream is needed [ 18, 19 ]. However, recent simulations show that unaccelerated PUIs can be injected into the magnetic mirroring mechanism at a more oblique TS with the aid of MRI acceleration [ 19 ]. This implies that at a more oblique TS low-energy PUIs might locally be pre-accelerated in two stages followed by standard diffusive shock acceleration as the third stage.
Another argument is that the TS will only be nearly perpendicular on average, but some part of the time quasi-parallel when the threshold is lower. Diffusive shock acceleration of PUIs during times when the TS is quasi-parallel can then serve to bring PUIs across the threshold. Alternatively, PUIs might be pre-accelerated where the TS is most of the time quasi-parallel as expected at high heliolatitudes and then be transported down toward the equatorial plane along the TS front where the TS is expected to be nearly perpendicular. This would be effective when the polarity of the IMF was directed inward above, and outward below, the HCS, in which case particles would drift from high to low latitudes along the TS in both the northern and southern hemispheres.
On the basis of work referenced it seems plausible that both low-energy PUIs locally pre-accelerated at the TS as well those pre-accelerated upstream will contribute to the formation of the ACR component. The challenge for current and future research is to find which part of the PUI spectrum makes the dominant contribution.
What are the Gamma rays and Cosmic rays effects on humans and equipments? - Astronomy
This paper numerically follows the evolution of SNRs taking the nonlinear effects of particle acceleration in shock waves into account. Several SNR models with different efficiencies for the conversion of the SN explosion energy E(SN) into cosmic rays (CRs) are discussed. The gamma-ray fluxes from pi(0) decay yield 10 exp -10 ph/sq cm/s for a typical SNR with a small amount of CR energy at a time of 300 yrs and increase almost as R(s)-cubed due to geometric effects. SNRs with higher fractions of CRs or SNRs evolving into a medium of higher ambient density produce gamma-ray fluxes of up to about 10 exp -6 ph/sq cm/s. The radius of the forward shock varies between 1 pc and 70 pc for these gamma-ray fluxes. In the latter case the gamma-ray fluxes are almost constant between 10,000 and 10 exp 6 yrs. The effects of radiative cooling alter the overall energetics of an SNR, but between 10 and 30 percent of the E(SN) is converted into high-energy particles.
What do the studies show?
Atomic bomb survivors
Much of what we know about cancer risks from radiation is based on studies of the survivors of the atomic bombs in Nagasaki and Hiroshima. These people had higher risks of some, but not all cancers. Studies have found an increased risk of the following cancers (from higher to lower risk):
- Most types of leukemia (although not chronic lymphocytic leukemia)
- Multiple myeloma
- Thyroid cancer
- Bladder cancer
- Breast cancer
- Lung cancer
- Ovarian cancer
- Colon cancer (but not rectal cancer)
- Esophageal cancer
- Stomach cancer
- Liver cancer
- Skin cancer (besides melanoma)
For most of these cancers, the risk was highest for those exposed as children, and was lower as the age at exposure increased. Those exposed while still in the womb (in utero) had lower risks than those exposed during childhood.
Higher radiation exposure was linked to higher risk of cancer, but even low amounts of radiation were linked to an increased risk of getting and dying from cancer. There was no clear cut-off for safe radiation exposure.
These cancers took years to develop, but some cancers appeared sooner than others. Deaths from leukemia went up about 2 to 3 years after exposure, with the number of cases peaking after about 10 years and going down after that. Solid tumors took longer to develop. For example, excess deaths from lung cancer began to be seen about 20 years after exposure.
Children and adolescents living near the Chernobyl plant at the time of the accident had an increased risk of thyroid cancer linked to exposure to radioactive iodine. The risk was higher in areas that were iodine deficient. This increased risk was not seen in adults living in the area.
Workers employed in cleanup operations from 1986-1990 had an increased risk of leukemia (all types). These individuals had higher and more prolonged radiation exposures that the population residing around the plant.
Nuclear weapons testing
Studies suggest that some people who were children during the period of above ground nuclear testing in the US may develop thyroid cancer as a result of exposure to radioactive iodine in milk.
To treat benign conditions
Although radiation therapy is now mostly used to treat cancer, it was used to treat a number of benign (non-cancerous) diseases before the risks were clearer. Studies of these patients have helped us learn about how radiation affects cancer risk.
Peptic ulcer disease: A large study of people who were treated with high doses of radiation (an average of 15 Gy or 15,000 mSv) for the treatment of peptic ulcers found a higher risk of cancer of the stomach and pancreas.
Ringworm of the scalp: Studies of people who were treated with radiation to treat a fungal infection of the scalp (called scalp ringworm or tinea capitis) have found an increased risk of basal cell skin cancers. The risk was lower in people who were older when treated. This increased risk was seen only in white patients, and the cancers occurred more often in sun-exposed skin of the head and neck (as opposed to the scalp), which implies that ultraviolet (UV) radiation plays a role in these cancers as well.
Ankylosing spondylitis: Studies have looked at the cancer risks of patients with the autoimmune disease ankylosing spondylitis who were injected with a form of radium.
In one study, patients who received a high dose (average bone dose of 31,000 mGy) had an increased risk of bone sarcoma. The risks of some other cancers, such as breast, liver, kidney, bladder, and other sarcomas, may also have been increased. About one-quarter of the patients in this study were younger than 20 years of age when they were treated with radiation.
In another study, patients treated with a lower dose of radium (average bone dose of 6,000 mGy) had a higher risk of leukemia, but not of any other cancers. Most of the patients in this study were adults at the time of treatment.
Other studies: Treatment of the head and neck area with radiation for benign conditions has also been linked to cancers of the salivary gland and brain and spinal cord in adults in some studies. Children treated with radiation to this area also have an increased risk of thyroid cancer.
Studies have linked radiation therapy to treat cancer with an increased risk of leukemia, thyroid cancer, early-onset breast cancer, and some other cancers. The risk of cancer depends on a number of factors, include the dose of radiation, the part of the body being treated, the age of the person getting it (younger people are generally at greater risk), and the use of other treatments such as chemotherapy.
For example, people who get pelvic radiation therapy would not be expected to have higher rates of cancers in the head and neck because these areas weren’t exposed to the radiation from the treatment. Other factors might also play a role in how likely a person exposed to radiation is to develop cancer. For example, some genetic conditions can mean that a person’s cells are more vulnerable to radiation damage, which might in turn raise their risk more than in someone without these gene changes.
If cancer does develop after radiation therapy, it does not happen right away. For leukemias, most cases develop within 5 to 9 years after exposure. In contrast, other cancers often take much longer to develop. Most of these cancers are not seen for at least 10 years after radiation therapy, and some are diagnosed even more than 15 years later.
When considering radiation exposure from radiation therapy treatment for cancer, the benefits generally outweigh the risks. Overall, radiation therapy alone does not appear to be a very strong cause of second cancers. This is probably due to the fact that doctors try to focus the radiation on the cancer cells as much as possible, which means few normal cells are exposed to radiation. However, some combinations of radiation therapy and chemotherapy are more risky than others. Doctors do their best to ensure the treatment that is given destroys the cancer while limiting the risk that a secondary cancer will develop later on.
Some studies have estimated the risk of radiation exposure from imaging tests based on the risks from similar amounts of radiation exposure in the studies of the atomic bomb survivors. Based on these studies, the US Food and Drug Administration (FDA) estimates that exposure to 10 mSv from an imaging test would be expected to increase the risk of death from cancer by about 1 chance in 2000.
It can be difficult to study cancer risks from imaging studies that use radiation. In order to see small risks (such as 1 in 2000), a study would have to look at 10s or 100s of thousands of people. Information about other exposures that could be cancer risk factors would be needed, to see if it was likely that the cancer came from the radiation exposure. Since cancers from radiation take years to develop, the study would need to follow the patients for many years.
Often, scientists use questionnaire studies to look for possible causes of cancer. These studies compare exposures among people who have a certain cancer to those who don’t. They may instead compare people who had a certain exposure (like to radiation) to those who didn’t. However, this is difficult to do for diagnostic radiation exposure since many people cannot accurately recall information about things that happened many years before (such as in childhood) and information about all the imaging tests that were done is often not available. There is also a concern that people with cancer tend to over report exposures that they worry may have caused their cancers.
Studies that have found increased risk of cancer after imaging tests that use x-rays often involve people who had multiple tests or high dose procedures, including:
Studies of women who had been imaged many times with fluoroscopy as a teenager or young woman during treatment for tuberculosis have found an increased risk of breast cancer years later.
Teenagers and young women who had many x-rays of the spine to monitor scoliosis have been found to have an increased risk of breast cancer later on.
A study compared a group of people with meningioma (a brain tumor that is most often benign) with a group without the tumors. It found that the people who had the tumors were more likely to have had a type of dental x-ray called a bite-wing, and to have had bite-wing or Panorex x-rays every year.
A study in England of exposure to radiation from CT scans found that children who received a dose of at least 30 mGy (the same as 30 mSv) to the bone marrow had 3 times the risk of leukemia compared to those who received a dose of 5 mGy or less. For brain tumors, a dose of 50 mGy or more to the brain was linked to more than 3 times the risk.
A study in Australia of exposure to radiation from CT scans in childhood and adolescence found that after an average of about 9 ½ years, those who had a CT scan had a 24% higher risk of cancer overall. The risk of cancer was higher the more CT scans the person had, and it was also higher the younger the person was at the time of the CT scan. Still, the overall risk of cancer was still low.
A study from Taiwan found that children and teens who had a CT scan of the head did not have a higher risk of brain cancer or leukemia, but were more likely to be diagnosed with a benign brain tumor.
The Worsening Cosmic Ray Situation
March 5, 2018: Cosmic rays are bad–and they’re getting worse.
That’s the conclusion of a new paper just published in the research journal Space Weather. The authors, led by Prof. Nathan Schwadron of the University of New Hampshire, show that radiation from deep space is dangerous and intensifying faster than previously expected.
The story begins four years ago when Schwadron and colleagues first sounded the alarm about cosmic rays. Analyzing data from the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument onboard NASA’s Lunar Reconnaissance Orbiter (LRO), they found that cosmic rays in the Earth-Moon system were peaking at levels never before seen in the Space Age. The worsening radiation environment, they pointed out, was a potential peril to astronauts, curtailing how long they could safely travel through space.
This figure from their original 2014 paper shows the number of days a 30-year old male astronaut flying in a spaceship with 10 g/cm 2 of aluminum shielding could go before hitting NASA-mandated radiation limits:
In the 1990s, the astronaut could spend 1000 days in interplanetary space. In 2014 … only 700 days. “That’s a huge change,” says Schwadron.
Galactic cosmic rays come from outside the solar system. They are a mixture of high-energy photons and sub-atomic particles accelerated toward Earth by supernova explosions and other violent events in the cosmos. Our first line of defense is the sun: The sun’s magnetic field and solar wind combine to create a porous ‘shield’ that fends off cosmic rays attempting to enter the solar system. The shielding action of the sun is strongest during Solar Maximum and weakest during Solar Minimum–hence the 11-year rhythm of the mission duration plot above.
The problem is, as the authors note in their new paper, the shield is weakening: “Over the last decade, the solar wind has exhibited low densities and magnetic ﬁeld strengths, representing anomalous states that have never been observed during the Space Age. As a result of this remarkably weak solar activity, we have also observed the highest fluxes of cosmic rays.”
Back in 2014, Schwadron et al used a leading model of solar activity to predict how bad cosmic rays would become during the next Solar Minimum, now expected in 2019-2020. “Our previous work suggested a ∼ 20% increase of dose rates from one solar minimum to the next,” says Schwadron. “In fact, we now see that actual dose rates observed by CRaTER in the last 4 years exceed the predictions by ∼ 10%, showing that the radiation environment is worsening even more rapidly than we expected.” In this plot bright green data points show the recent excess:
The data Schwadron et al have been analyzing come from CRaTER on the LRO spacecraft in orbit around the Moon, which is point-blank exposed to any cosmic radiation the sun allows to pass. Here on Earth, we have two additional lines of defense: the magnetic field and atmosphere of our planet. Both mitigate cosmic rays.
But even on Earth the increase is being felt. The students of Earth to Sky Calculus have been launching space weather balloons to the stratosphere almost weekly since 2015. Sensors onboard those balloons show a 13% increase in radiation (X-rays and gamma-rays) penetrating Earth’s atmosphere:
X-rays and gamma-rays detected by these balloons are “secondary cosmic rays,” produced by the crash of primary cosmic rays into Earth’s upper atmosphere. They trace radiation percolating down toward our planet’s surface. The energy range of the sensors, 10 keV to 20 MeV, is similar to that of medical X-ray machines and airport security scanners.
How does this affect us? Cosmic rays penetrate commercial airlines, dosing passengers and flight crews so much that pilots are classified by the International Commission on Radiological Protection as occupational radiation workers. Some research shows that cosmic rays can seed clouds and trigger, potentially altering weather and climate. Furthermore, there are studies ( #1, #2, #3, #4) linking cosmic rays with cardiac arrhythmias in the general population.
Cosmic rays will intensify even more in the years ahead as the sun plunges toward what may be the deepest Solar Minimum in more than a century. Stay tuned for updates.
Schwadron, N. A., et al (2014), Does the worsening galactic cosmic radiation environment observed by CRaTER preclude future manned deep space exploration?, Space Weather, 12, 622–632, doi:10.1002/2014SW001084.
Schwadron, N. A., et al (2018), Update on the worsening particle radiation environment observed by CRaTER and implications for future human deep-space exploration, Space Weather, doi: 10.1002/2017SW001803.
Cosmic Ray Effect on Our Sun and Earth’s Core
The latest evidence based on NASA’s Jet Propulsion Laboratory research suggest the escalation of earth changing events such as earthquakes, volcanoes, and various extreme weather events are caused by natural cyclical oscillations of Earth’s core produced by an increase of cosmic rays charged particles.
Fluctuation of heating and cooling cycles on our planet are driven by exchanges of energy between the Earth’s atmospheric surface winds (jet stream), its ocean currents, and the Earth’s core process of convection. Scientists are now better equipped to measure small changes in Earth’s temporal and spatial orientation using astronomical and geometric observations.
Recent studies suggest changes in atmosphere and oceans are due to the flow of liquid iron within Earth’s outer core, where Earth’s magnetic field originates. This fluid interacts with Earth’s mantle to affect Earth’s rotation. While scientists cannot observe these flows directly, they can deduce their movements by observing Earth’s magnetic field.
Previous studies have shown that this flow of liquid iron in Earth’s outer core oscillates, in waves of motion that last for decades with timescales that correspond closely to long-duration variations in Earth’s climate. With new spacecraft monitoring our Sun and further beyond our solar system into our galaxy Milky Way – recent observations of charged particles such as galactic cosmic rays, gamma rays and solar winds influx coincide with Earth’s weakening magnetic field.
Researchers have found that Earth’s rotation, along with movements in Earth’s core and global surface air temperature corresponds to solar variance. Scientists mapped existing data from a model of fluid movements within Earth’s core and data on yearly averaged temperature observations against two time series – one from NASA’s Goddard Institute of Space Studies in New York that extends back to 1880, and another from the United Kingdom’s Met Office that extends back to 1860.
Observations found that temperature data correlated strongly with movements of Earth’s core disrupting Earth’s magnetic field which shields Earth from charged particles such as cosmic ray flux. Simultaneously, solar flares and CMEs coming from the Sun might provide a multiplying effect which has been evidenced in our history on at least six occasions concluding in full magnetic flip.