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PopSci illustration of trajectory to the moon. This is denied by Apollo astronauts.
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Earth’s radiation belts versus science media.
Ever nice NASA launched Explorer 1 into space in 1958 and proved that Earth did have a magnetosphere to protect from deep space radiation and solar winds, it has remained bound in conflicting ideas and evidence. One side says it is an impediment to space travel unless measures are taken to properly shield space vehicles and crews; the other side (mostly 1960’s astronauts) says there is little harm from trapped radiation in the belts. A third group, the moon hoaxers, suggest that the easy passage of Apollo crews with minimal shielding is evidence one of many elements of a hoax.
It doesn’t help matters that science web sites post conflicting statements regarding this issue.
Take this example in a Space.com article by Elizabeth Howell entitled, Van Allen Radiation Belts: Facts & Findings:
The astronauts on the ISS do not regularly spend time inside the belts, but from time to time solar storms expand the belts to the orbit of the space station. In the 1960s, several Apollo crews went through the Van Allen belts on their way to and from the moon. Their time in that radiation-intensive region, however, was very short, in part because the trajectory was designed to pass through the thinnest known parts. With more study, astronauts can be better protected for long-term stays in Earth orbit.
Now examine the following statement by Frank Borman, commander of Apollo 8, in his book Countdown:
“Slightly less than five hours after lift-off, we passed through the Van Allen radiation belt, and Anders transmitted our personal radiation dosimeter (PDR) readings. Even in the thickest part of the belt, they showed we were receiving about the same dosage we’d get from a chest x-ray. So much for the dire predictions some scientists had made about harmful, perhaps fatal, exposure to the belt.”
Because of this example, Howell has called Borman a liar in her article. He is clearly stating that they went straight through the radiation belts in an apparent straight line and in the thickest (densest) part as well, with minimal radiation exposure. No fancy flying was done to get to the moon! Borman also got a mild dig in at Dr. James Van Allen, the discoverer of the belts, who was a leading proponent of health hazards while traversing the magnetosphere.
(Also mentioned in Apollo 8, Borman, Kluger, p. 186-187.)
It should be noted that this issue with trajectory, as seen in the illustration from popsci.com above, showing an elliptical path to avoid the more dangerous areas of the belts, is common among science news web sites. And once again, contradicts the experiences of the astronauts as described by Frank Borman. In the books by the other Apollo astronauts describing their journeys (Armstrong, Borman, Collins, Cernon, Lovell, Shepard), the Van Allen Belts are rarely mentioned, and if so, never in context with their experiences of space travel. The same applies to the voice transcripts available at NASA.gov.
It is worth noting that the Apollo astronauts were not the first to pass into the Van Allen belts. The Gemini astronauts also traveled into the belts in 1966. Michael Collins in his book Catching the Fire, flew in Gemini 10 and writes of achieving a record altitude of 475 miles. That puts him and fellow astronaut John Young well within the first belt. Any radiation exposure problems? No. And they were followed up by Gemini 11 (Pete Conrad & Richard Gordon Jr.) in the same year, with an altitude of 850 miles. Even deeper into the Van Allen belts. No radiation issues with them either.
In Summary
It seems that the issue of the Van Allen radiation belts is a muddy mess to wade through. It involves constantly changing data and conflicts between what is really out there and the personal effects on the astronauts. Pursuing space research on these issues is difficult due to a consensus on the exact nature of the data. There are conflicts involving the size and depth of the radiation belts, the exact distance between the moon and the earth, the precise surface temperatures on the moon and so on.
The astronauts, both Gemini and Apollo, experienced no ill effects when passing thru the belts. There is no need for the elliptical trajectory in the illustration above and the there is no documentation of them doing this, nor do the astronauts state in their books that they completed a trajectory like this. They speak of the “free return trajectory” where they complete several orbits and then fire the remaining booster for a final burn to escape the earth’s gravity to slingshot their way to moon. Free, as using no fuel for the cislunar flight path. It’s a beeline. This is very important because if the burn does not provide enough escape velocity, they sling off into space and miss the moon.
If what Frank Borman said is true, the dangers of the radiation belts are vastly over rated. Just a chest x-ray, albeit one that lasts for two hours. Make that two x-rays since they had to pass back through them on the way back home. Future astronauts will wear a vest to protect them radiation exposure. Interesting that the astronauts of the 1960’s didn’t need one.
The Orion project for travel to the moon and beyond, is a reengineering of the Apollo hardware since most the technology has been lost, erased or destroyed, which is a great mystery unto itself.
Sources
Van Allen radiation belts article at Space.com
Likewise at Popular Science:
Michael Collins, Carrying The Fire, p. 216
Frank Borman, Countdown, p. 203-204
Apollo 8, Frank Borman with Jeffrey Kluger, p. 186-187.
