Radiation ‘Storm Cellar'

Press, Volume CVIII, Issue 31866, 19 December 1968, Page 20

Radiation ‘Storm Cellar '

HOUSTON, Dec. 17. The Apollo 8 moonship will serve as a radiation “storm cellar” to protect its three pilots on their Christmas flight round the moon, United Press International reports.

Radiation is the only significant hazard in the space environment penetrated on the moon flight that is not encountered in earth orbital voyages. But officials say it is nothing to worry about for Apollo 8. The radiation comes primarily from the sun, in low energy flows and in occasional outbursts of far greater intensity from great thermonuclear disturbances called solar flares. In earth orbital flight,

radiation has not been much of a problem because all manned spaceflights to date have remained inside a protective shield of magnetic forces that surround the globe. This magnetosphere repels most high-energy radiation emanating from the sun and beyond. These magnetic forces, however, also trap radiation particles in zones high above I earth called the Van Allen (radiation belts. Man has not ;yet penetrated these areas. I But on moon flights, spaceships will fly through the Van Allen belts and beyond the protective envelope of the magnetosphere. Once outside this magnetic shield, a spacecraft has no protection against dangerous radiation other than its own skin and structure. “We have a great deal of information, all that we believe we need to understand the radiation environment of the earth-moon system,” said Lieutenant-General Samuel Phillips, the Apollo programme director. “These radiation environments have been taken into account in the design of our equipment.” “The command module, for example, provides a very; good shield against radiation,” he said.

The Apollo 8 astronauts, Colonel Frank Borman, ' Captain James Lovell and i Major William Anders, will 1 remain inside their command | ship throughout the flight. ,

“I think you must remember,” Major Anders told a reporter at a recent news conference,” that the command module is a relatively thick-skinned vehicle and offers a very good so-called storm cellar in the event we should chance upon a very unusual flare.” Dr Charles Berry, the chief astronaut physician, said he expects the three astronauts to receive a total radiation dose during their six day flight equal to the radiation received with a hand X-ray. If a severe solar flare

should catch the astronauts (off-guard, the radiation dose | expected would increase tre- , mendously—up to something I like the total dose received from 15 full mouth dental i X-rays. ■ If the dosages were twice as bad as the estimates expected in the worst possible case, Dr Berry said the astronauts might receive some temporary skin reddening and' some decrease in white blood : cells. “Neither of these things) would worry us,” Dr Berry' said. [ Basing his view on I ! statistical estimates, Dr Berry I said such a severe radiation j dosage could decrease the astronauts’ life span by something like 300 days, just as every X-ray could shorten a person’s life span. But this kind of estimate. Dr Berry said, “is a very questionable thing.” “I think what this all adds up to is that I wouldn’t have any concern whatsoever about this mission,” he said.' Major Anders said, however, that if a severe solar l flare were expected or had I occurred, the mission might! be delayed. “But this would ( have to be a pretty big flare i to slow us down too much." j For later moon missions. I however, radiation will play! a bigger role in plan-1 ning. The thin - skinned! lunar module moon-land-ing craft offers only onethird the protection provided by the command I

module, and when an astronaut is alone on the moon's surface, he has virtually no shielding. The United States has a network of ground and space sun monitoring stations and these are expected to warn astronauts of impending dangers in time to allow them to return to the safety of the command ship. ! The United States launched [one of these radiation watchers on November 8, I into orbit around the sun (The spacecraft. Pioneer 9. j joined three others in providing daily reports on I solar flares. By being able to observe the sun from all directions, the pioneers can detect solar flares before the sun s rotation points their radiation toward the earth and moon. Pioneer 6, launched three years ago, is now 164 million miles from earth and can detect these solar flares 16 days before they face earth.