March 14, 1967

Memorandum to the Space Board of the National Academy of Sciences. Submitted to H. H. Hess, Chairman. On Radioactivity Hazards on Moon and Mars.

In view of the fact that landing of astronauts on moon is planned for only a few years from now, I submit this memorandum to draw the attention of the Board and also of NASA to a special condition the astronauts most certainly will meet on the Moon that may to a great degree invalidate the effort and its usefulness, and endanger the lives of the astronauts even if they succeed in returning. The cosmic rays hitting the Moon, solar plasma, and other incoming radiation are thought of, but one more source of radioactive hazard needs to be met.

Because of the intensity and multiplicity of the interplanetary bolts to which the Moon was subjected only 27 and 35 centuries ago (as described in Worlds in Collision) radioactivity must still be present on the surface of the Moon in quantity damaging to unprotected man or animal and by far exceeding any exposure regarded as safe.

Although the heat in the Moon’s subsurface is mostly a residue of the effects of disturbance in the Moon’s motions that occurred in the same historical periods, some of the heat is also of radioactive origin. The half-life of radium being 1580 years, enough radiation could be present on the Moon of this and other radioactive decays to prompt me to express this warning.

About four years ago, I drew the attention of Professor C. Pittendrigh to the danger of back-contamination, whereas then only the problem of micro-organic contamination of planetary bodies occupied the scientific advisers to space probes; not long thereafter the problem of back-contamination was discussed by Pittendrigh and others in committees and became a vital issue.

Everything that is said above of the radioactive perils to unprotected life on the Moon is applicable in the same degree to the future efforts to place man on Mars. Only on Mars, one should reckon with the probability of the presence of pathogenic, to man, micro-organisms, as well.

Of the many “craters” on the Moon, some with raised rims and with no rills radiating from them were in my understanding formed while, in cosmic disturbances, the surface of the Moon became molten and boiled (Worlds in Collision, p. 361). The subsequent discovery of domes or unburst bubbles confirms this understanding of the processes that created many of the craters.

“Craters” with rills radiating from them could be caused by infall of asteroids; granted that such a process also took place, I wish to stress that interplanetary discharges must have created a large number of such formations.

A landing of man on the Moon must be preceded well in advance by careful examination of the radioactivity on the Moon’s surface. The source described here is of equal importance, or possibly even of greater, than the effect of cosmic or other incurrent radiations on unprotected organic life. The required measurements must be made, not from orbiting space probes but by landing vehicles with instrumentation designed to detect various forms of localized sources of radiation.

(signed) Im. Velikovsky