SID: THE SOLAR RADIATION ENVIRONMENT DURING SOYUZ 3 AND FUTURE M

Created: 2/1/1969

OCR scan of the original document, errors are possible

SCIENTIFIC INTELLIGENCE DIGEST

Boorot

9

THE SOLAR RADIATION ENVIRONMENT DURINGND FUTURE MANNED FLIGHTS

greatest series of solar flares in Ihe presenl solar cycle occurred during andafter theannedctober. The Soviets were aware of this solar activity and evidenced interest and concern in monitoring the radiation levels duringBcregovoy's flight. Since the spacecraft was within theagnetic field, however, there /was little danger for the cosmonaut duringlight. It is believed that the radiation levels inside the spacecraft did not exceed the safe limits and that the solar activity did not necessitate an early recovery of Soyuzhere Is no evidence that extravehicular activity (EVA) was planned for theission but it is doubtful that such activity would have been attemptederiod of unusually high radiation.

Solar particle radiationazard to cosmonauts on manned space missions and therefore the timing of future missions will be affected by the level of solar flare activity. The danger can be severe if the cosmonaut ts outside of the earth's magnetic field at the limeolar proton event, but it can be reduced by the spacecraft shielding and by keeping thewithin Ihe earth's magnetic Held.

Onctober, the dayas launched, the initial signs of upcoming solar flare aclivity were noted by Ihe US forecastapid sequence of small flares occurred fromoctober. These disturbancesery large amount of radio noise but did not include any proton events. This series was the prelude to the major flare which occurred the nextctober) just after thead reentered the earth'sThis flare was ofthe worst possible solar flare event is Importancend during the next severalcries of large solar flares Included two of Importancehis high level of solar flare activity continued for several days. Proton events were associated with the activity which began onctober.

The Soviets commented onctober that astrophysical observatories and geophysicalin the USSR had registered an increase in solar activity. The flare ofas noted by the astronomers at the Ussunysk Astronomical Observatory; they said thatowerful flare had not heen observed for seven years. The Soviets stated that solar radiation levels measured inside the spacecraft had not exceeded safe limits.

69

SECftET

protection offered by the Soviet spacecral the limiting effect of the earth's atmosphere and geomagnetic field on solar protons and alpha particles wouldafe radiationfor the cosmonaut in.idc the spacecraft.

Since the solar maximum ofyear solar cycle is due. solar flare activity will have an important bearing on the timinganned mission, especially those involving EVA activity in earth orbit or on the lunar surface. If the Sovietspacecraft for lunar landing with minimum shielding such as the US lunar module, the occurrencearge proton event while the craft is on the lunar surface would be critical lo mission success. The space-suit would not afford adequate piotectionosmonaut on the lunar surfaceroton event. EVA in earth orbit probably would be scheduled to avoid such events. The command spacecraft probably would provide enoughfor the cosmonaut on earth orbital and lunar missions.

Collection of solar data from scientificfor the USSR is administered by IZM1RAN (Institute of Terrestrial Magnetism. Ionosphere, Radiowavehe USSR is seeking to achieve round-the-clock monitoring capabilities and is interested inorld-wide warning network. Neither has been achieved. New and improved methods forsolar flare activity by using information on the solar magnetic field and sun spotare being developed under the direction of Dr. A. B. Severney at the Crimean Astro-physical Observatory. No real-time solarcapability is anticipated in the foreseeable-future. H

69

Original document.

---

---