MANNED SPACE FLIGHT

continued on improved digital television display equipment as well as on a Communications, Command, and Telemetry System automatic computer restart system.

During this period, the spacecraft-TV scan converter project was completed as were the prototype Digital TV Display System improvements which provide for an efficient means to produce background and reference slides. Work continued on the computer aided communications analysis system which provides real-time predictions of spacecraft communications performance; only the final checkout and demonstration test of this system remained. A color projection TV system was procured, tested, and installed in the MCC.

In the Communications system testing, the Apollo Communications System command module and lunar module detailed tests were completed as were numerous individual component and special tests. Lunar landing communications simulation was started, and overall system performance evaluation tests, anomaly resolution, and problem investigation continued.

Launch Information Systems (KSC)

Launch Information Systems at KSC is composed of Launch Instrumentation Systems and Operational Communications. Launch Instrumentation Systems are the meteorological, acoustic, hazard monitoring, lightning warning, telemetry, display, data recording, and computing systems used during prelaunch tests, countdown, and launch of space vehicles at KSC.

The primary effort was supporting the checkout and launch of Apollo 9 and 10 and the prelaunch testing of Apollo 11. Several system improvements were completed. Special recertification equipment was installed to erase and test magnetic tape for reusability; digital tapes were being recertified at a rate of approximately 2,000 per month. NASA added mass storage equipment to certain computers to permit mass storage of telemetry measurements for recall and determination of test measurement trends. The Agency also procured data quality evaluation equipment to evaluate the telemetry ground station (date-core)-to-computer data interface. Such evaluation serves as an aid in software checkout and rapid troubleshooting if a failure occurs during operational periods.

The Operational Communications include voice, data, television, and timing systems used for prelaunch test and launch support. These systems successfully supported the Apollo 9 and 10 launches and prelaunch testing of Apollo 11. The only major communica

tions equipment addition was a second (backup) operational television control console in the LC-39 Launch Control Center.

Because of the magnitude and complexity of the prelaunch voice communications system in the launch area, KSC was assigned an overall technical and management coordination role. Numerous interfaces between ground stations, consoles, and the spacecraft are involved in this highly critical system. The improved quality of voice communications in Apollo 9 and 10 demonstrated that this new approach was highly successful.

Huntsville Operations Support Center (MSFC)

The Huntsville Operations Support Center provided realtime consultative support to KSC during prelaunch and launch operations of Apollo 9 and 10. It also provided real-time support to the Houston Mission Control Center during the flight operations. The new 10-channel digital-to-TV display system which was installed late in 1968 became operational and supported both Apollo 9 and 10.

SPACE MEDICINE

NASA was designated as the responsible agency within the Federal Government for protecting the earth against harmful contamination from personnel or equipment exposed to extraterrestrial environments. (Federal Register, Vol. 34: No. 1313, July 16, 1969.) Within NASA, that responsibility was redelegated to the Director of Space Medicine. As the responsible authority, and in cooperation with the Departments of Health, Education, and Welfare, Agriculture, and Interior, he would determine the beginning, duration, and termination of quarantine. He would also authorize the actual release of lunar-exposed persons, property, and geological samples.

The Lunar Receiving Laboratory (LRL), begun in 1966 at the Manned Spacecraft Center, was completed and certified. Focal point for the Lunar Sample Program, LRL provides quarantine, medical, and physical science facilities. The Interagency Committee on Back Contamination (ICBC) certified that the LRL was in operational readiness. The ICBC is composed or representatives of the Departments of Agriculture; Interior; Health, Education, and Welfare; the National Academy of Sciences; and NASA. As a basis for certification, biological procedures developed or approved by the ICBC both for quarantine and release of the astronauts were tested and validated prior to the Apollo 11 mission.

2

SCIENTIFIC

INVESTIGATIONS

IN SPACE

The variety, number, and complexity of the unmanned spacecraft launched during the first six months of this year to carry out scientific experiments in space promised investigators an unprecedented return of data in the future. Some of the invaluable information already received by experimenters about the sun, the moon, the stars, the earth and its neighboring planets, and the regions surrounding them is outlined here.

PHYSICS And ASTRONOMY PROGRAMS

Four spacecraft were orbited in the physics and astronomy programs: Orbiting Solar Observatory-V (OSO-V) on January 22; the cooperative Canadian-American ISIS-I January 30; Orbiting Geophysical Observatory-VI (OGO-VI) June 5; and an Interplanetary Monitoring Platform (IMP-G, Explorer XLI) June 21. Orbiting Observatories

Similar in design and orbit to earlier spacecraft in the series, the 641-pound OSO-V satellite is made up of a rotating wheel to spin-stabilize the craft and a "sail" section that points at the sun. Its circular orbit at an altitude of about 350 miles-places the instruments on board above the earth's atmosphere.

On the "sail" are a British X-ray spectroheliograph built by the University College in London and the University of Leicester; a Naval Research Laboratory spectroheliograph made to study the ultraviolet portion of the solar spectrum; and a spectrometer from the Goddard Space Flight Center to investigate the solar spectrum from 1 to 400 angstroms. The rotating wheel carries five experiments, including an experiment from the University of Paris to

monitor solar hydrogen and deuterium, and photometers from the Naval Research Laboratory to observe solar X-ray flux.

In other experiments Goddard Space Flight Center was monitoring solar and stellar gamma rays of low energies (5 to 150 Kev); the University of Minnesota measuring dim light coming from space at 90° to the earth-sun line; and the University of Colorado investigating solar radiation in far ultraviolet bands (280 to 370, 465 to 630, and 750 to 1,030 angstroms.)

OSO-V detected previously unobserved solar flare omissions which will help scientists understand disturbances in the ionosphere. It discovered that the red airglow of the earth (whose source is unknown) reaches an altitude of 300 miles and ends abruptly. Also, other data transmitted by the spacecraft indicated that earth's upper atmosphere may contain ten times as much deuterium as estimated.

OGO-VI, the last of the Orbiting Geophysical Observatories, like the others, carries many coordinated experiments. It resembles a six-foot box with appendages whose wings of solar cells give it the appearance of an insect. Stabilized in three dimensions, the 1,400 pound spacecraft keeps one of its faces in view of the surface of the earth. It is one of the POGOS-Orbiting Geophysical Observatories positioned in low polar orbits to study geophysical phenomena near the earth.

The 25 experiments of OGO-VI investigate latitude-dependent atmospheric phenomena during a period of maxmium solar activity. They study atmospheric and neutron densities; electron density and temperature, and electrons trapped in the Van Allen belts; neutral atmospheric composition; ion concentration and mass; auroral particles and auroral and airglow emissions; magnetic and electric fields; VLF radio emissions; solar ultraviolet, solar cosmic, and solar X-rays; and galactic cosmic rays.

Seventy-nine of the 130 experiments aboard five operational OGOS in orbit (including OGO-I launched in 1964) continued to provide data. Analysis of a fraction of the data has supplied new information on the earth's magnetosphere and its shock fronts, on auroral phenomena, and on atmospheric chemistry on a global scale.

OAO-II (launched December 7, 1968) demonstrated that astronomical observations must be extended from the visible region to the invisible ultraviolet region of the spectrum to understand stellar phenomena. For example, the satellite observed that some galaxies radiate more strongly (are "hotter") in the ultraviolet. Therefore, the basic relationships for estimating stellar distances may

have to be revised, since a crucial star's temperature would have to be revised.

OAO-II also disproved the theory that much of the mass of the Milky Way was composed of molecular hydrogen that radiated in the ultraviolet, and found that the night sky-outside of this galaxy-was not as bright as assumed, proving that there was much less luminous matter in the universe than scientists had believed. Explorer XLI

Explorer XLI, IMP-G, is another of the Interplanetary Monitoring Platforms which investigate the earth's environment and monitor radiation in space (figs. 2-1 through 2-3). The 174-pound IMP-G is in a highly elliptical orbit reaching about halfway to the orbit of the moon. It carries 12 experiments from universities and industry, and one from Goddard Space Flight Center, which study cosmic rays, solar wind, and the interplanetary magnetic field. The studies provide data vital for spacecraft design and essential in planning future space missions.

ISIS-I

ISIS-I is the first of the Canadian-American satellites to follow