NATIONAL AERONAUTICSAND SPACE ADMINISTRATION

Washington, / 202-755-8370 FOR RELEASE: NovemSer 5, 1973 D. C. 20546

Third Manned PROJECT:SKYLAB 4

Mission

R
E
S

contents
GENERAL RELEASE .... I-5

OBJECTIVES OBJECTIVES

OF OF

THIRD SKYLAB

MANNED MISSION PROGRAM 1 .

..

.7-8 6 9-11

EXPERIMENTS COMET KOHOUTEK AND SKYLAB

13-23 24

ACCOMPLISHMENTS ....

REAL-TIME FLIGHT MISSION PROFILE

PLANNING

25-27 28-29

SKYLAB RESCUE VEHICLE

33

COUNTDOWN 30-32 NOTE: Details of the Skylab spacecraft elements, systems, crew equipment and experimental hardware are contained in the Skylab News Reference distributed to the news media. The document also defines the scientific and technical objectives of Skylab activities. This press kit confines its scope to the third manned visit to Skylab and briefly describes features of the mission.

NATIONAL AERONAUTICSAND SPACE ADMINISTRATION

D. C. 20546

202/755-8370

FOR R(LEASE:
Bill Pomeroy Headquarters, Washington, (Phone: 202/755-3114) D.C. November 5, 1973

RELEASE

NO:

73-229

SKYLAB

PUTS

OUT

WELCOME

MAT

FOR

COMET

Space orbiting

Station

Skylab's

final the

tenants Earth on

will or

move about

into

their

home

270 miles a harvest our life

above of

November about our

i0 to complete home planet and of

scientific star, the

information the S%In. station Two

giving

earlier 28 and final

threesomes 59 days crew

tsnants

occupied the key

space

for

before will

"leaving live

under

the mat"

for the

that

aboard

Skylab

for up to two months.

Earth experiments with bonus the

resources, will fill

solar the

astronomy, hours comet

medical of the

and Skylab

other crewmen, added

Waking the

opportunity or

to view January.

Kohoutek

as an

in December

Flying Skylab's to provide continuing dynamic

above

the

distorting and about of

layers

of

Earth cameras of

atmosphere, are expected as

solar

telescopes data

astronomical the the make-up flares, face

valuable the

comets

as well and

surveillance taking place

prominences Sun.

other

events

on the

of the

-2-

The manned

spacecraft's

crew can provide the sudden

fast reaction emergenc e and rapid

times in monitoring
development comet. based react of

and recording
events losing radio

unpredicted satellites, and in

Unmanned data as

valuable of

analysis quickly.

relay

information,

For experiments will

the

final -solar

Skylab

manned

mission

three

Categories and medical

6f -with

physics, set during

Earth the

resources first two data. comet

follow

patterns tasks Mount in

missions, The

additional Telescope vations resources additional to long increase periods in

gathering has its been

scientific assigned chores. options

Apollo obserEarth to I0

(ATM) to

Kohoutek 30 for been adapts up

addition surveys,are surveys. the of

other

Although are open have body

planned, Medical of

investigations how the human

broadened to

knowledge space

flight.

Other including Science high as an

corollary ten student

scientific experiments in

and

technological by the

experiments National among services

--

selected a nationwide out

Teachers

Association -will

competition final

school orbiting

students

round

Skylab's

scientific

station.

-more-

L 3-

A the in

scientific near and

highlight the Earth-Sun

for

the region

next of

Skylab the

crew

will Kohoutek

be

passage December

comet will on

January. (closest both

The

mission

period to Sun)

cover December behind comet

the 28, the

comet's allowing Sun as

perihelion observations well around as the and

approach before

Kohoutek changes deep space.

passes as the

post-perihelion retreats into

swings

Comet cal the

observations and for

will

be

made

with two

solar

and

astronomioutside an a a on

instruments ATM truss

cameras,

including by the

mounted during offers of the they

operation point above the

astronauts

EVA.

Skylab's opportunity ultraviolet comets, snowballs sumables to extend

vantage to

the changing is

atmosphere

unique comet in of giant the

observe

composition about that system. keep 70 open

spectrum. that the

Little popular the

known

structure are like conoption upon An for of ice

other

theory solar to

hurtling will the be

through closely

Skylab an

husbanded to about of

final the

mission condition

days, station an

depending systems.

crew

health of

and the

space

extension northern snow

mission winter and the

would Earth start

provide

opportunity surveys

hemisphere

resources of the

and

distribution

growing

season.

Crewmen science Marine pilot; Corps

are

Gerald

P.

Carr, R.

commander; pilot.

Dr. Cart

Edward is

G. a U.S.

Gibson,

and

William

Pogue,

lieutenant and Pogue in

colonel, a U.S. Air

Gibson Force

a civilian lieutenant

scientistcolonel.

astronaut, None has

flown

space. -more-

-4-

This ]]:41 Space will a.m.

liftoff, EST

designated i0

Skylab atop

4,

is IB

scheduled from NASA

for Kennedy and orbit docking after a

November I.aunch the

a Saturn 3Q, Pad B.

Center!s occur

Complex fifth

Rendezvous module

during rendezvous

command/service sequence.

standard

maneuver

After "turning of working

docking on" Skylab

with

the

space

station, for two

the

crew or

will more

begin

in preparation in space.

months

and

living

Undocking two-impulse module (310

for

56-day propulsion

mission

would

be

January

6 with

a co--and km

service

retrofire

sequence Pacific,

bringing about 509

splashdown statute miles) would is about be

_n

the

north-central of EST on

north-north-west at 5:44 to EST in 69 p.m. days,

Honolulu, January 6.

Hawaii. If be the on January

Splashdown mission 19 at

extended 4 p.m.

splashdown Pacific.

would

the

central

Like several before At

any defects

new --

home,

the

experimental -which for the had

space to be

_tation

had

anomalies habitable

corrected long missions. off, generating unfolding. station

Skylab an it

became aluminum one of

planned shield

launch, with

micrometeoroid the main solar other

ripped for

taking

cell to

arrays prevent the

electrical Loss to of the to

power shield an

and

jamming

the

its space

caused

temperatures hiqh level.

inside

rise

uncomfortably

-more-

--5--

The Kerwin which The first the

first Paul

crew

to

visit carried help array

Skylab, along the freed be

Charles

Conrad,

Joseph device

and they

Weitz, to cell

a parasol-like temperatures during an

erected solar visit of that in

bring was to

down. EVA nOt and only in conthe from

jammed manned

turned gathering men space0 can

out

successful, data,

standpoint

scientific take on

but

also

demonstrating struction jobs

difficult

repair

and

The work Jack one.

second the

Skylab space a a

crew

Was

not Alan

without Bean, to gyros

its Owen

share

of

repair an_ fir!st

around Lousma They

station. second

Garriott the

erected installed

sunshield of

supplement in gyros the

"six-pack" to replace

Skylab had

attitude become

control undependable.

system

balky

that

Two They was tion

repair

chores

are the

planned fluid in

for

the

final

Skylab

crew. loop that

include leaking of the in

replacing during antenna the the on

a primary manned

coolant mission;

second the

Skylab

and

inspec-

S193

Microwave Experiment

Radiometer/Scatterometer Package (EREP).

Altimeter

Earth

Resources

-6-

OBJECTIVES

OF

THE

SKYLAB

PROGRAM

The Skylab Program was established for four purposes: (a) to determine man's ability to live and work in space for extended periods; (b) to extend the science of solar astronomy beyond the limits of Earth-based observations; (c) to develop improved techniques for surveying Earth resources from space; and (d) to increase man's knowledge in a variety of Other scientific and technological regimes. Skylab, the first space system launched by the United States specifically as a manned orbital research facility, is providing a laboratory with features not available anywhere on Earth. These include: a constant zero gravity environment, atmosphere, Sun and space observation from and a broad view of the Earth's to the the use practical Skylab is of space for the human benefits the above the surface. Earth's

ledge tions

Dedicated and for can

increase of knowthat space operaobjectives:

bring,

pursuing

following

its the

Ph[sical influence universe.

science - Increase man's knowledge of the Sun, on Earth and man's existence, and its role in Evaluate from outside Earth's atmospheric environment of from the Milky near-Earth Way and

filter, the radiation and particle space and the radiations emanating remote regions of the universe. Life Science Increase man's of not

knowledge

of

the

physiolo-

gical and biological functions observations under conditions

living organisms by making obtainable on Earth. techniques areas of and water for observing agriculture, pollution, land

Earth Applications Develop Earth phenomena from space in the forestry, geology, geography, air use and meteorology. space Applications future space activities actions, structures and environments.

- Augment the technology base for in the areas of crew/vehicle intermaterials, equipment and induced

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-7-

OBJECTIVES

OF

THE

THIRD

MANNED

SKYLAB

MISSION

The third Skylab manned mission officially began September 25 when the second CSM and its crew separated from the space station just prior to reentry. The unmanned portion of this SL-4 mission wil_ continue until the third crew is launched. After docking, the crew will enter Skylab, reactivate its systems, and proceed to inhabit and operate the orbital assembly for _p to 56 days. During this time the crew will perform systems and operational tests and the assigned experiments. The objectives follows: Perform a. unmanned of the third Skylab manned mission are

as i.

SatUrn

Workshop

operations
performance of the

Obtain data for evaluating unmanned station. Obtain vations. solar astronomy data

the

b.

by

unmanned

ATM

obser-

2.

ReactiVate a.

_nd

Man

Sk_lab

in

Earth

orbit

Operate the cluster space structure for launch. Obtain data for space station.

(SWS plus CSM) as a habitable up to 56 days after the SL-4

b.

evaluating

the

performance

of

the

c.

Obtain data for evaluating crew capability in both intravehicular activity. medical of data on space the crew for

mobility and work and extravehicular

3.

Obtain duration a.

use

in

extendin

9 the

manned

flights the effects flight of up on to

Obtain medical data for determining the crew which result from a space 56 days duration. Obtain medical Skylab mission advisable. data for determining of greater duration

b.

if a subsequent is feasible and

-more-

--8--

4.

Perform a.

in-flight

experiments

Obtain ATM solarastronomy data for continuing and extending solar studies beyond the limits of Earthbased observations. Obtain Earth resources data for continuing multisensor observations from Earth orbit. Obtain data of of Earth-based the comet Kohoutek observations, beyond and extending

b.

c.

the f

llmits

d.

Perform the assigned scientific, nology and DOD experiments.

engineering,

tech-

-more-

-9-

SKYLAB

EXPERIMENTS

The Skylab space station carries the largest array of experimental scientific and technical instruments the United States has ever flown in space, a total of 58. They fall into four general categories: life sciences, Earth resources, solar physics and corollary. Data received will permit 200 principal investigators to supervise 271 scientific and technical investigations. While most of the detailed experiment runs are planned pre-mission, there are occasions when specific observations are scheduled in real-time to take advantage of unique opportunities such as solar flares and hurricanes observed during the first and second mission. Skylab medical experiments are designed man's ability to live and work in space for his responses and aptitudes in zero gravity, to readapt to Earth gravity once he returns to measure extended periods, and his ability to a one-g field.

Earth resources experiments (EREP) employ six devices to advance remote-sensing technology and at the same time gather data applicable to research in agriculture, forestry, ecology, geology, geography, meteorology, hydrology, hydrography and oceanography through surveysof site/task combinations such as mapping snow cover and water runoff potentials; mapping water pollution; assessing crop conditions; determining sea state; classifying land use; and determining land surface composition and structure. On days that EREP passes are scheduled, the JSC News Center will publish site/task guides identifying principal investigators, specific locations or areas and scientific disciplines. The third manned mission has 30 EREP passes scheduled with possible options for up to 10 more, including passes over the United States, South America, Europe, Africa, Australia/New Zealand, Malaysia and Japan. An extension to a 70-day mission duration would allow coverage of snow and ice distribution in the northern hemisphere and the start of the growing season in the United States. ATM solar astronomy experiments utilize an array of eight telescopes and sensors to expand knowledge of our planet's Sun and its influence upon the Earth. Additionally, ATM instruments will be used in observations of the comet Kohoutek between December 14 and January 2 and other non-solar events such as the planet Mercury's transit and a solar eclipse.

-more-

-i0-

A wide range of experiments category, ranging from stellar processing in zero-g to further

falls into the corollary astronomy and materials evaluation of astronaut

maneuvering devices for future extravehicular operations. Several instruments in the corollary category will also be used in observations of the comet Kohoutek, as will a new experiment, $201, a modified version of an instrument taken to the Moon on Apollo 16. Ten Association the Skylab mission. experiments through Student selected a national Project are by the National school to the Science Teachers in

secondary assigned

competition third manned

are

Experiments assigned listed below: medical Mineral

to

the

third

manned

Skylab

mission

In-flight M071 M073 M074 M092 M093 MII2

experiments Balance

(on

all

missions):

Bioassay of Body Fluids Specimen Mass Measurement Lower Body Negative Pressure Vectorcardiogram

Mll3
MII4_ MII5.) M131 M133 MISI MI71 M172 Hematology and Immunology Human Vestibular Function Sleep Monitoring Time and Motion Study Metabolic Activity Body Mass Measurement (These are two ground-based M078 and Mlllinvolving Experiment Package

medical preand (EREP)

experiments post-flight (on

data.) all

Earth Resources missions): sIg0A SI90B S191 S192 S193 S194

experiments

Multispectral Earth Terrain

Photographic Camera

Cameras

Infrared Spectrometer Multispectral Scanner Microwave Radiometer/Scatterometer L-Band Radiometer

and

Altimeter

-more-

-ii-

The S052 S054 S055A s056 S082A S082B

ATM

experiments

(on

all

missions):

White Light Coronagraph X-Ray Spectrographic Telescope Ultraviolet Scanning Polyohromator-Spectroheliometer Extreme Ultraviolet and X-Ray Telescope Coronal Extreme Ultraviolet Spectroheliograph Chromospheric Extreme Ultraviolet Spectrograph (Two hydrogen-alpha telescopes are used to point the ATM instruments and to provide TV and photographs of the solar disk.) corollary experiments:

The D024 M479 M487 M509 M516 M556 M566 S009 s019 S020 S063 S149 S183 S201B S228 S230 S233 T002 T003 T020 T025 T053 The

Thermal Control Coatings Zero Gravity Flammability Habitability/Crew Quarters Astronaut Maneuvering Equipment Crew Activities/Maintenance Study thru Multipurpose Electric Furnace Experiments Nuclear Emulsion Experiment uv Stellar Astronomy X-Ray/Ultraviolet Solar Photography uVAirglow Horizon Photography Particle Collection UV Panorama Far UV Electronographic Camera Trans-Uranio Cosmic Rays Magnetospheric ParticleComposition Hand-held Photography of Comet Kohoutek Manual Navigation Sightings Inflight Aerosol Analysis Foot-Controlled Maneuvering Unit Coronograph Contamination Measurements Earth Laser Beacon student investigations:

EDI2 ED22 ED24 ED25 ED31 ED41 ED61/62 ED63 ED72 ED76

Volcanic Study Objects within Mercury's Orbit X-Ray Stellar Classes X-Rays from Jupiter Bacteria and Spores Motor Sensory Performance Plant Growth/Plant Phototropism Cytoplasmic Streaming Capillary Study Neutron Analysis

(Details of most of the above experiments may be found in Skylab Experiments Overview, available from the Government Printing Office (Stock No. 3300-0461) $1.75/copy; or from experiment booklets and manuals in the KSC and JSC newsrooms.

SKYLAB 4 EREP PASSES

.BASELINE MISSION COVERAGE-----4," ! EXTENDED MISSION i OPTION COVERAGE 1 12/2 i UNITED STATES 12/11 I 12/25 t 1/6 i 1/15 il UNITED STATES*

SOUTH AMERICA i 11/16 11/22

i S. AMERICA

'

"tEUROPE i AFRICA
i11/3.0 _._ I I AUSTRALIA

1/2 "'

1/5 'AFRICA

_l'a

11/21 _.

1/2 12/11 ,A MALAYSIA _ _. NEW ZEALAND 1/6 JAPAN

NEW ZEALAND

*SEA AND ICE STUDIES SNOW DISTRIBUTION BEGINNINGOF GROWINGSEASON

, i

i ,

-13-

COMET

KOHOUTEK

AND

SKYLAB

An unanticipated major astronomical event has caused revisions in planning for the third and final Skylab manned mission, the SL-4 mission. The passage of the comet Kohoutek was detected early enough in its trajectory to permit scientists to plan ahead for the most promising means to explore its secrets. This will be an extraordinary, opportunity for cometary astronomers, intent on training the best instrtunents of 1973 on this exciting intruder. The special capability of Skylab rates crew and its instruments are, by good and able to respond, to obtain maximum comet. top priority. fortune, ready knowledge about Its the

Passing inside the Earth's orbit in late November, Kohoutek will travel through the inner solar system during a unique period in the space program, when Skylab and Mariner Venus-Mercury will be in operation and a new NASA C141 Airborne Infrared Observatory is ready for flight. Surprisingly little hard information is available on the physical nature o_ comets, despite recorded observations dating back to 467 B.C. Recent work indicates that the clues scientists microwave need exist regions of in the the ultraviolet, cometary spectrum. infrared, and

Comets are generally regarded as samples of primordial material from which the planets formed billions of years ago. Unlike Moo. _ Yocks and most meteorites which have experienced melting, the interiors of comet nuclei are believed to have remained in an icy state since their creation.

-more-

-14-

A great variety of striking phenomena occur in comets. A few comets actually have disappeared during relatively brief gaps in the observations. One comet split into two comets. A secondary tail apparently formed on another in response to the passage of an interplanetary shock wave. The appearance of a fine spiral pattern in the head of Comet Bennett has been attributed to rotation of the unresolved _.._leus. Earlier this year, a flare occurred comet, increasing its brightness by a factor i0,000 in six days. The most permanent feature of a comet, in a faint of almost

the

nucleus,

is believed to be a sort of dirty ice ball, consisting of frozen gases ("ices") and dust particles. In r_!_onse to solar radiation as the comet leaves the cold of deep space, the ices sublime and their vapors form an atmosphere, or coma, with a diameter that may reach 100,000 kilometers (60,000 statute miles). The estimated diameters of cometary nuclei range upward to only a few tens of kilometers or miles. According to one estimate, the nucleus of the Halley Comet loses about 3 meters (i0 feet) of surface material each time it passes the Sun. Kohoutek is probably similar in mass to Halley, but going much closer to the Sun, should shed much more. Separation and ionization due to solar photons and solar wind particles are among the processes which act on gases i_ t_e cc_, _roducing "daughter products" - the atoms, radicals, molecules and ions that have been detected spectroscopically in comets. Many astronomers believe that direct detection of the ices and their vapors - the so-called "parent molecules" has not been established. The gases observed thus far are all or mostly daughter products which are unlikely to exist in a solid state under the conditions prevailing in cometary nuclei. Dust particles liberated from the comet nucleus are impelled in the direction away from the Sun by the pressure of solar radiation. Ions produced in the coma are similarly affected by the charged particles in the solar wind. Thus are formed the dust and plasma tails, which can extend up to i00 million kilometers (60 million miles).

-more-

-15-

The dust tails typically look smooth, gently curved and yellow, while the plasma tail is straight, characterized by filaments and an often turbulent appearance and is blue. If comets condensed from the solar nebula in the

region where Jupiter formed, as many astronomers believe, then the parent molecules may be expected to include water, methane and ammonia. On the other hand, if the cometary ices represent aggreCated interstellar material, then many more complex substances, including formaldehyde and the other organic molecules that radio astronomers have found in galactic clouds and regions of presumed star formation, should be present. Hydrogen was first detected in comets a few yearJ ago, thanks to ultraviolet observations with the 0A0-2 and 0G0-5 satellites. These data showed that the hydrogen atoms occupied an enormous cloud, typically larger than the Sun, surrounding the visible coma. The origin of comets is unknown. of sources. At any rate, comets are into the inner solar system where we the long-period comets. Others have in small orbits. These short-period famous Halley which returns in 1986. in 1910. There may be a number occasionally perturbed see them briefly as been captured comets include the Halley was last seen

Kohoutek is at least, a long-period comet (10,000 80,000 years perhaps) and recent trajectory information the possibility that this is the first time that the comet has ever approached the Sun.

to raises

Because Kohoutek may be in a relatively undisturbed state, the possibility of obtaining especially valuable scientific information seems clear. To respond to this challenge, NASA has organized "Operation Kohoutek" to obtain physical data on the comet by every suitable means. Dr. Stephen P. Maran of the NASA Goddard Space Flight Center in Maryland is manager of Operation Kohoutek. The overall objective of Operation Kohoutek is to make a comprehensive investigation of the nature and evolution of th_ coma and tails as the comet approaches, passes and recedes from the Sun. Among the detailed goals are: -more-

-16-

i.

TO identify ("daughter

the parent molecules of the gases products") observed in comets; that break down the for_ the daughter radiation spectra;

2.

To determine the processes parent molecules and that products and excite their

3.

To determine the physical nature and causes of transient events in the comet and their relation to solar activity and phenomena of the interplanetary plasma; To measure the solar system; solar wind velocity in the inner

4.

5.

TO search for helium, deuterium, molecular hydrogen and other substances that have not yet been found in comets.

Why all the fuss about Kohoutek? From early observations and calculations it appears that Kohoutek is larger than average and will become extremely bright. This will facilitat_ measurements at very high spectral, spatial and time resolutions, providing maximum scientific data return. Thanks to Kohoutek's quite small perihelion distance from the Sun, observations of its interactions with the solar wind should reveal new facts about the charged particle environment well within the orbit of Mercury. As a new or long-period comet in a highly eccentric orbit, Kohoutek may differ substantially from comets such as Enuke and Hilley that remain within the planetary system, bounded by the orbits of the outer planets. The shortperiod comets spend a greater fraction of their lives under the influence of solar particles and radiation, and are subject to planetary perturbations. On the other hand, Kohoutek in its present tour of near-solar space should develop a great coma and tails, thanks to the large mount of matter that will be liberated from the frozen nucleus. Often, the discovery of a major comet comes only a few months before it reaches perihelion, (the closest approach to the Sun) but Kohoutek was found almost i0 months in advance. This early warning permits systematic planning and adequate preparation for a wide variety of coordinated experiments.

-more-

-17-

On the other hand, the time involved is far too short to permit development of new Spacecraft. Thus the response to the challenge of Kohoutek must make use of existing systems, or ones already well on the way to completion when Kohoutek was found. These are listed in Table i. Prime among them is Skylab. Skylab is unique among the spacecraft Kohoutek, thanks to its capabilities for long-tei_viewing near-perihelion astronaut payload viewing that will observe

response optimization.

The array of astronomical and solar experiments on Skylab (Table 2) will permit the flight crew to monitor Kohoutek in the UV and visible light ranges regardless of its angular separation from the Sun. This is a critical consideration, because Kohoutek's Sun angle will not exceed 45 until January 18th. The unmanned spacecraft are generally constrained to observing at either very large or very small sun angles. Table 3 indicates the tentative schedule for Kohoutek observations. This is subject to significant up-dating as the individual project offices and experimenters complete and refine their operational plans. Of particular importance are the ATM instrumen%s on Skylab. They can observe Kohoutek at perihelion when the comet is brightest and receives the most solar energy. At that time, ground-based observations are of very limited scope, due to scattered sunlight in the atmosphere. White light imagery (S052 experiment) will be performed on ATM at frame rates up to four per minute, much faster than possible with OSO-7, and with higher spatial resolution. Simultaneous mapping of the coma in four UV wavelengths can be accomplished (SO55), and high dispersion spectroscopy (SO82) may detect the existence of helium and deuterium for the first time in a comet.

-more-

 -18-

The ATM X-ray experiments are not listed in Table 2, the prospects for detectable cometary radiation in this wavelength range seam poor. However, a major solar flare could induce fluorescence in Kohoutek, leading to a positive result with the S054 instrument.

since

For a few days just before and just after perihelion, the ATM capabilities will be somewhat reduced due to the larger Sun angles of the comet. During these intervals, however, Kohoutek is too close to the Sun to be observed through the workshop's anti-solar airlock. These are the times for the astronauts to conduct EVA operations. The instruments operated during EVA would be the T025 coronagraph and the new S201B far ultraviolet camera. The TO25 observation requires pointing the instrument fairlyaccurately toward the Sun. For the S201B photography, the Skylab must be maneuvered so that the camera is shadowed by the ATM solar array. At the airlock, the instruments, including S201B, will operate well before and well after perihelion. An articulating mirror system will be mounted on the airlock and a roll of the spacecraft of up to 90 will be made. Implementation of about 24 of these rather major Skylab maneuvers during the mission are being considered. Ordinarily, no more than one would be performed per day. Comets are known for their unpredictability - for sudden flarings and shape changes. Such transient events are expected to occur in Kohoutek during the Skylab 4 mission and the astronaut crew will react by bringing appropriate instruments into play and increasing thecamera frame rates for brief intervals, or taking other special measures. Only on Skylab, among existing spacecraft, can mission planners change out or modify the instruments to take advantage of an unexpected phenomenon such as the appearance of Kohoutek. Although the stowage list for the Skylab 4 command module is still under review, officials expect to add a new instrument to the orbiting complement. This is the S201B far ultraviolet camera of Dr. T. L. Page and Dr. G. Carruthers (Naval Research Laboratory), which is

-more-

needed to photograph the hydrogen cloud that will surround the head of the comet. Filters to isolate cometary emissions, a UV-transmitting lens, and extra film to support the desired high frame rates near perihelion are among the other new items expected tO be sent up to Skylab. In addition to the ATM instru/nents, the following Skylab experiments will be used in the comet study: S019, Ultraviolet Stellar Astronomy; S063, Ultraviolet Airglow Camera; S183, Ultraviolet Panorama Camera; and T025, Multi-filter Coronagraph. The S019 instrument will obtain ultraviolet speotra that will be studied to determine the composition of the comet nucleus and the effects of the solar wind. The SO63 camera will obtain ultraviolet and visible color _otographs whiah can helpdetermine the distribution of selected constituents in _%e coma and tail. The $183 photometric data will help determine the distribution, lifetime and the effect of hydroxyl in the coma. The TO25 coronagraph's ultraviolet and visible light photographs should yield information on the particulate production and di_trlbution in the coma and tail.

-more-

-20Some Comet Kohoutek Facts is inclined at 14 to the Earth's orbit around the Sun). approach to the Sun (13 million miles), --

The ecliptic

orbit of Kohoutek (the plane of the

Perihelion--the comet's closest will occur Dec. 28 at 21 million km or 30 solar radii.

Naked-eye visibi!ity should begin in early November prior to sunrise. Eye-balling will switch to after sunset when the comet passes perihelion Dec. 28. Best viewing may come in evening twilight shortly after New Year's Day. Then full Moon will interfere until last third of January. At perihelion, tail will appear short because Earth view will be almost directly along its tail. Discoverer: Dr. Lubos Kohoutek; discovered graphically March 7, 1973 at Hamburg Observatory Germany with the 32-inch Schmidt telescope. photoin West

Bri@htness: Preliminary estimates of Kohoutek's brightness range from visual magnitude -2 to -i0. For comparison, the Moon's brightness is -12.7 Designation: Comets bear the names of their discoverers. This is Comet Kohoutek 1973f; the "f" denoting that this is the sixth comet discovered this year. The fifth was Comet Kohoutek 1973e, discovered about a week earlier by the same Dr. Kohoutek. Observation S_stems in Operation Kohoutek

Skylab Mariner Venus-Mercury Pioneer Spacecraft Copernicus (OAO-3) OSO-7 Sounding Rockets Airborne Infrared Observatory Far Infrared Balloon Program Ground-Based Observations

and

Lear-Jet

-more-

Skylab Name S052 White Light Description Coronagraph

Experiments

for

Kohoutek

Observations Operation ATM

Principal R.M. High

Investigator

MacQueen Altitude Observatory

S055

UV Spectroheliograph

E.M. Reeves Harvard College UV Spectrographs R. Tousey Naval Research

ATM Observatory ATM Laboratory EVA

S082

High

Resolution

T025

Multi-filter

Coronagraph

J.M. Greenberg Dudley Observatory K.G. Henize University of D.M. Naval Packer Research

S019

UV Objective

Prism

Spectrograph

Airlock Texas and NASA-JSC Airlock, Laboratory Airlock Windows

S063

UV Airglow

Camera

S183

UV Panorama

Camera

G. Courtes Space Astronomy Laboratory (Marseilles, France) Camera T.L. Naval Page Research

S201B

Far UV Electronographic

Airlock, Laboratory

EVA

ORBIT OF COMET KOHOUTEK (1973f), 1973-1974

CT 1

NOV 1, 11 FEB 1 _ECI 1 I, 197 2

1973 1 JAN 1 ,,i., SUN (MIN ) &

t,J I.-'

_,

1, 197_ 1 21 FB 1 1 I MAR 1

COMET KOHOUTEK(1973f)
MOTION NEAR PERIHELION AS SEEN FROM THE EARTH IN A SUN_ CEWrERED REFERENCE FRAME. THE TIME SCALE ON THE COMET TRACK IS SUBJECT TO UP-DATING WHEN AN IMPROVED ORBIT BECOMES AVAILABLE, HOWEVER. LOCATION AN0 ORIENTATION OF THE T1RAC_ WILL NOT CHANGE SIGNIFICANTLY.

"

ARC MIN.

.:'....:. ;..: "_""

**'Q'':"

70

60 504030 -

DEC.28

1973 DEC.27

-22-

Preliminary Pre-Perihelion Late

Phasing

of

Kohoutek

Operations

September/October

Resume

ground-based comet orbital

observations

- Recover November Improve

definition

- Launch MVM - Launch - Begin - Begin - Launch Skylab Lear-Jet Skylab far 4 flights airlock infrared observations balloon for airlock

December

Increased priority observations Comet tail B-stars - Possible passes

Scorpius

STP

72-1

observations

Near-Perihelion December 24 December 26-30

- Halt -

airlock ATM T025,

observations Observations $201B observations

Intensive for

- EVA - OSO-7

observations'

- High dispersion spectroscopy with ground-based solar telescopes Post-Perihelion January - Resume - Pioneer - Launch - Skylab Begin airlock observations

8 measurements sounding rockets

4 splashdown MVM observations

- Prime time for Copernicus observations and ground-based photography Begin C141 flights

-23-

Late

Post-Perihelion - Possible reflight infrared balloon of far

Spring

-more-

-24-

SKYLAB

3 ACCOMPLISHMENTS

(July

28

- Sept _ 25,

1973)

The second Skylab manned mission not only set a new manned space flight duration record of 59 days and ii hours but it also accomplished much more scientific experimentation than originally planned. In two of its main discipline areas--solar observation and Earth resources observationthe Skyla5 3 crew was successful in conducting half again as much observation as originally planned. Bean, Garriott and Lousma, observed the Sun through Apollo Telescope Mount instruments from above the Earth atmosphere 305 hours as compared with the pre-launch plan of 200 hours. Additionally the Sun cooperated with Skylab in presenting an unusual number of active solar events during what was expected to be a quiet period. In the Earth resources area, the conduct 39 passes over selected areas gather data in such areas as forestry, cartography, geology. Original plans 26 of these passes. Skylab 3 also exceeded pre-launch of biomedicine, technical and materials ments. crew was able to of the Earth to hydrology, oceanography, had been to conduct

plans in the areas processing experi-

During its 59 days and ll hours in space, Skylab 3 travelled more than 24 million miles. The mission brought the total United States man-hours in space to 17,831, about the equivalent of nine years work by a man working 40 hours a week. The crew, after an early experience with motion sickness, adapted well to the weightless environment and was eager for more work assignments as the mission progressed. In fact, during the last portion of the mission, the crew was able to do much more work per day than originally expected. From the 10th to the 15th day of the mission, the crew was able to devote about 19 man-hours a day to scientific experiments. From the 15th day to about the 20th day the rate increased from 27 to 33 man-hours per day in experiment work.

-more-

-25-

REAL-TIME ,, ,,. ,

,FLIGHT

PLANNING

Time

was

when

pre-mission

space

flight

plans

were

followed

"by the numbers" with few changes except those caused by systems malfunctions. Skylab flight planning, however, is almost done in real-time, with the pre-mission flight plan serving mainly as a guide to Mission Control Center flight planners. Each day's flight plan is designed to yield the highest experiment data return. Teleprintered to the Skylab the crew wakens, the dail_ space s_ation flight plan early takes in the morning advantage of

before

unique opportunities experiments. For ground observatory bearing upon when The Skylab (CST) with

that enhance data gathering for particular example, forcasts of cloud-free EREP sites and predictions of unusual solar activity have a EREP passes and ATM runs are scheduled. planning of flight cycle begins planners in at midnight Houston Mission Control Center

time

flight a team

drafting a "summary flight plan" for the followin 9 cr_w work day that will start 24 hours after the planning team ends its work shift. This first team is relieved by the so-called "execution, team (day team)of flight controllers concerned only with the existing detailed flight plan for the immediate day. The flight planners on the next, or "swing" shift develop from the summary flight plan a detailed flight plan for the following day, nailing down the activity details first summarized in the early morning hours --- and so on in leapfrog fashion. Daily flight plans pivot around experiment spacecraft systems status and optimum crew time sD/mnary flight plans embrace the viewpoints of engineers , experiment mlssion management, principal the flight requirements, usage. Propose4 Skylab systems

investigators, flight surgeons, crew and the weatherman's forecast Precedence is given to mandatory experiments, with other experiremaining time. will be reproduced JSC Newsroom. daily and

for potential EREP survey sites. operations, ATM, EREP and medical ments and operations filling the Revised distributed summary flight to newspersons plans at the

10

The normal p.m. CST

Skylab

crew

worhday

starts

at

6 a.m.

and

runs

until

Breakfast CST --- except who shifts his Eight hours of

is at 7 a.m., lunch at noon and dinne_ at 6 p.m. for the man on duty at the ATM console during lunch, meal time so that he can be relieved a_ the console. sleep are normally scheduled.

-- mor_

-26-

During the mission the astronauts will be operating and monitoring about 60 items Of experimental equipment and performing a wide variety of tasks associated with the several hundred Skylab scientific and technical investigations. Depending upon experiment scheduling requirements, Skylab crews have a day off about every seventh day. About two 15-minute personal hygiene periods are scheduied each day for each crewman and one hour and 30 minutes for physical exercise. Additionally, an hour a day may be set a_ide for R&R rest and relaxation. Mission Control Center flight planners fill hours of the crew work day with experiment the remaining operations.

eight

Some modifications to flight planning philosophy have been made as a result of experience in the two previous Skylab missions. A marked improvement in crew proficiency was noted after the second week of flight in both crews. Flight plan scheduling has been changed to take advantage of the time gained as crewmen adapt to space station operations. For example, meal periods have been shortened from one hour to 45 minutes, and the pre- and post-sleep periods have also been shortened. Housekeeping chores, such as trash disposal, filter changing and cleanup which was scheduled in the daily flight plan on the first two missions, will 5e on the daily "shopping list" for crew option to f_t into any slack time. These changes in flight planning methods have increased the normal experiment day from 22.5 to 28 manhours and are expected to yield more than 200 additional experiment manhouzs over a 56-day mission.

TYPICAL CREWDAY
GMTi 12 13 14 15 16 17 18 |9 20 21 22 23 24 I 2 3 I!

CDR

POST

AIM

_,T

PASSI

PT_I

ATM

_/_*1

PRE

SLEEP

CMN

SPT

SLEEP ACTIVITIES

S,4"IK

S B U

OBS ATM AT E C EREP

SUB SLEEP SLEEP ACTIVITIES

ERER P _A;'_J/ H M131-! PLT DAY/NIGHT

M131-1 M092/M171-1

II "iHII OBSEAT PASS-1SUB OBS I _ _ i ! IKll _ iI , i Jim '! ' _ j [

''

'

'"

_LEEP " "

,
|

POST SLEEPACTIVITIES

PRE-SLEEP ACTIVITIES

SYSTEM CONFIGURATION PH URINE SAMPLING T003 EXPERIMENT BODY MASS MEASUREMENT BREAKFAST DINNER PREP PRD READOUTS LOAD FILM REVIEW PADS STATUS REPORT

"S/HK

SYSTEM HOUSEI_EEPINGI

PH - PERSONAL HYGIENE PT - EXERCISE TVSU - TV SETUP * TIME AVAILABLE FOR COROLLARY EXPTS -

EVENING MEAL ATM (1 to 2 PASSES) MISSION PLANNING RECREATIONAL ACTIVITIES CONDENSATE DUMP TRASH AIRLOCK DUMP FOOD RESIDUEWEIGHING STATUS REPORT T003 EXPERIMENT SYSTEM CONFIGURATION FOR SLEEP PH BREAKFASTPREP

-28-

MISSION

PROFILE:

Launch , Dockin_

and

Deorbit

Skylab 4, the third manned visit to space station Skylab, will be launched at 11:41 a.m. EST November 10 from the NASA Kennedy Space Center's Launch Complex 39 Pad B, for a fifth-orbit rendezvous with the space station. The experimental station, designated Skylab i, was launched into an initial 431x432.9 km (233 by 234 nm) orbit inclined 50 degrees to the equator which is expected to be 427.3 by 432.9 km (231x234 nm) at Skylab 4 rendezvous. The standard five-step rendezvous maneuver sequence will be followed to bring the astronauts and the Command/Service Module into the space stationts orbit---two phasing maneuvers, a corrective combination maneuver, a coelliptic maneuver, terminal phase initiation and braking. The CSM will dock with Skylab's axial docking port at about eight hours after launch. After verifying that all docking latches are secured, the final Skylab crew w_ll begin activation of the space station but will sleep aboard the Command Module the first night. As in the frist two manned missions, timekeeping will be on a ground-elapsed-time (GET) basis until GET of eight hours, after which timing will switch over to day of year (DOY), or mission day (MD), and Greenwich Mean Time (GMT or "Zulu") within each day. Mission Day 1 will be the day the crew is launched. At the completion of the 56-day manned operations period, the crew will return to the CSM, undock and perform two deorbit burns---the first of which will lower CSM perigee to 168.3 km (91 nm) and the second burn will lower perigee to an atmospheric entry flight path. Splashdown will be in the north central Pacific 509 km (310 statute miles) north-northwest of Honolulu, Hawaii. Splashdown coordinates are 25o45'N x 159o15'W. Command Module touchdown, will he at 5:44 p.m. EST January 6, 1974. (Note: If the mission is extended after the press deadline, the JSC Skylab News Center will issue reentry landing timelines.) kit and

SL-4ENTRY ROUND G TRACEOR F ANSPSDEORBIT ANEUVER M

3O 2O -_

'10

_o--

'?

3O 40

60

?0 0 I0 20 30 40 50 60 70 80 90 tO0 IlO [20 i30 140 150 t60 170 180 170 160 150 140 [3,5 z2_ E W Longitude, deg

-30-

COUNTDOWN

After the July 28 launch of the second crew to man Skylab, the mobile launcher was brought back to the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. The stages of the next Saturn IB launch vehicle and a boilerplate Command/Service Module (CSM) were erected on the mobile launcher on July 31 and August i. Starting August 2, the impact of problems with two of the four control engine quadrants in the docked service module's attitude control system and the possibility of a rescue mission resulted in accelerated processing of the SL-4 launch vehicle and CSM for a possible rescue mission. Integrated testing of the launch vehicle stages was conducted while the CSM underwent thorough testing including simulated flights - in the altitude chamber of the Manned Spacecraft Operations Building at KSC. On August ii, the CSM was moved to the VAB and erected atop the Saturn IB. The vehicles were moved to Complex 39's Pad B on August 14 for pad integration and final tests. A Flight Readiness Test in preparation for the potential rescue mission was conducted September 4-5 and launch preparations went into a "hold" September ii at a point seven hours prior to the scheduled loading of hypergolic propellants for the Saturn IB's second stage auxiliary propulsion system and for the, CSM. The Skylab 3 mission ended successfully September 25 without the need for a rescue mission and the SL-4 space vehicle was returned to a routine flow on September 25 heading toward a planned launch date of November ii. As in the previous Skylab launch, SL-4 launch preparations differ from earlier ones in that the Countdown Demonstration Test (CDDT) and the final countdown have been incorporated into a single launch countdown. The early portion of the countdown will vehicle cryogenic fueling and final countdown without astronaut participation. include launch activities

Following the simulated T-0, the count will go into an operational hold until T-42 hours_ 30 minutes, prior to launch. The final recycled count will then proceed to launch. There will be no "dry" test with crew participation in the early portion of the count as was done on earlier missions.

-more-

-31-

Key events in the 30 minutes, include: T-36 hours

final

count,

beginning

at T-42

hours,

Begin 8 1/2-hour service module cryogenic fueling and pressurization. Start CSM mechanical buildup closeout_ to be oompleted at hours, 30 minutes. 30 minutes Install Launch Begin launch vehicle clearing RP-I and T-15

T-27hours

T-25 T-19 T-9 T-8 T-6

hours, hours hours hours hours,

vehiclebatteries. power pad transfer test.

area stage fuel)

Replenish 50 minutes

(first

Begin launch vehicle cryogenic propellant load. (Loading takes approximately 3 hours - replenish continues through remainder of coun__lo_m) Primary damper retracted crew enters on station

T-4 T-3 T-2 T-I

hours hours, hours, hour, 45 minutes 40 minutes 51 minutes

CSM

closeout crew

Flight

spacecraft Tests

Emergency Detection System (to T-I hour, 21minutes) LV power transfer test from

T-58 T-57 T-45 T-44 T-42

minutes minutes minutes minutes minutes

Clear Retract Launch

closeout Swing Escape

crew Arm

pad

area position

9 to park armed

System

Final launch vehicle range checks (to T-35 minutes)

safety

T-35

minutes

Last target update of the Launch Vehicle Digital Computer for Skylab rendezvous

-more-

-32-

T-15

minutes

Hold for liftoff adjustment maximum 3 minutes Swing 7 seconds Start Arm 9 fully retracted

T-5 T-3 T-50

minutes minutes, seconds

automatic

sequence transfer to

Launch Vehicle internal power Ignition Liftoff

T-3 T-0

seconds

sequence

starts

-more-

-33-

SKYLAB

RESCUE

VEHICLE

Preparations for placement of the Skylab Rescue Vehicle, CSM-II9, on Pad B at Launch Complex 39 will begin immediately after launch of SL-4. Based upon a November i0 launch, the mobile launcher will be returned to the VAB on November ii for refurbishment. The erection of the Saturn IB launch vehicle is scheduled for mid-November and the rescue spacecraft ~ which already has undergone altitude testing - is to be erected atop the two Saturn IB stages ana Instrument Unit at the end of November. The rescue CSM and its Saturn IB are scheduled for transfer from the VAB to the launch pad in early December for pad integration and final tests. Current scheduling calls for SL-R (the designation of the rescue mission) to be in a launch readiness configuration by the end of December. The countdowns for SL-4 and SL-R are identlcal from the T-minus 26 hour, 30 minute mark. The SL-4 launch countdown was restructured to match the rescue countdown. Following rescue countdown procedures during an actual launch will enhance confidence and provide a rehearsal for the KSC launch team in the event a rescue mission should become necessary. The Skylab Rescue Vehicle B until completion of the SL-4 will remain mission. on Complex 39's Pad

-end-

NASA/KSC

NOV73

_41