Exploring the Unknown - NASA's History Office

ment, and sea ice monitoring, near-real-time data is even more critical, since the dynamic
phenomena themselves are short-lived and the period for action in response to observation
is also short. An early ERTS-B launch will provide assurance that the immediate
values in these application areas can be realized.
These two examples illustrate how the first phase of ERTS investigations has been
spent discovering and understanding the full extent of the informational content of space
data; the next phase now needs to focus on making information extraction routine and
on learning how the new information can be integrated into management and decision
processes. This next phase requires experimental support and continuity in the flow of
ERTS data. These are the considerations that led the Interagency Coordination
Committee for the Earth Resources Survey Program in its annual report to your office submitted
on October 4 to identify the acceleration of ERTS-B to 1974 as the best step in the
overall transition from R&D to operations.
A first-order analysis of the tradeoffs between the two launch dates shows the following:
• The earlier launch maintains the momentum developed in the investigator and
user communities, a momentum that would have to be reestablished at a cost in
money and performance if a serious gap in data flow were permitted.
[5] • The earlier launch is likely to provide earlier definitive experience among many
diverse users and applications upon which decisions as to operational systems timing,
configuration, and benefits can be reached.
• The earlier launch of ERTS-3 means that the fifth (10–14 micrometer) MSS channel
would not be carried until a later time; the development schedule for this
thermal IR channel would not be affected and the instrument could be flown in
1976 if a suitable spacecraft is available. A two-year discontinuity in ERTS data
availability is considered more serious than the potential delay in the flight test of
the additional experimental channel.
• The earlier launch date provides the possibility of near-continuous coverage following
ERTS-1 which has exceeded its design life and can be expected to fail at
any time. A later gap in data flow following ERTS-B in the period 1975–76 could
be filled with a follow-on experimental or operational system as I have already recommended;
however, this is a matter for a separate decision which can be made
on its merits in the FY 1975 budget process, independently of the decision on the
ERTS-B launch date.
• The earlier launch results in lower FY 1975 and total program costs.
I would like to reiterate a basic point: the objective of the ERTS program, to identify
whether an operational approach to ERS is warranted, is earliest and most economically
served by accelerating ERTS-B.
[6] Congressional Direction
EXPLORING THE UNKNOWN 279
The four Committees charged with the NASA authorization and appropriation have
clearly and unambiguously gone on record on the ERTS-B matter. The FY 1974 authorization
act includes $8 million specifically targeted for this purpose. Quotes are: “The
[House] Committee, however, places the highest priority on the ERTS project.” “. . . the
[House] Committee believes that ERTS-B should be prepared for launch as soon a practicable.”
“. . . the [Senate] Committee concurs with the House in adding $7 million to the
Space Applications Program to bring ERTS B into a ready status for launch in its present
configuration . . . .” “. . . the [House] Committee urges NASA to reprogram the necessary
funds to launch ERTS-B as early as possible.” [bracketed material in the original]
The basis for Congressional interest is not political in the usual sense. Data from
ERTS-1 is beginning to be used extensively by many different State agencies, and a serious