Project Cyclops, A Design... - Department of Earth and Planetary ...

iO II
YEARS
4 5 7 I0 15 30
r 1 I F_ ]
from 10 GHz to 3 GHz might effect a factor of two
saving in cost.
At the top of Figure 7-3 is a time scale that assumes 3
years of preliminary planning and site development
followed by construction of antennas at the rate of 100
per year. At this rate of buildup, we see the cost of the
Cyclops project is on the order of $600 million per year,
on the
average.
IO IO
TOTAL
COST
A COMPARISON OF THE CYCLOPS AND OZMA
SYSTEMS
The only significant attempt ever made in this
country to detect interstellar signals of intelligent origin
was Project Ozma, mentioned in the last chapter. Table
7-1 compares the significant parameters of the Ozma
system with those of the proposed Cyclops bogey
system of 3.16 km clear aperture.
TABLE 7-1
I0 8
COHERENT SIGNAL DETECTOR
ENGINEERING
Parameter
S_S__mbol Ozma
Antenna diameter d 26m 3160 m
Antenna efficiency r/ 0.5 0.8
System noise temperature T 350°K 20°K
Resolved bandwidth Af 100 Hz 0. ! Hz
Integrating time r 1O0 sec 10 sec
Instantaneous bandwidth B 100 Hz 200 MHz
Taking the sensitivity to be proportional to (_d2/T)
i
RECEIVERS
IUNNELS
(r/Af) 1/2 we see that the sensitivity ratio of the Cyclops
to the Ozma System is
BUILDINGS
k
,
POWER
IMAGINC
IF DELAY
100) 1/2
Sc/° :\0--_'}\ 261 \201 \100 0.1
i
I
OPIICAL
SYSI[W
106_-__ 1 1 I 111J 1 1 1 I I £±±.J
102 iO 3 104
CLEAR APERTURE DIAMETER
Figure 7-3. Cyclops costs.
!
= 4X 106
Since the range limit for a given radiated signal varies
as the square root of the sensitivity and since the volume
that can be searched is proportional to the cube of
range, we see that the range and volume ratios of
Cyclops over Ozma are
Rc/o _ 2000
cost. Here is where creative innovation would really pay.
Unless the antenna costs can be greatly reduced, the
other costs of the system, while large in their own right,
are insignificant by comparison. Simply reducing the
maximum operating frequency of the antenna elements
VC/0 _ 8X 109
The target stars of Ozma, namely r-Ceti and e-Eridani,
are about l0 to 11 light-years from us. Any signal that
the Ozma system could have detected at this range could
74