1, 1960 -- TIROS I is Launched
The launch of TIROS I (Television and InfraRed
Observation Satellite) on April 1, 1960 marked the first
day it became possible to observe the Earth's weather conditions on
a regular basis, over most of the world from the vantage point of
The satellite designed to obtain
cloud pictures was rocketed into space aboard a Thor-Able launch vehicle,
in the early hours of April 1, 1960, from Cape Canaveral, Florida.
The satellite was basically a cylinder with 18 flattened sides to
mount solar power cells. The satellite was approximately 42 inches
(1.07m) in diameter, 22 inches (0.56m) high (including the projecting
television camera lense), and had a launch weight of approximately
283 pounds (128.4kg) including fuel for small solid rockets to control
the satellite's spin over time. For comparison, the latest generation
NOAA-15 satellite is 74 inches (1.88m) in diameter, and 165 inches
(4.2m) high in its "folded" launch configuration, and weighs
4,920 pounds (2231.7kg) at liftoff.
The main sensors that provided the
cloud pictures were television cameras. The TIROS cameras were slow-scan
devices that take snapshots of the scene below; one "snapshot"
was taken every ten seconds. These were rugged, lightweight devices
weighing only about 4.5 pounds (2 kg) including the camera lense.
TIROS I was equipped with two cameras. One had a wide angle lense
providing views that were approximately 750 miles (1207 km) on a side
(with the satellite looking straight down), and a narrow angle camera
with a view that was about 80 miles (129 km) on a side.
When the satellite was within range of a ground station, the
cameras could be commanded to take a picture every 10, or every
30 seconds. But each camera was also connected to a clock controlled
tape recorder to record images when the satellite was beyond the
range of a ground station. Each recorder contained 400 feet (122
m) of tape, and could record up to 32 pictures for playback the
next time the satellite was in range.
||There were two Command and
Data Acquisition (CDA) stations used for TIROS I. These were located
at the Army Signal Corps laboratory in Belmar, New Jersey and the
U.S. Air Force facility a Kaena Point, Hawaii. A third station, used
for engineering and back-up was located the the RCA plant where the
TIROS was built, in Hightstown, New Jersey.
When the satellite data was read
out at either of the CDA stations, it was recorded on 35-mm film for
making prints and large projections. From these, a hand-drawn cloud
analysis (nephanalysis) was made then transmitted by facsimile to
the U.S. Weather Bureau National Meteorological Center (NMC) near
Washington, D.C. It was not until 1962 (TIROS IV, TIROS V) that some
of the actual gridded satellite pictures were sent via facsimile to
NMC and some other large Weather Bureau offices
I ceased operating in mid-June 1960 due to an electrical failure.
During the 77 days it operated, the satellite sent back 19,389 usable
pictures that were used in weather operations. TIROS II was launched
on November 23, 1960.