2018-10-30 13:02:05.0 [sritz]
insert Definition (id: null
text: The ESSA-4 satellite replaced ESSA-2 and provided direct readout cloud-cover photography to ground stations worldwide using APT. The spacecraft was an 18-sided polygon, 42 inches in diameter, 22 inches high and weighed 290 pounds; it was made of aluminum alloy and stainless steel, then covered with 9100 solar cells. The solar cells served to charge the 63 nickel-cadmium batteries.
The two cameras were mounted 180-degrees opposite each other along the side of the cylindrical craft. The "cartwheel" configuration of the TIROS-9 was selected as the orbital configuration of the ESSA satellites. Therefore, a camera could be pointed at some point on Earth every time the satellite rotated along its axis. The spacecraft operating system was the same as on the TIROS-9. The craft was placed in its planned Sun-synchronous 101-degree inclination retrograde orbit. The APT system was designed to transmit an image every 352 seconds, each photo covering a 2000-square mile area with 2-mile resolution. ESSA-4 was able to transmit two to three images daily to individual ground stations regardless of their location.
ESSA-4 Stats:
Launch Date: January 26, 1967
Operational Period: 465 days until deactivated by NASA on May 5, 1968
Launch Vehicle: Thrust Augmented Three-Stage Delta
Launch Site: Vandenberg Air Force Base, CA
Type: Weather Satellite
language code: en);
The ESSA-4 satellite replaced ESSA-2 and provided direct readout cloud-cover photography to ground stations worldwide using APT. The spacecraft was an 18-sided polygon, 42 inches in diameter, 22 inches high and weighed 290 pounds; it was made of aluminum alloy and stainless steel, then covered with 9100 solar cells. The solar cells served to charge the 63 nickel-cadmium batteries.
The two cameras were mounted 180-degrees opposite each other along the side of the cylindrical craft. The "cartwheel" configuration of the TIROS-9 was selected as the orbital configuration of the ESSA satellites. Therefore, a camera could be pointed at some point on Earth every time the satellite rotated along its axis. The spacecraft operating system was the same as on the TIROS-9. The craft was placed in its planned Sun-synchronous 101-degree inclination retrograde orbit. The APT system was designed to transmit an image every 352 seconds, each photo covering a 2000-square mile area with 2-mile resolution. ESSA-4 was able to transmit two to three images daily to individual ground stations regardless of their location.
ESSA-4 Stats:
Launch Date: January 26, 1967
Operational Period: 465 days until deactivated by NASA on May 5, 1968
Launch Vehicle: Thrust Augmented Three-Stage Delta
Launch Site: Vandenberg Air Force Base, CA
Type: Weather Satellite (en)