The idea of cameras in space to observe the earth’s climate was being developed as early as 1946. This was due to sparse data observation coverage and the expense of using cloud cameras on rockets. By 1958, the early prototypes for TIROS and Vanguard (developed by the Army Signal Corps) were created. As NASA‘s GOES-R satellite launch on Saturday marks a new era in weather observation from space, we take a stroll down the memory lane to trace the history of weather satellites.
The first weather satellite, Vanguard 2, was launched on February 17, 1959 as part of the space race between the United States and the Soviet Union. Vanguard 2 was designed to measure cloud cover distribution over the daylight portion of its orbit and to provide information on the density of the atmosphere for the 300-odd year lifetime of its orbit. For the planned 19 days of the experiment, the equipment functioned normally but the optical instrument’s data was poor because of an unsatisfactory orientation of the spin axis.
Television InfraRed Observational Satellite (TIROS)
Television InfraRed Observational Satellite or TIROS program proved the usefulness of satellite weather observation at a time when military reconnaissance satellites were secretly in development or use. TIROS-1 was launched on April 1, 1960 and is considered to be the first successful weather satellite in history. It is the first satellite capable of remote sensing of the earth, enabling scientists to view the Earth from a new perspective. NASA launched 10 TIROS satellites in total. By 1965, meteorologists combined 450 TIROS images into the first global view of the planet’s weather, picking up a line of clouds over the Pacific Ocean barreling toward the United States. TIROS paved the way for the Nimbus program.
The Nimbus series were seven satellites launched over a 14 years from 1964 to 1978 and revolutionized weather forecasting by providing some of the first consistent global measurements of the earth. Over 20 years since Nimbus-1 was launched, it was the primary research and development platform for satellite remote-sensing of the earth in the US. NASA transferred the technology tested and refined by the Nimbus missions to theNational Oceanic and Atmospheric Administration (NOAA) later. The technology and lessons learnt from the TIROS and Nimbus missions form the very basis of most earth-observing satellites NASA and NOAA have launched over the past three decades. The Nimbus series also ushered in the modern GPS era with operational search and rescue and data collection systems. The last in the series Nimbus 7 was launched on October 24, 1978 and its decay date was 1994.
Environmental Science Services Administration Satellite Program (ESSA)
The ESSA or Environmental Science Services Administration Satellite Program was initiated as an extension of the TIROS Program. ESSA-1 was launched on 3 February 1966 and operated normally until 6 October 1966 when its camera system failed. It was fully deactivated on 8 May 1967. For four years, ESSA satellites transmitted thousands of images back to earth, enabling ground stations to predict weather patterns, including hurricanes. Advances in technology allowed ESSA to more than double the amount of information gathered over the life of the program. When ESSA-6, was deactivated by NASA, its images were reaching more than 300 receiving stations around the world, in 45 countries. ESSA imagery was of a much wider scope, and better resolution, than the TIROS 9 program. ESSA design and missions were the result of a combined effort on the part of NASA, the Environmental Science Services Administration, the US Weather Bureau and the National Meteorological Center. Its success prompted further exploration of using space-borne weather prediction and monitoring devices, like ATS and the NIMBUS series. The last one in the series – ESA 9 – was launched on February 26, 1969 and was finally deactivated November 15, 1972 after an operational Period of 1,726 days. In 1970 ESSA was reorganized as NOAA.
Polar-orbiting operational environmental satellites
Polar-orbiting operational environmental satellites or POES stretch back to 1978 when the first modern weather satellite TIROS-N was launched. TIROS-N was operated for 868 days until deactivated by NOAA on February 27, 1981. Polar orbiting satellites such as QuikScat and TRMM began to relay wind information near the ocean’s surface starting in the late 1970s, with microwave imagery which resembled radar displays thus improving the diagnoses of cyclones and their locations during the 2000s and 2010s. Polar orbiting weather satellites circle the earth at a typical altitude of 850 km in a north to south (or vice versa) path, passing over the poles in their continuous flight, thus offering a much better resolution than their geostationary counterparts. At present, NOAA-17 and NOAA-18 function as primary spacecraft, NOAA-15 and NOAA-16 as secondary, with NOAA-14 in standby. The POES data support a broad range of environmental monitoring applications including weather analysis and forecasting, climate research and prediction, global sea surface temperature measurements, atmospheric soundings of temperature and humidity, ocean dynamics research, volcanic eruption monitoring, forest fire detection, global vegetation analysis, search and rescue, and many other applications.
Applications Technology Satellite (ATS)
The geostationary satellites followed beginning with the Applications Technology Satellite or ATS program in the late 1960s. The overall objective was to investigate and flight-test technological developments common to a number of satellite applications. The ATS series had a total of six satellites carrying out a variety of communications, meteorology, and scientific experiments, in addition to providing a platform for evaluating three different kinds of spacecraft stabilization systems. ATS-1 was launched on December 7, 1966. It carried a black-and-white weather camera which transmitted the first image of Earth and the moon together from a geosynchronous orbit, a feat often mistakenly attributed to Voyager 1. Voyager 1 captured the first single-frame image that showed the entire Earth and moon. ATS-1 was deactivated on December 1, 1978. Last in the series ATS-6 (Launched May 30, 1974). ATS-6, which was more sophisticated satellite than its predecessors, pioneered direct-broadcast TV. The vehicle also conducted air traffic control tests and practiced satellite-assisted search-and-rescue techniques. It carried an experimental radiometer that subsequently became a standard instrument aboard weather satellites.
Synchronous Meteorological Satellite (SMS)
The Synchronous Meteorological Satellite or SMS was a program where NASA developed two weather satellites – SMS-1 and SMS-2. SMS-1 was launched May 17, 1974 and SMS-2 was launched February 6, 1975. The prgram was a direct result of the successes achieved by the ATS program that demonstrated the feasibility of using satellites in geosynchronous orbit for meteorology.
Geostationary Operational Environmental Satellite (GOES)
The Geostationary Operational Environmental Satellite (GOES) series followed immediately after the SMS program in the 1970s. In fact SMS-3 went operational as GOES-1 on October 16, 1975. SMS-1, SMS-2 and GOES-1, GOES-2, and GOES-3 were essentially identical. The GOES is operated by the United States‘ National Environmental Satellite, Data, and Information Service (NESDIS) and is the foundation of weather monitoring and forecasting in the United States. Three GOES satellites are currently available for operational use — GOES-13, GOES-14, GOES-15. Several others in the series are still in orbit, either inactive or re-purposed. GOES satellites are placed in geostationary orbit above the equator at altitudes of 35,880 km. Because of this orbit, they remain stationary with respect to the rotating earth and thus can record or transmit images of the entire hemisphere below continuously with their visible-light and infrared sensors. The news media use the geostationary photos in their daily weather presentation as single images or made into movie loops.
Defense Meteorological Satellite Program (DMSP)
The Defense Meteorological Satellite Program or DMSP is an originally classified mission revealed in March 1973. It is managed by the Air Force Space Command with on-orbit operations provided by the NOAA. It monitors meteorological, oceanographic, and solar-terrestrial physics for the United States Department of Defense. They provide cloud cover imagery from polar orbits that are sun-synchronous at nominal altitude of 450 nautical miles (830 km). DMSP can detect the best of all-weather vehicles with its ability to detect objects almost as ‘small’ as a huge oil tanker. Among all the weather satellites in orbit, only DMSP can “see” at night in the visual because of its low moonlight sensor. Further, it can help monitor energy use and city growth. Not only do the satellites see the fires visually day and night, but the thermal and infrared scanners on board these weather satellites detect potential fire sources below the surface of the Earth where smoldering occurs.