Themisto
Astronomers catch fleeting glimpses of a new natural satellite of Jupiter, Themisto, though the initial estimates of its orbit are “off” enough that Themisto becomes “lost” and isn’t observed again until 2000. With a diameter of roughly five miles, Themisto marks the dividing line between the larger inner moons of Jupiter and the widely-scattered menagerie of asteroid-like outer moons orbiting the planet. Astronomers Elizabeth Roemer and Charles Kowal (who discovered another new Jovian moon in 1974) share credit for discovering the moon. Themisto is the last Jovian satellite to be discovered by ground-based telescope in the 20th century.
Nimbus 6
NASA launches the Nimbus 6 satellite, designed to observe weather patterns from orbit and test new weather and climate detection technologies. In addition to continuing the microwave and infrared observations carried out by Nimbus 5, Nimbus 6 studies the amount of solar radiation reaching or reflected by Earth, and sends real-time observations to the experimental ATS-6 satellite, allowing NASA to test techniques and technologies that will be used in the shuttle-era TDRS (Tracking & Data Relay Satellite) system.
SAS-C
NASA launches Explorer 53, renamed Small Astronomy Satellite C, from an Italian-owned offshore launch platform off the coast of Kenya. SAS-C is a smaller spacecraft than NASA’s larger Orbiting Astronomical Observatory (OAO) series, but can be aimed very precisely at any cosmic X-ray sources that it detects. One of SAS-C’s discoveries is MXB1730-33, a binary star giving off rapid X-ray bursts. SAS-C will remain in orbit and functional until it re-enters Earth’s atmosphere in 1979.
Landsat 2
NASA launches its second Landsat satellite, originally named ERTS-2 (Earth Resource Technology Satellite) and still based on the Nimbus experimental weather and Earth-observation satellites. Originally intended to be online for a year, Landsat 2 functions through 1982, carrying a suite of instruments and sensors nearly identical to that of Landsat 1.
From Weather Radio to Disaster Radio
After years of studies into the feasibility of constructing a nationwide disaster alert system, NOAA Weather Radio is officially designated the “sole government operated radio system” for both weather-related disasters and other major emergency announcements (nuclear attacks are specifically mentioned in the declaration from President Ford). This shift in policy toward using the National Weather Service’s radio infrastructure for all potential disaster situations is at least partially inspired by the April 1974 tornado “Super Outbreak” in the midwest. For the first time, Congress approves a budget earmarked specifically for weather radio, topping $3,000,000 for expansion in 1976.
You’re listening to Earth FM
The first transmission from Earth designed to be a message for interstellar listeners is broadcast from the newly-refurbished Arecibo Radio Telescope in Puerto Rico. Weighing in at 210 bytes, the message is a binary transmission that, when properly assembled, provides a graphical representation of Earth’s solar system, a human being, the makeup of human DNA and the elements from which it is constructed, and the population of Earth. Though the Arecibo dish is pointed in the direction of the M13 globular cluster at the time of the message’s transmission, that cluster will have moved in the 25,000 years it takes for the message to reach that location (and, in any case, Earth and its entire solar system will have moved in the 25,000 additional years it would take to receive a reply), so the message is more of an interstellar technology demo than a message in a bottle.
NOAA-4
NASA and the National Oceanic & Atmospheric Administration launch NOAA-4, a weather satellite intended to operate in a near-polar low Earth orbit. NOAA-4 is based on the already-flown ITOS satellite design, and will operate without any major malfunctions through November 1978.
Leda
Astronomer Charles Kowal discovers Leda, a tiny, previously undiscovered moon of Jupiter, using Mount Palomar Observatory’s telescope. With a radius of less than seven miles and an inclined orbit, Leda is the first Jovian moon discovered in over two decades, and is among the last to be discovered using ground-based telescopes in the 20th century.
NOAA-3
NASA and the National Oceanic & Atmospheric Administration launch NOAA-3, a weather satellite intended to operate in a near-polar low Earth orbit. NOAA-3 is based on the already-flown ITOS satellite design, and will wait in orbit until March 1974, when the failure of an instrument aboard its predecessor, NOAA-2, requires putting NOAA-3 on full weather-watching duty, where it will remain without any major malfunctions through August 1976.
WABOT-1
At Tokyo’s Waseda University, robotics pioneer Professor Ichiro Kato and his team unveil the first full-size humanoid robot, WABOT-1. Capable of hearing and responding in speech, grasping objects, using artificial eyes to measure distances to objects, and rudimentary walking movement, WABOT-1 is the culmination of designs laid out as early as 1967 and construction and testing begun in 1970. Its creators estimate that it had the mental abilities of an 18-month-old child. (It is still intact and on display at Waseda University.)
Chasing the storm
The National Severe Storms Laboratory in Norman, Oklahoma dispatches “storm chasers” to track, follow, and observe the behavior of storms in a predicted tornado outbreak. The chasers manage to document the complete development of a tornado in Union City, Oklahoma on film and on an experimental Doppler radar system; for the first time, large-scale cloud rotation at high altitude is observed on radar prior to the appearance of a funnel cloud, a key discovery in tornado prediction. This phenomenon, called the Tornadic Vortex Signature, is a precursor to virtually every radar-detected tornado.
Nimbus 5
NASA launches the Nimbus 5 satellite, designed to observe weather patterns from orbit and test new weather and climate detection technologies. Launched into a polar orbit from Vandenberg Air Force Base in California, Nimbus 5 includes newly-developed experiments to examine Earth in the microwave and infrared portions of the spectrum.
SAS-B
NASA launches Explorer 48, renamed Small Astronomy Satellite B, from an Italian-owned offshore launch platform off the coast of Kenya. SAS-B is a smaller spacecraft than NASA’s larger Orbiting Astronomical Observatory (OAO) series, but can be aimed very precisely at any gamma ray sources that it detects. One of those sources turns out to be the pulsar remnant of a massive supernova, a discovery later named Geminga. An electrical fault will end SAS-B’s functionality in June 1973, and it will re-enter Earth’s atmosphere in 1976.
NOAA-2
NASA and the National Oceanic & Atmospheric Administration launch NOAA-2, a weather satellite intended to operate in a near-polar low Earth orbit. NOAA-2 is based on the already-flown ITOS satellite design, and will function in orbit through October 1974, with a break of only a few months due to a failed vertical temperature profile radiometer instrument. NOAA-2 will be shut down in January 1975.
Orbiting Astronomical Observatory 3: Copernicus
NASA launches the third and final Orbiting Astronomical Observatory satellite, given the nickname “Copernicus” when it successfully enters service near the 500th anniversary of the birth of the famed astronomer of the same name. OAO-3 is a joint venture between NASA and universities in the U.S. and the U.K., again focusing largely on ultraviolet observation of the sky, and it is instrumental in the discovery and study of long-period pulsars. OAO-3 will remain in service through February 1981, its successful nine-year mission lending weight to the ongoing construction and planning of NASA’s Space Telescope project, later to be known as the Hubble Space Telescope.
A near miss: the Great 1972 Fireball
In the broad daylight of mid-afternoon, an asteroid measuring somewhere between 10 and 50 feet in diameter plows through Earth’s atmosphere over North America, creating a long-tailed fireball across the sky. Undetected before its close pass – only 35 miles from Earth’s surface – asteroid US19720810 skips off of the atmosphere and back into space, having lost half of its mass to the frictional heating of plummeting through the atmosphere. The spectacle lasts only a couple of minutes, and US19720810 will make another pass by the Earth in 1997 (though not at such a close distance).
Landsat 1
Originally named ERTS-1 (Earth Resource Technology Satellite), NASA’s Landsat satellite, based on the Nimbus weather satellites, is launched to begin constant observations of Earth’s land, air and oceans. Landsat 1’s tour of duty lasts just under six years, during which it discovers a previously unknown island – never before spotted from land or sea – off the northeastern Canadian coast. Landsat 1 remains in service through 1978.
Tornado Intercept Project
Students and seasoned weather researchers at the National Severe Storms Laboratory in Norman, Oklahoma embark on the Tornado Intercept Project (TIP), a concerted effort to gather film footage of developing or active tornadoes in an effort to study wind and debris patterns. Though believed by some to be of limited scientific value, TIP is the beginning of “storm chasing” and yields major breakthroughs in scientific understanding of the formation of tornadoes just one year later.
The Fujita Scale
Dr. Tetsuya Theodore Fujita, a pioneering researcher in the formation and development of severe weather, proposes a scale for judging the intensity of tornadoes by the damage left behind. His five-point scale covers minimal tornadoes (F1) through storms capable of inflicting incredible damage (F5), with damage surveyed after a storm to determine the physical effects and the estimated wind speed needed to cause those effects. The Fujita Scale is adopted almost worldwide, remaining in widespread use by severe weather researchers and government agencies until it is supplanted by the more refined Enhanced Fujita Scale in the 1990s.
The voice of the National Weather Service
The National Weather Service’s NOAA Weather Radio system finally finds its purpose with the introduction of a piercing “warning tone” preceding emergency weather announcements such as severe weather warnings. Manufacturers of weather radio receivers (an item which hit the market in 1970) use the five-second burst of 1050Hz warning tone to trigger attention-grabbing alert sounds and then activate the radio so the relevant information can be heard. NOAA Weather Radio broadcasts on 29 stations around the country, and the agency continues to bring new transmitters online throughout the year.
The dawn of Doppler radar
The National Severe Storms Laboratory‘s 10cm Doppler weather radar begins full-time experimental operation in Norman, Oklahoma, just in time for the region’s active severe weather season. A surplus Air Force radar left over from the Distant Early Warning radar network (also known as the DEW Line) is installed and housed in a facility that’s also made of military surplus parts. There is no real-time display at first: researchers and meteorologists store the Doppler radar’s observations on computer tape that has to be processed and printed months after the fact, and compared to archived records from the existing WSR-57 radar at Norman.
NOAA-1
NASA and the newly-rechristened National Oceanic & Atmospheric Administration (formerly ESSA) launch NOAA-1, a weather satellite intended to operate in a near-polar low Earth orbit. Equipped with four cameras, NOAA-1 will operate in orbit for nearly a year before it begins suffering equipment malfunctions. Overheating in the spacecraft’s attitude control system forces ground controllers to turn off some of its weather sensing equipment, and NOAA-1 will eventually be shut down in August 1971.
NOAA
The United States government reorganizes ESSA (the Environment Science Services Administration) into NOAA or the National Oceanic & Atmospheric Administration, an agency responsible for weather prediction and research and for functions involving oceanic conditions, coastal fisheries, and then-current investigations of a potential Alaskan oil pipeline.
Nimbus 4
NASA launches the Nimbus 4 satellite, designed to observe weather patterns from orbit and test new weather and climate detection technologies. Nimbus 4 is among the first satellites to test what will become known as global positioning system technology, capable of pinpointing ground-based targets with special equipment. The satellite begins to experience intermittent attitude control problems in 1971, but remains in at least partial service through 1980.
TIROS-M / ITOS
NASA and ESSA launch the ITOS satellite, also known as TIROS-M, a next-generation weather satellite intended to take over from the constellation of short-lived ESSA weather satellites. With a configuration that is, for the first time, significantly different from the TIROS/ESSA satellites, the TIROS-M design’s shakedown cruise is a short and bumpy one: after system failures force a shutdown of the satellite’s attitude control system, it is shut down in mid-1971.
Nimbus 3
NASA launches the Nimbus 3 satellite, designed to observe weather patterns from orbit and test new weather and climate detection technologies. Nimbus 3 is the first Earth-orbiting spacecraft to test the SNAP-19 radioisotope thermoelectric generator system; devices similar to the SNAP-19 will become the primary power source for later deep space and outer solar system interplanetary missions. Nimbus 3 loses attitude control in 1970, but is kept online for engineering information-gathering purposes until 1972.
ESSA-9
The recently-rechristened Environmental Sciences Service Administration launches, with the help of NASA, ESSA-9, the latest in a constellation of weather satellites. ESSA-9 is the last weather satellite to carry the ESSA designation, as the government reorganizes ESSA into a new agency, NOAA, the following year. ESSA-9 remains in service until 1972.
ESSA-8
The recently-rechristened Environmental Sciences Service Administration launches, with the help of NASA, ESSA-8, the latest in a constellation of weather satellites operated by the former U.S. Weather Bureau. ESSA-8 is the first satellite in the ESSA constellation to boast a significant operational life span, watching Earth’s cloud patterns until it is shut down in 1976.
Orbiting Astronomical Observatory 2: The Stargazer
NASA launches the second Orbiting Astronomical Observatory satellite, given the nickname “Stargazer” after it successfully enters service. OAO-2 will remain in service for over four years, making significant contributions to the scientific understanding of comets and supernovae. Two separate experiments, including one designed and overseen by Dr. Fred Whipple, observe the sky in ultraviolet light from Earth orbit.
Arecibo and the Crab Nebula Pulsar
Cornell University student Richard Lovelace, working at the Cornell-funded Arecibo Radio Telescope in Puerto Rico, uses the massive telescope and its on-site computers to determine the rotational period of a pulsar discovered near the center of the Crab Nebula, approximately 6,500 light years from Earth. The position of the pulsar relative to the nebula strengthens the case for pulsars and (still hypothetical) neutron stars occurring at the heart of supernova remnants. The Crab Nebula pulsar had been discovered only three years earlier.