Trinity TestThe United States Army, and a retinue of scientists who have participated in the top-secret Manhattan Project to create a workable atomic bomb before the then-hostile governments of Germany or Japan can do so, carry out the first detonation of a nuclear weapon in human history, generating a massive explosion with a yield of 22 kilotons of TNT. This is the final test before the deployment of two nuclear weapons in the United States’ war with Japan mere weeks later. Manhattan Project scientists present to witness the test include Robert Oppenheimer, Richard Feynman, Enrico Fermi, and John von Neumann.

Operation Overcast

V2 RocketAfter Germany’s surrender, ending the European hostilities in World War II, American military forces embark on a program to recruit captured German scientists, particularly those involved in the development of rockets and missiles, to perform further research and development in these areas for the United States, especially with the Pacific war between the United States and Japan still very much an active concern. The German scientists are also interrogated to find out if any of their technology has been shared with Japan. Numerous German rocket scientists, notably Wernher von Braun and Eberhard Rees, are identified as possible assets to the American war effort despite their past affiliations with Germany’s Nazi regime.

The Upper Atmosphere Research Panel

V2 rocketThe first meeting of the Upper Atmosphere Research Panel, known more informally as the V2 Panel, is held, comprised of researchers from various universities, industry, and the military, to decide on peaceful uses for the nearly 80 rockets’ worth of German V2 rocket hardware seized in Germany at the end of World War II. The technology of the rockets themselves will be studied, while payloads are proposed to study the properties of Earth’s upper atmosphere, radiation received from the sun, and the environment of space itself. Also of key importance will be reverse-engineering the V2 to aid in the design of American-made sounding rockets. Eventually the German scientists and engineers who were taken into custody with the captured hardware will be brought to the U.S. to continue their research.

The Atomic Energy Act of 1946

AtomPresident Truman signs the Atomic Energy Act into law, laying the groundwork for both future military development of nuclear weapons and a civilian nuclear energy industry, though the latter will take time (and further amendments to the law) to develop. The primary development of the initial version of the law is the founding of the U.S. Atomic Energy Commission, a civilian agency intended to lead both areas of development (and intended to take over from the scientists who, up until now, had been operating in secret as part of the Manhattan Project). Over time, the Commission’s responsibilities will grow to include regulation, safety, and disposal of dangerous radioactive material. Major amendments will be made in 1954 under President Eisenhower to encourage the peacetime nuclear power industry to grow.

Operation Paperclip

Operation PaperclipPresident Truman, after months of weighing the pros and cons of offering amnesty to many of the German scientists involved in the V2 rocket program, signs off on Operation Paperclip, a project to repatriate those scientists to the United States. The initial estimate is that a thousand German scientists will be brought to the U.S., but over time the total will grow closer to 2,000, bringing well over 3,000 family members with them. Wernher von Braun and Hermann Oberth are among the scientists and engineers who accept the offer to work for the U.S., and their efforts, while they do have military value, will form the core of the nascent U.S. space program, with von Braun eventually designing the Saturn V rocket that will take future astronauts to the moon. The Soviet Union mounts a similar program in the weeks to come, attempting to repatriate German scientists and engineers to continue their rocketry research for the Soviets.


RDS-1The Soviet Union detonates its first nuclear weapon, internally code named RDS-1, near a specially-built “dummy” village which includes various structures, aircraft and other military hardware, and livestock, all present to test the effects of an atomic weapon detonation in their vicinity. Western intelligence is caught off guard when the radioactive fallout is picked up by detection equipment on weather reconnaissance flights between Japan and Alaska, as the Soviets were not expected to have their own nuclear weapons until sometime in the 1950s. This is a turning point in the Cold War, initiating the race toward the next evolution of nuclear weapons: the hydrogen, or thermonuclear, bomb.


AnankeUsing a telescope at Mount Wilson Observatory, astronomer Seth Nicholson discovers Ananke, a tiny moon of Jupiter orbiting the huge planet at an average distance of 21 million miles and at a high inclination relative to Jupiter’s equator. Ananke is most likely a captured asteroid or the remnant of a captured asteroid, and other small Jovian moons in the same orbit may be other pieces of the captured (and shredded) body. Ananke is the first Jovian moon discovered in nearly two decades, and it will be over two more decades before another is found.

Weather Radio: all weather, all the time

Weather RadioThe U.S. Weather bureau signs on radio station KWO35, located at New York’s La Guardia Airport, broadcasting weather forecasts primarily for the benefit of pilots. Not targeted for public consumption, the experimental station broadcasts for several hours a day at a frequency of 162.55Mhz, outside of the spectrum reserved for FM radio. A similar station on the same frequency will later sign on at Chicago’s O’Hare Airport in 1953, again mainly for the consumption of airline pilots. Marine forecasts are added later, and the system helps the Weather Bureau prevent its local forecasters from being overwhelmed by requests for “personalized” weather reports for pilots. These two stations are the precursor for the nationwide weather radio network operated by the Weather Bureau’s successor agency, the National Weather Service.

Weather Bulletin!

Weather BulletinThe U.S. Weather Bureau (forerunner of the National Weather Service) inaugurates the Severe Weather Unit at the WBAN (Weather Bureau-Army-Navy) Analysis Center in Washington D.C. Armed with recent research and decades of past research into the formation and behavior of severe thunderstorms and tornadoes, this is the first attempt to offer the military’s growing severe weather prediction capability to the American public. In these early days, before the adoption of specific types of weather watches, the WBAN Severe Weather Unit issues weather bulletins for tornadoes and severe thunderstorms alike; by early 1953, the Severe Weather Unit also issues “outlooks” with more general predictions about the probability of severe storms.

Baptism by fire…and wind

Weather BulletinThe newly formed Weather Bureau-Army-Navy Severe Weather Unit hits the ground running with its first tornado bulletin issued to the general public for portions of Texas, Oklahoma, Arkansas and Louisiana. This forerunner of the modern tornado watch is a misfire, however: the only two confirmed tornadoes occur, both outside the area covered in the bulletin. Critics within the Weather Bureau express doubt that such bulletins will ever be of use to the public, and may instead spark panic among the public; this attitude will all but disappear within three years.

Tornado Bulletin #2

Weather BulletinThe newly formed Weather Bureau-Army-Navy Severe Weather Unit‘s second attempt to warn the public that tornado formation is possible within a specific area strikes paydirt. Again covering a large area including portions of Texas, Oklahoma, Arkansas, and Louisiana, later expanded to include states east of this area, this forerunner of modern tornado watches is right on the money, predicting an outbreak of more than 20 tornadoes in Arkansas, Missouri, Mississippi and Kentucky. Despite the advance notification, the Severe Weather Unit has work to do in educating the public about its bulletins: over 200 deaths still occur as a result of the tornadoes.

Operation Hurricane

Operation HurricaneOperation Hurricane, the first test detonation of a British-built atomic bomb, takes place aboard a Royal Navy frigate anchored near the Monte Bello Islands off of the western Australian coast. The detonation has a yield of 25 kilotons, and is remotely detonated aboard the frigate to gauge the damage that would result from a scenario in which a nuclear device is smuggled into a sea port aboard a ship. This is a continuation of Britain’s own nuclear weapon development program initiated during World War II, and makes the U.K. the third nuclear-armed nation on Earth.

Ivy Mike

Ivy MikeThe United States conducts the first-ever successful test of a thermonuclear bomb at Enewetak Atoll in the Pacific Ocean as part of Operation Ivy. The explosion resulting from the first hydrogen bomb test has a yield equivalent to 10 megatons of TNT, with a three-mile blast radius, stripping vegetation from the ground in the surrounding area. There is significant radiological fallout from the event, and one pilot assigned to fly a jet fighter through the area an hour after the detonation loses control of his plane, crashes, and dies due to residual radiation interfering with his instruments and controls. Traces of the previously undiscovered (but theorized) elements einsteinium and fermium are found afterward.

Hook echo: first tornado detected by radar

Weather BulletinUsing a World War II-era aviation radar system, Illinois State Water Survey electrical engineer Donald Staggs makes the first radar-based detection of a nearby tornado, part of a tornado outbreak striking in and near Champaign, Illinois. The “hook echo” is the distinctive radar signature of a rapidly evolving small-scale cyclone developing from the larger radar signature of its parent thunderstorm. Continued observations confirm that this is the “radar shape” of a forming tornado, an invaluable piece of information for forecasters on the forefront of severe weather prediction.


RDS-6sThe Soviet Union detonates its first hydrogen bomb, code named RDS-6s, in its first thermonuclear weapons demonstration. The bomb is estimated to have a yield of 400 kilotons, thanks to a layered design devised by nuclear physicist (and later political exile) Andrei Sakharov, though Sakharov’s design is incapable of being scaled up, ending its use in later Soviet nuclear weapon designs.

Castle Bravo

Castle BravoThe United States’ thermonuclear testing program Operation Castle commences with the first detonation, code named Castle Bravo, on a reef near Bikini Atoll. The most powerful hydrogen bomb detonation carried out by the American military during the 20th century, Castle Bravo has a yield of 15 megatons, three times greater than predicted, with a blast radius of over four miles. Radioactive fallout spreads over 7,000 square miles of the Pacific Ocean, including neighboring islands and a Japanese fishing boat, with both populations showing symptoms of radiation sickness shortly afterward, forcing evacuations and later reparations.

The Severe Local Storms Warning Service

Weather BulletinFormerly the Weather Bureau-Army-Navy Severe Weather Unit, the recently-renamed Severe Local Storms Warning Service (SELS) relocates from Washington D.C. to Kansas City, Missouri. The new location puts the SELS closer to the American midwest, a hotbed of severe weather during the spring months, as well as placing it in close proximity to a major telecommunications hub (at this point, the SELS is reliant almost entirely on teletype transmissions). Additionally, precise definitions of what constitutes a severe thunderstorm (winds in excess of 50mph, wind gusts in excess of 75mph, and hail in excess of an inch in diameter) are established, as well as a concerted effort to target its weather bulletins to more precise geographic regions.

Did an asteroid kill the dinosaurs?

BOOOOOOOOOMM. W. De Laubenfels of Oregon State College submits an article to the Journal of Paleontology, proposing the idea that an asteroid collision with Earth caused the extinction of the dinosaurs. Citing the widespread damage caused by a comet or meteor’s explosion over the ground in 1908 in Tunguska, Siberia, Laubenfels postulates that an actual impact could have displaced enough material to block the sun, wiping out vegetation and smaller animals alike, choking off the dinosaurs’ food supply as well as dropping surface temperatures below survivable levels. At the time of publication, the possibility of an asteroidal collision with Earth is not thought to be a particularly major threat.

Nuclear Pulse Propulsion

Project OrionAs part of a post-Manhattan-Project program of seeking peaceful uses for the technology previously developed for the construction and delivery of nuclear weapons, an informal report authored in August by C.J. Everett and Stanislaw Ulam is distributed from Los Alamos National Laboratory to the Atomic Energy Commission and other interested parties on this date. The report outlines a theoretical space propulsion system which would eject and detonate a series of nuclear explosives behind a spacecraft, pushing it forward at high velocity. The suggested spacecraft design would carry a pusher plate and shock-absorber system to minimize the acceleration effects on crew members in a shielded payload section. This is the culmination of a series of ideas Ulam had devised over the past decade, which would theoretically put interplanetary or even interstellar travel within reach. As the space race heats up, Ulam and Everett’s proposal will be revisited and expanded upon, at least on paper; physicist Freeman Dyson, in particular, will spend considerable time and research on what will come to be known as Project Orion (unrelated to the 21st century Orion crewed spacecraft design).

The first hard disk drive

IBM RAMACIBM announces the IBM 305 RAMAC (Random Access Memory Accounting) mainframe, a computer as large as two refrigerators, containing the new 350 Disk Storage Unit, the world’s first hard disk drive. The nearly-six-foot-high drive consists of a huge metal case surrounding a towering stack of 50 double-sided magnetic platters, adding up to a total capacity of four megabytes. In 1958, IBM will introduce the option to double capacity by adding a second stack of drive platters to the casing. The 305 RAMAC and 350 Disk Storage Unit together weigh over a ton, and are leased to IBM’s clients for $3,200 per month.


Space AgeUnder the direction of President Eisenhower, the U.S. Department of Defense establishes a high-tech think tank, the Advanced Research Projects Agency (ARPA), to conduct scientific and technological research with both national security implications and purely for technological advancement. The formation of ARPA is a direct response to the Soviet launch of the Sputnik satellite, and in the years ahead ARPA will lay the cornerstone of what will later become known as the Internet, as well as making significant strides in space science, though the space-related part of ARPA’s initial charter will later be transferred to a new agency called NASA. As the Cold War heats up, ARPA will be renamed DARPA (Defense Advanced Research Projects Agency) and its slate of R&D projects will become almost entirely military-oriented.

Doppler weather radar

Doppler RadarThe U.S. Weather Bureau uses a mobile Doppler radar transmitting and receiving in the 3cm bandwidth to measure wind speeds in a tornado striking El Dorado, Kansas, which kills 13 people living in that city. With Doppler radar’s ability to detect and measure the velocity of wind and rain moving toward and away from the radar itself, it is ideally suited for tornado observations and detection. This mobile radar is later given to the Bureau’s National Severe Storms Laboratory in the 1960s, and is the beginning of a lengthy research program that culminates in the nationwide rollout of Doppler-based NEXRAD (Next Generation Radar) in the 1990s.

The integrated circuit

Jack KilbyImplementing a revolutionary new take on an idea that has existed on paper since the 1940s, recently-hired Texas Instruments engineer Jack Kilby demonstrates the first fully-functional integrated circuit, with all of the electronic components encased in germanium. While the U.S. Air Force immediately places an order for TI’s new integrated circuits, other engineers continue to refine Kilby’s invention, with Fairchild Semiconductor producing ICs encased in silicon. The move to silicon for ICs leads to smaller electronic devices and the development of microcomputer technology.

The Thousand Foot Radio Telescope

AreciboAfter months of lobbying the U.S. Air Force and the Advanced Research Projects Agency (ARPA) for help in funding a large-aperture radar/radio telescope dish for studies of Earth’s ionosphere and the space that lies beyond, Cornell University’s Bill Gordon publishes a report in the journal of the School of Electrical Engineering. Gordon’s report, setting out the basic parameters for the project, includes a reflector dish diameter of one thousand feet – a daunting prospect from a structural engineering perspective. Sites in Texas and upstate New York are considered before a natural limestone “bowl” south of the city of Arecibo, Puerto Rico emerges as a promising candidate site.

Project SCORE: first communication satellite

SCOREWith engineers and ground controllers working under absolute secrecy, the U.S. Advanced Research Projects Agency launches the Atlas rocket-based SCORE satellite, an experimental communications satellite capable of recording four-minute audio messages from the ground for later playback to another part of the world. Though the first communication transmitted to Earth by SCORE is a message from President Eisenhower wishing listeners a peaceful Christmas, there’s little doubt that it’s a thinly-veiled military hardware demonstration. SCORE remains in orbit for only a few weeks before burning up in Earth’s atmosphere.

Weather radar, pre-Doppler

WRS-57 consoleThe U.S. Weather Bureau installs the first WSR-57 weather radar in what in intended to eventually be a network of weather radars spanning the entire country. Derived from World War II radars, the WSR-57 is first installed at the National Hurricane Center in Miami, Florida, where it offers as much as two days’ advance notice of storms approaching the Florida coast in the years before weather satellites. This radar remains in service until 1992, when it is literally ripped off the NHC’s roof by the winds of Hurricane Andrew. It is later replaced by a WSR-88 NEXRAD radar, though by that time satellite imagery has become the primary means of remotely detecting major tropical weather events.

Fire the laser!

Ted MaimanAt the Hughes Research Laboratory in California, physicist Ted Maiman conducts the first completely successful laser demonstration, resulting in a brief pulse fired through a ruby. Though the concept of lasers had been published in the 1950s, Maiman is the first to develop a fully working test article. Within a few years, similar ruby lasers are used for numerous military applications, as well as early holography. Maiman’s test laser, when demonstrated again at a conference in 2010, is still operational.

Building Arecibo

AreciboProposed and designed by Cornell University, and funded by the Adavanced Research Projects Agency (ARPA), the Arecibo Ionospheric Research Center – a thousand-foot radar and radio telescope dish – begins construction in a natural limestone bowl south of Barrio Esparanza, Arecibo, Puerto Rico. Construction will take over three years, at a cost of nearly $10,000,000, with a steel feed receiver structure supported in mid-air over the parabolic dish by some five miles of steel cables. Facilities are constructed for scientists visiting the eventual facility, and additional facilities are constructed to shape aluminum into the mesh structure of the telescope dish on-site, a more economical approach than having those parts of the telescope shipped in from outside. Though conceived and pitched as a means of studying the ionosphere, with possible defense applications such as missile detection, the Arecibo facility will makes its best known contributions to astronomy after it opens.

Echo 1

ECHO!!!The experimental communications relay satellite Echo 1 is launched into orbit by NASA. A 100-foot metalized Mylar balloon, Echo 1 is a demonstration of passive signal relay, carrying no powered transmitters of its own; its reflective surface simply bounces signals back to Earth. Microwave signals, radio, telephone and TV signals are all successfully relayed via Echo 1; it remains in orbit for four months.

Courier 1B

Courier 1BThe U.S. Air Force launches the first active-relay communications satellite into orbit, Courier 1B (the original Courier 1 having been lost to a faulty launch vehicle earlier). Unlike the reflective Echo 1 satellite, Courier 1B uses power from the solar cells covering its spherical casing to reboost and retransmit the signals it receives from Earth. Once again, a message from President Eisenhower is transmitted, this time to be received by the United Nations. Clourier 1B remains functional for just over two weeks before a glitch renders it useless.

Sagan: let’s terraform Venus

Carl SaganIn the journal Science, Carl Sagan proposes an audacious scheme to alter the chemistry of the atmosphere of Venus, making it habitable for humans. His plan involves depositing algae colonies into the planet’s clouds to begin converting the planet’s carbon dioxide into breathable oxygen, and the idea is years ahead of its time (and will later prove to be impractical when more direct studies are made of the Venusian atmosphere).

Time to take longer strides

John F. KennedyAt a special joint session of Congress called to discuss “urgent national needs,” President John F. Kennedy sets a new goal for NASA (which has only just put a single American astronaut into space): “I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the earth. No single space project in this period will be more impressive to mankind, or more important for the long-range exploration of space, and none will be so difficult or expensive to accomplish.” Kennedy requests that Congress pass space-related budgets totaling half a billion dollars for 1962 alone (encompassing not only the Apollo program, but nuclear rocket development, weather satellite development, and communication satellites).

Gravitational assist

Mike MinovitchRecent Jet Propulsion Laboratory hire Michael Minovitch submits the first of a series of papers and technical memorandums on the possibility of using carefully-calculated gravitational assist maneuvers to speed transit time between celestial bodies while requiring minimal engine/fuel use. Where most previous scientific thought concentrated on using engine burns (and a lot of fuel) to cancel the effects of a planet’s gravity, Minovitch demonstrated that gravity could be a big help with a carefully calculated trajectory. Though nearly every planetary mission since then has capitalized on Minovitch’s research, it was initially rejected by JPL. Minovitch’s calculations are later revisited by Caltech grad student Gary Flandro, who flags down a particular combination of Minovitch’s pre-computed trajectories for a “grand tour” of the outer solar system, a mission which will eventually be known – in a somewhat scaled-down, less grand form – as Voyager.


TIROSNASA and the United States Weather Bureau launch the third experimental TIROS weather satellite, TIROS-3. Further refinements to the basic TIROS satellite system are made, but one of the satellite’s two television cameras fails within days of going into service. TIROS-3 proves the future life-saving potential of weather satellites by giving Earthbound meteorologists advance warning of the formation and strengthening of Hurricane Esther well before it makes landfall on the east coast of the United States. TIROS-3 is operational for less than a year.

AN602: Tsar Bomba

AN602The Soviet Union detonates the most powerful thermonuclear weapon built to date, code-named AN602, or, more informally, “Tsar Bomba”. Though it’s designed to deliver a yield of 100 megatons, the 27-ton device is only fueled enough to produce a 50-megaton explosion, still enough to be detected by other nations. (A U.S. reconnaissance aircraft is close enough to witness the detonation, so the test is hardly a secret to the western world.) The detonation registers on seismic sensors, and interferes with radio transmissions nearby for nearly an hour; the explosion is visible as far away as Norway and Alaska. Due to modifications made to avoid endangering the Soviet population, fallout is minimal, though that might not be the case were the weapon to be deployed offensively.


OSCAR-1 satelliteOSCAR-1, an experimental satellite designed and built by amateur radio engineers for a technology test, is launched as a secondary payload aboard an Air Force rocket whose primary payload is a reconnaissance satellite. This is the first launch in history with a secondary payload, and the first payload not developed by a specific government or its agencies. The amateur radio engineers of Project OSCAR built the simple transmitter satellite for a grand total of $35, with a finite battery life and no attitude control thrusters of any kind, to transmit the message “HI” in the 2-meter band until the battery expired (which happens a few weeks before the satellite re-enters Earth’s atmosphere in late January 1962). A nearly-identical OSCAR-2 satellite will be launched in June 1962, while OSCAR-3, launched in 1965, is capable of receiving and retransmitting signals.


TIROSNASA and the United States Weather Bureau launch the fourth experimental TIROS weather satellite, TIROS-4. Further refinements to the basic TIROS satellite system are made, and after TIROS-3’s discovery of a hurricane in the Atlantic well before it his the US, new enhancements are introduced specifically for early hurricane detection. TIROS-4 remains in orbit for less than six months.


TIROSNASA and the United States Weather Bureau launch the fifth experimental TIROS weather satellite, TIROS-5. Further refinements to the basic TIROS satellite system are made, including new systems designed to keep the satellite in orbit – and in service – for a much longer period of time. A problem with the Delta rocket used to launch TIROS-5 puts the satellite in an elliptical orbit which is maintained for less than six months.