Hatsunese Space Program - HASDA (Japan-like) | 1989-03-12 | Saki-09, first Phobos/Deimos landings

Phase 1 - 01 - Introduction, Negi-1 sounding rocket (1952)
In a parallel universe, the country of Hatsunia (初音国) had taken a very different path compared to Japan, a similar country in our universe. Instead of hundreds of years of feudal isolation, the society became used to foreign contact and social reform. Unlike Japan, its international relations in the late 19th and early 20th centuries mostly involved diplomacy and trade with its neighbors instead of brutal militaristic conquest. During the Second World War, Hatsunia joined the Allied Powers and formed the Honolulu Pact with the United States in 1941 against a China that had been taken over by fascists in this timeline. The Allies achieved victory several years later, and with Hatsunia not being on the defeated side, its aerospace industry would not be obstructed by treaties, constitutional articles, or ruined infrastructure. At the beginning of the space age, Hatsunia did not have the native resources to directly compete with the Soviet Union or United States in spaceflight achievements, but had just enough to invest in small rockets and the cultivation of electronics and computing industries. As time went on, Hatsunia's economy would take advantage of post-war international trade networks and the digital revolution, and its space industry would eventually become the forefront of capability and affordability in the 21st century.

For more information about Hatsunia, visit this page and the wiki. This is a pseudo-alternate history in a parallel universe that wasn't meant to be fully realistic. Like Japan, Hatsunia isn't only about anime.

If you're wondering, "why a space program inspired by Hatsune Miku?" please read this. (not everything will be Miku-related)

The Hatsunia Aerospace Science and Development Agency (初音国宇宙航空科学開発機関) was established in 1958.

[Japan used to have three aerospace agencies: ISAS (scientific space probes), NASDA (practical satellites/human spaceflight), and NAL (mostly aeronautics). They were merged to become JAXA in 2003. In Hatsunia, their responsbilities were merged since the beginning.]


This is an alternate history-like self-roleplay which will will be depicted in Kerbal Space Program with modified versions of the Real Solar System and Realism Overhaul mods (and Zorg's TUFX shader configs). The Realistic Progression 1 (RP-1) career mode mod is also used to give structure to the missions, but it will not be a legitimate playthrough as progression through the tech tree is dependent on gathering science points from the moon and other planets as soon as possible. Thus, technologies will be manually unlocked at a pace according to their respective times. The TestFlight (engine failure) mod will also not be used. Custom contracts will also be made. Think of it as part career, part sandbox.

(Click "Index" on the top right corner of this post to see the list of chapters)

(Video playlist)



Phase 1 - 01

In Minamikushi Prefecture, the Hatsunia Science and Technology Agency constructed a facility on the island of Negishima, named after the green onion that the island was coincidentally shaped like (and was on the Hatsunese flag). Parts of the agency focused on the development of rocketry for scientific purposes, while the Hatsunia Defense Forces also saw its potential value for military applications. Professor Hidemi Utagawa of the University of Minamikushi led the development of Hatsunia's first sounding rocket.


This sounding rocket was the Negi-1, and was similar to the American WAC Corporal rocket. The vehicle was composed of two stages. The upper stage, or sustainer, was composed of steel and was powered by the LE-01 liquid rocket engine. It used a simple pressure-fed design and was fueled by a toxic mixture of aniline, furfuryl alcohol, and inhibited red fuming nitric acid, which required careful handling but could be stored for long periods of time. The LE-01 was the first in a series of liquid rocket engines developed by Mikubishi Heavy Industries, which previously manufactured ships and aircraft. At the top of the stage was a nose cone and an additional cylindrical compartment carrying a payload of scientific measuring instruments, including a thermometer and barometer. Fins, twisted by a fraction of a degree, provided flight stability through rotation. The lower stage, or booster, resembled the American "Tiny Tim" rocket and was known as the "Pencil," containing solid nitroglycerin and nitrocellulose propellant. Its purpose was to provide a short burst of thrust and acceleration so that the second stage's fins could stabilize effectively.

The diagram below compares its size to a modern interpretation of Hatsune Miku, a mythical singer originating from ancient Hatsunese folklore.


On 1952 August 31, the first Negi-1 was on the launch pad after several weeks of construction. The launch platform was slightly tilted to the east so that the rocket would not crash into any populated areas.


(Captions provided by the Historian mod)

It lifted off at 01:39:39 UTC (11:39:39 local time), jettisoning the "Pencil" booster after one second.


In less than a minute, it was already in the stratosphere, and after two minutes, the Negi-1 became the first Hatsunese object to surpass 100 kilometers, the boundary of outer space known as the Kármán line.


At three minutes, it reached a peak altitude of 113 kilometers, collecting data on pressure and temperature in the tenuous upper atmosphere before falling back down and sinking into the Pacific Ocean at over seven minutes after launch.

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Phase 1 - 02 - Negi-1A sounding rocket (1954)
Phase 1 - 02

Analogous to the Aerobee rocket, the Negi-1A sounding rocket was only slightly wider and taller than its predecessor, but had almost three times the propellant volume. An upgraded liquid engine, the LE-01A, was developed by Mikubishi Heavy Industries, designed to work with the same fuel mixture but at slightly different ratios. The nozzle of the "Pencil" solid rocket motor was modified to produce extra thrust. Negi-1's propellant tanks were made from steel, with the tank and walls being separate structures. The Negi-1A used aluminum, a lighter material.


The first launch occurred on 1954 September 8. The modular payload containers could be stacked to provide extra capacity for instruments.


Surpassing 200 kilometers above the ocean, the rocket carried an ion mass spectrometer to determine the composition of the upper atmosphere by ionizing the atoms and passing them through electromagnetic fields to analyze the spectra they produce.


On 1954 December 8, the first recoverable payload was launched. It contained the standard equipment as well as the first animal: a hamster.


After separating the payload from the rest of the rocket, an altitude of 200 kilometers was also reached.


The payload fell back down at a rapid rate, slightly heating up as it slowed down. But instead of crashing, it deployed a small drogue parachute at a high altitude, and the main parachutes near sea level. Recovery teams were established downrange, ready to retrieve the splashed-down payload.

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Phase 1 - 03 - Negi-2 sounding rocket (1957)
Phase 1 - 03

The Negi-2 sounding rocket was developed to study Earth's ionosphere and thermosphere with larger payloads for the International Geophysical Year (IGY), an event lasting from July 1957 to December 1958. Being far from Europe, Hatsunia did not get as much access as the United States and Soviet Union (or the United Kingdom and France) to captured V-2 rocket technology, or German rocket engineers. However, through the Honolulu Pact of 1941 and other defense agreements with the US, Hatsunia was able to assist with and gain knowledge from the Viking and Vanguard rocket programs. But unlike Vanguard, this project would be less rushed for better reliability. Mikubishi developed a new engine, the LE-02 (similar to the XLR50/X-405 engine), which used liquid oxygen and a special form of kerosene known as Rocket Propellant 1 or RP-1. Unlike previous engines, which were pressure-fed, propellant would be actively fed into the engine using a more complex gas-powered turbopump. The aluminum tank structure included stringers for improved integrity.

As Hatsunia's first guided rocket, the military was also interested in it as a technological demonstrator for larger ballistic missiles [unthinkable for our timeline's Japan]. The advent of larger rockets brought concerns from local fishermen, who were worried that rocket launches would scare away the fish. The government negotiated with the fishermen, justifying being able to launch at any time of the year for national security in missile development, and providing monetary compensation just in case launches proved to disrupt catches.

[context: For decades, Japan's space program could only launch for 190 out of 365 days a year because of the fishing industry, and there was no data regarding disruption as of 1997. The restrictions were lifted in 2010, citing the need for an independent launch capability.]


The first launch of the Negi-2 was on 1957 July 1, the first day of the IGY. The LE-02 consisted of a gimbaled main engine for pitch and yaw control, flanked by two smaller vernier engines for roll control.


This was a test of the rocket's downrange capabilities, reaching Mach 10 before jettisoning its payload, which splashed down over 1000 kilometers away from the space center.


Three months later, and about a week after the Soviet Union launched the first-ever artificial satellite, another launch brought extra equipment including a camera to over 500 kilometers above Hatsunia's eastern islands.


All payloads were recovered by parachute.

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Phase 1 - 04 - Formation of HASDA, Negi-2A sounding rocket (1958-1959)
Phase 1 - 04

The launch of the first satellite by the Soviet Union, followed by the United States just a few months later, motivated the Hatsunese government to form a dedicated organization for space research and development.
On 1958 October 19, the Hatsunia Aerospace Science and Development Agency (初音国宇宙航空科学開発機関) was formed, coincidentally only a few weeks after NASA started operations. Plans were being made for Hatsunia's first satellite, which would be decided upon at the Scientific Satellite Symposium in June 1959, and launched near the end of 1960.


To prepare for orbital launches, the Negi-2A sounding rocket was developed. The kerolox LE-02 engine had its thrust uprated, and the first stage was stretched. The new second stage was powered by the Mikubishi LE-03 engine (similar to the AJ10 engine), an upgrade of the LE-01 using unsymmetrical dimethylhydrazine (UDMH) and inhibited white fuming nitric acid (IWFNA). This stage also used a new and more complex construction technique which integrated tank walls with the outer walls to save mass. It would also test small reaction control thrusters fueled by nitrous oxide to orient the stage in the vacuum of space.


On 1959 January 31, the first launch occurred with a minimal payload, to test the downrange performance capabilities of the vehicle.


(The Modular Launch Pads mod is great for immersion.)

Stage separation occurred at two minutes into the flight, traveling over Mach 5. The first air-started engines immediately fired after separation to settle the propellant at the rear of the tank and stabilize the vehicle using gimbaled thrust.


After the second stage depleted its fuel, the reaction control system was demonstrated in rotating the vehicle. This would be required on the actual orbital launch, for orientation, spin-stabilization, and propellant settling of a third stage, which would be powered by an LE-01A engine. The second stage surpassed a downrange distance of 3000 kilometers, losing contact with Hatsunese tracking stations as it passed over the horizon and burned up on re-entry.

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Phase 1 - 05 - Negi-2B rocket, first satellite (1960) [VIDEO]
Phase 1 - 05

The Negi-2B was Hatsunia's first orbital launch vehicle, adding an additional third stage to its predecessor, which used the same LE-01A engine as the Negi-1A sounding rocket. The third stage was housed within a fairing, with a conical shape for simpler production, to protect it from atmospheric pressure and heating during ascent. Hatsunia's first satellite was known as HATSUNE (High Altitude Test Satellite Utilization Near Earth), and would be 1.58 m and 42 kg when in orbit, as it included the 25-kg empty mass of the Negi-2B third stage plus a 17-kg payload. Its purpose was to test technologies and perform basic scientific experiments. The satellite contained transmitters, accelerometers, a thermometer, and a Geiger-Muller counter to detect cosmic rays.



Launch occurred on 1960 August 31 at 03:39:39 UTC (13:39:39 local time).


HATSUNE was placed in a slightly elliptical orbit with an apogee of 1724 km and a perigee of 392 km, thus Hatsunia became the third country to launch a satellite into orbit after the Soviet Union and United States. It further verified the existence of the Van Allen radiation belts which had been confirmed by the Explorer 1 spacecraft two years earlier. The satellite did not have any way of generating electricity and the spacecraft lost battery power after several days of operation and transmission.


Fairing separation three minutes after lift-off


After the first two stages boosted the payload out of the atmosphere, the second stage used its reaction control thrusters to spin-stabilize about thirty seconds before the release of the third stage, which quickly burned its propellant to accelerate to orbital velocity.

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Phase 1 - 06 - Negi-2B, more early satellites (1960-1961)
Phase 1 - 06

The Negi-2B launched several more times from 1960 to 1961. The second launch on 1960 December 15 carried the Engineering Test Satellite "Neginohana," meaning "green onion flower" (the Imperial Seal of Hatsunia). This launch was to a polar orbit, which required launching south instead of east, and reduced payload capability as it was not in the same direction as Earth's rotation. Neginohana was the first use of solar panels on a Hatsunese satellite, and had a small television camera to transmit rudimentary black-and-white images of the Earth from space. The next two satellites, "Shinsei" and "Aozora," used a similar satellite bus design for observation of the space environment and atmosphere, respectively.


Neginohana in a polar orbit after being jettisoned from the Negi-2B third stage.


1961-04-01 - The "Shinsei" satellite, literally meaning "new star" or "nova," was launched to an orbit above 3000 kilometers. It had a cosmic ray detector as well as a micrometeorite detector.


1961-07-15 - The atmospheric analysis satellite "Aozora" ("blue sky") measured the temperature and pressure of the upper atmosphere, and an infrared radiometer to measure cloud temperatures. This was the precursor to proper weather satellites.
The radiometer consumed a relatively high amount of power, and so the instrument could not be operated all the time.

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Phase 2 - 01 - M-1 rocket, first communications satellite (1962)
Phase 2 - 01

The beginning of a new era.

The M-1 launch vehicle was a major leap in capabilities compared to the Negi-2B, as it was derived from an intermediate-range ballistic missile (IRBM) rather than a relatively large sounding rocket. In the late 1950s and early 1960s, the United States collaborated with its British and Hatsunese allies in the development of IRBMs because they had the range from those locations to be a deterrent to the Soviet Union. The US had developed the Thor missile, which used a single Rocketdyne LR79 engine, while the UK was developing the Blue Streak missile, which used two Rolls-Royce RZ.2 engines (a native-built version of the LR79). The Blue Streak would turn out to be too big and costly for the UK and was cancelled as a missile program, but would later find use in a future European launch vehicle. However, a Thor-like vehicle was considered effective enough for Hatsunia. Thus, the Y-1 ballistic missile (Y for Yokushi, or deterrence) was designed using Mikubishi's version of the LR79, called the LE-04, supplemented by two LE-04-1 (LR101-like) vernier engines for roll control. It was not an exact copy of the Thor, as the fuel tanks were shaped like a straight cylinder rather than tapering at the top.

The Y-1 was converted into a non-offensive satellite launch vehicle with the addition of the second stage, a stretched version of the one used on Negi-2B. The LE-03A engine had slightly higher thrust and efficiency compared to the LE-03, but the most important aspect was its ability to restart (previous engines could only ignite once). The reaction control thrusters now used hydrazine monopropellant instead of nitrous oxide. With both stages, up to 700 kilograms could be carried to Low Earth Orbit, and with the addition of a third kick stage, it could send up to 175 kilograms to a Geostationary Transfer Orbit (in which the satellite could raise its orbit and stay at the same place above the Earth) or 100 kilograms in a Trans-Lunar Injection maneuver. This rocket was called the M-1, with M standing for Miku/Mirai (future) or Mikubishi (thirty-nine diamond logo), and was similar to the Thor-Ablestar launch vehicle.

[context: The first orbital launcher of the National Space Development Agency of Japan was the N-I (not to be confused with the ill-fated Soviet N1), a license-built Thor-Delta rocket. While critical components of the N-I were built in the US and imported, the details of which were hidden from Japanese engineers in "black boxes," the M-1 was almost completely manufactured in Hatsunia.]


1962-01-16 - First launch of the M-1 carrying "Sakura" (cherry blossom), Hatsunia's first communications satellite. A larger launch pad was needed to handle the vehicle.


Sakura was placed in a low-medium Earth orbit with a perigee of 860 kilometers and an apogee above 6000 kilometers.
It provided the first trans-Pacific television signals, as well as wireless telephone transmissions, but could only do so for short periods of time due to the rotation of the Earth underneath the satellite.


The LE-04 is a gas-generator engine, meaning that some of the fuel and oxidizer is pre-burned to power the pumps and then discarded out the side, resulting in the darker exhaust. It is less complicated and expensive but also less efficient compared to closed-cycle engines.


The engine plume grows in size as atmospheric pressure lowers.


First/second stage separation


Payload fairing separation


Initial orbit


The LE-03A fires again on the other side

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Phase 2 - 02 - M-1, first weather, navigation, and recoverable satellites (1962)
Phase 2 - 02

1962-04-01 - "Himawari" (sunflower), the first "proper" weather satellite and the successor to Aozora (which was made for basic atmospheric analysis), was launched by an M-1 into a polar orbit. It was capable of observing cloud cover using small cameras [which I forgot to include in this KSP depiction], and measuring air temperature using infrared sensors in a more refined manner, transmitting vital data for meteorologists on the ground to make more accurate predictions and prepare for severe weather events such as typhoons.


1962-06-16 - "Ajisai" (hydrangea) was the first test of a navigation satellite system, also placed into a polar orbit, but slightly higher. By measuring the Doppler shift of the radio signals of a passing satellite with a known orbit, the position of a receiver on Earth could be determined. The US had a similar system, called Transit, meant for nuclear submarines (being adapted for civilian use later on). Hatsunia was reliant on international trade, especially via shipping. Better knowledge of a cargo freighter's position on the globe would result in more economically efficient paths between ports. The system would also be used by the Hatsunia Maritime Defense Force. Several more satellites would be needed to provide effective navigation coverage. Geodesy, or the measurement of Earth's shape and gravitational field, was another purpose for the satellite as it detected slight changes to its orbit.


(@Michel Van and @Loki-L, check this out)

1962-09-03 - "Tanpopo" (dandelion) was the first recoverable satellite of Hatsunia. Re-entry technologies such as heat shields were already being used by the two main superpowers to return people from low Earth orbit, and HASDA did not want to fall behind too much. Like the superpowers, the Hatsunia Ministry of Defense also saw the applications for reconnaissance, being able to return captured film from orbit. However, this was only a technological demonstration mission for now. HASDA provided a civilian and scientific purpose to this mission, planning to send animals and other organisms into orbit on future missions. It was also preparation for Hatsunia's first crewed spacecraft, which would take several years to develop due to lower budgets, and would require a larger launch vehicle. The satellite was divided into a return module, which was the only part which would survive the heat of re-entry, and a service module which contained avionics, a small hydrazine engine and RCS thrusters, and enough battery power for a few days of operation. Tanpopo spent a day in orbit before using its engine to de-orbit, re-entering and splashing down near the Nankai island chain west of Negishima and Minamikushi.


M-1 launching Tanpopo


After fairing separation


After spending almost one day in orbit


De-orbit burn


Separation of return module


Atmospheric re-entry


Parachute recovery

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Quite excited. Is there any missions involving fighter jets where potential astronauts are about to be trained for upcoming but possible manned mission? What would the name of possible first Hatsunese manned mission be?
Quite excited. Is there any missions involving fighter jets where potential astronauts are about to be trained for upcoming but possible manned mission? What would the name of possible first Hatsunese manned mission be?
They would probably happen in-universe, and the RP-1 career mode mod has contract missions for X-planes, but I won't be depicting them in this project. To save on loading time (it already takes about 5 minutes for the game to load) and because I only want to do space missions, I disabled the plane parts from loading (using a mod called Janitor's Closet). The first crewed mission is called "Utahime" (songstress/diva).
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Phase 2 - 03 - M-1, first long-range magnetospheric satellite and animal in orbit (1963)
Phase 2 - 03

1963-01-29 - "Jikiken" (magnetosphere) is the first Hatsunese spacecraft to go past a low/medium Earth orbit. Launched by the three-stage variant of the M-1 launch vehicle, the third stage was integrated with the spacecraft and surrounded by solar panels. As its name suggests, the primary mission of the spacecraft was to measure the strength of Earth's magnetic fields using a magnetometer between 300 kilometers above Earth's surface to over 240,000 kilometers, over half of the distance between the Earth and the Moon. The magnetometer was placed on an unfolding boom on one side to avoid interference from the rest of the satellite's electronics. A counterweight was added to the other side to avoid imbalancing the craft during the spin-stabilized third stage burn. Several other previously-used instruments were included to test their usage high above Earth. The omnidirectional antenna barely had a signal when transmitting from the maximum altitude.




In orbit, second stage performing spin-stablization before third stage separation and ignition. The magnetometer boom is still folded up.


Third stage burn


Initial deployment


At the maximum distance from Earth


1963-06-03 - Tanpopo-2 is the first mission to send an animal (a macaque) into orbit, further paving the way for human flight after the initial systems testing of the previous mission. The macaque was trained to handle the higher g-forces associated with launch and re-entry. The scientists were careful to give the passenger enough food, water, and oxygen to survive the one-day trip, and managed the on-board environmental control systems so there was no overheating or freezing. The macaque safely returned to Earth after Tanpopo-2 performed its automated de-orbit maneuver, with the return capsule splashing down just dozens of kilometers away from Negishima. Still, the mission came under some criticism from animal welfare advocacy groups.

Tanpopo-2 in orbit, with the biological life support container




After the brunt of re-entry, splashing down near Negishima



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Phase 2 - 04 - M-1, first lunar fly-by (1963)
Phase 2 - 04

1963-07-27 (1963-07-28 locally) - In this decade, Hatsunia was not developing huge mega-rockets to land humans on the Moon, but had enough of a budget to send small probes. The "Usagi" probe, named after the mythical rabbit that the dark markings ("seas"/"mare") on the Moon resembled in East Asian cultures, was launched by an M-1 rocket and sent on a lunar-bound trajectory. Like Jikiken, the probe was integrated with the third stage, but contained less instruments as it was only meant for short-term lunar observation. The antenna was built with a stronger signal gain to be able to transmit data from the Moon. The trans-Lunar injection maneuver, which accelerated Usagi by over 3.1 kilometers per second, was performed automatically while the spacecraft was not in range of any tracking stations, and it took several minutes until a signal could be confirmed. The timing had to be just right so that the probe would pass close to the Moon without hitting it. Two days after launch (1963-07-30), Usagi entered the Moon's gravitational sphere of influence and became the first Hatsunese spacecraft to visit another celestial body, transmitting pictures and basic data about the Moon and the space environment around it as it passed as close as 4486 kilometers from the lunar surface. The orientation of the solar panels was not ideal for gathering power, but was sufficient enough to accomplish the mission goals.

[context: In our timeline, the first lunar probe not from the Soviet Union or United States was from Japan... in 1990.]




Third stage separation and trans-Lunar injection


Halfway between the Earth and the Moon


Entering the Moon's sphere of influence



Another shot at periapsis with the Earth and Moon only

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Phase 2 - 05 - M-1, start of a communications network, first recon satellite (1964)
Phase 2 - 05

1964-02-12 - The Sakura-2a was launched as the first of a four-satellite communications network. This and the future Sakura-2b, 2c, and 2d satellites were planned to be spaced 90 degrees apart from each other to enable almost-constant communication relays in low Earth orbit. This required them to be at an altitude of about 2700 kilometers to preserve line-of-sight contact. The satellite needed to use a more efficient propellant compared to hydrazine (specific impulse of 198 s) to be able to achieve such an orbit after separation from the M-1 second stage. Thus, a bipropellant composed of Aerozine-50 and nitrogen tetroxide (specific impulse of 282 s) was used in the satellite's thrusters. Aerozine-50 is a a half-and-half mixture of hydrazine and unsymmetrical dimethylhydrazine originally developed by Aerojet.



1964-04-09 - IGS-1 (Information Gathering Satellite), the first reconnaissance satellite of Hatsunia, was launched by an M-1 with a larger-than-usual fairing. The launch and on-orbit operations were not managed by HASDA, but by the Cabinet Intelligence Office, which intended to perform reconnaissance checks on the Soviet bloc. The wider fairing accommodated a camera and film storage mechanism, and solar panels on one-half of the satellite. The payload remained attached to the M-1 second stage for orbital maneuvering, similar to the Corona/Discoverer satellite attached to the Agena upper stage. The film recovery capsule, nicknamed "Coconut," had its own small engine and some propellant to de-orbit and re-enter. The satellite was launched into a sun-synchronous polar orbit, meaning that it could pass over a certain point of the Earth's surface at the same local solar time every day. Launching a satellite this large to a slightly retrograde orbit (against the rotation of the Earth) pushed the M-1 to its limits. The first generation IGS program remained top secret until declassification in the 1990s.


M-1 with wide fairing

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Phase 2 - 06 - M-1, first geostationary satellite (1964)
Phase 2 - 06

1964-07-01 - After being launched by a three-stage M-1 rocket, Sakura-3 became the world's first geostationary satellite. This meant that it orbited over the equator at an altitude (about 36000 kilometers) at which the orbital period was the same as Earth's rotational period (23 hours, 56 minutes, and 4 seconds), so that it could effectively remain over the same area of the Earth and appear stationary when observed from the ground. The third kick stage accelerated the satellite to an elliptical and inclined geostationary transfer orbit, in which it waited for the Earth to rotate until the apogee was over the Pacific Ocean, near the International Date Line. Then, the satellite used its small thrusters to simultaneously circularize and reduce the orbital inclination from 26 degrees to 0 degrees. Sakura-3 had hinged solar panels that were folded up during launch, which then unfolded when in space to provide maximum solar exposure. The satellite was used to transmit messages between Hatsunia and the United States, and broadcast the 1964 Olympics in Miraito three months after launch.


Attached to M-1 second stage


Third stage burn


Waiting in GTO over the Atlantic Ocean


Circularization and plane change maneuver


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Phase 2 - 07 - M-1, second lunar fly-by and completion of MEO communications network (1964)
Phase 2 - 07

1964-09-21 (09-22 local) - The Usagi-2 was launched in the early morning to align with the Moon's orbital plane, and with better timing of the M-1 kick stage burn, achieved a closer flyby to the Moon at just over 1000 kilometers, two-and-a-half days later. The probe was equipped with a television camera with enhanced picture quality, the data from which took several days to transmit due to low antenna bandwidth, high power consumption, and multiple battery recharging cycles. The next lunar mission was planned to be an impact probe.


1964-11-02 - The Sakura-2 communications network in Medium Earth Orbit, with four satellites spaced 90 degrees from each other, was completed. This was mostly intended as a telemetry and data relay for most satellites in low Earth orbit. The altitudes of the satellites were just enough to not be blocked by Earth's horizon. The distance between each satellite (almost 13000 kilometers) was approaching the limit at which they could communicate with each other, but the effective data transfer rate remained the same as direct communication with a ground station.

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Phase 2 - 08 - M-1, magnetic field + weather sats, first lunar impactor (1965)
Phase 2 - 08

1965-04-01 - Jikiken-2 used a vector helium magnetometer (lighter than the previous version) to measure magnetic fields, a higher-resolution magnetic ion-mass spectrometer to determine the composition of particles in medium-high Earth orbit, and a scintillation counter to measure the energy from cosmic rays. Due to the heavier mass of the instruments, the probe only reached 90,000 kilometers instead of 240,000.


1965-06-12 - The Himawari-3 weather satellite carried a higher-resolution infrared radiometer (mounted on an extendable boom) to measure cloud and surface temperatures, and an infrared interferometer spectrometer gained insight into the structure and composition of the atmosphere. Eight folding solar panels made the satellite resemble its namesake, the sunflower.


1965-08-26 - Usagi-3 was the first lunar impact probe of Hatsunia. Because the spacecraft was designed to observe the lunar surface for only a few minutes, it did not carry a lot of specialized scientific equipment, while the TV camera was used to broadcast live images at a lower resolution so they could be transmitted quickly. The mass saved was used to give the probe additional reaction control system propellant for course corrections. The RCS could only translate forward or backward, so it could not target any location on the Moon, but it could make sure that the probe did hit the Moon. The probe arrived three-and-a-half days later (1965-08-29), impacting at over 2.5 kilometers per second in Oceanus Procellarum (the Ocean of Storms) north of Aristarchus Crater (bright white crater in the image below) and east of the smaller Väisälä crater.




Just before impact

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Phase 2 - 09 - M-1, comsat network replacement, second lunar impact (1966)
Phase 2 - 09

1966-02-13 - The Ajisai-5 navigation network, made of five satellites that were almost identical to the original Ajisai, was completed. The five satellites were in polar orbits spaced 36 degrees apart, and helped to determine the position of cargo ships traveling around the world, although it could not provide constant coverage.

1966-03-20 - A year after the launches of the Sakura-2 communications network in 1964, the solar panels turned out to be producing too little power due to the degradation of the cells. Thus, the Sakura-4 network was launched in 1966 (up to October 12) to replace the old network and ensure longer-term operations. The solar panels wrapping around the cylinder were replaced with four folding arrays to increase the maximum area exposed to the Sun while maintaining the same mass.


1966-07-22 - Three-and-a-half days after launch, the Usagi-4 probe impacted the Moon at the Montes Apenninus mountain range, near Mons Bradley and Mons Huygens.




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