JAXA+ | What if Japan had an unlimited space budget? | 2060-02-18 - Massive crewed missions to Jupiter, Venus, Mars, and more! [VIDEO]

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2039-05-21 - On the 29th anniversary of the launch of the Akatsuki Venus probe, the Ame-no-Uzume Venus Transport Vehicle began its journey from Earth. The eight LE-7-R engines of the first Earth Departure Stage burned to raise the orbit's high point by about 10,000 kilometers, before stage separation. Three-and-a-half hours later, the second EDS burned and separated, leaving the remaining vehicle on a course for Venus. Total change in velocity (delta-v): ~3400 m/s

First Earth Departure Stage burn - 1470 m/s

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First EDS separation

Second EDS burn -1961 m/s

Second EDS separation

2039-10-26 - After five months in interplanetary space, the Venus Transport Vehicle arrived at its destination. The six LE-7-R engines of the Venus Orbit Stage ignited to insert the craft into a 2-day elliptical orbit. On the next day, a plane change maneuver near the high point would align the orbit with the equatorial Venus (balloon) Habitation Module that arrived in April 2038. Two more orbital insertion burns would set up a relatively slow rendezvous with the VHM on October 28. Observing the relatively featureless (aside from a few ripples) cloud layer blanketing the entire Venusian surface, Asuka Tanoue would stay in orbit as Misora Kaneko and Kasumi Aimoto prepared to undock from the VTV in the Earth Arrival Vehicle to transfer and re-dock to the Venus balloon habitat. Total delta-v used: ~3650 m/s (and ~150 for plane change)

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First orbital insertion burn - 939 m/s

Plane change (to an equatorial orbit) - 149 m/s

Second orbital insertion burn - 1987 m/s

Third orbital insertion burn - 712 m/s

 

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2039-10-28 - Six years after the Kagutsuchi Mars landing, two crewmembers (Misora Kaneko and Kasumi Aimoto) undocked in the Earth Arrival Vehicle to make a short relocation from the Venus Transport Vehicle to the Venus Habitation Module. Once docked, the crew entered the small habitat, pressurized the cabin, and made preparations to de-orbit. The EAV undocked once again to make it back to the VTV, where Asuka Tanoue would remain in orbit.

The Earth Arrival Vehicle docked with the Venus Habitation Module in the foreground, with the Venus Transport Vehicle in the background

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EAV undocking

A short trip of a few hundred meters

The EAV making an automated return to the Venus transport

The Venus habitat/ascent vehicle before de-orbit

A couple hours later, the three LE-5B-3 engines of the VHM's orbital stage would light for one last time before being discarded and burnt up in the atmosphere. The VHM separated from the stage and inflated its 25 m heat shield, beginning its descent into the thick atmosphere. Large reaction control thrusters were needed to stabilize the vehicle, otherwise it would end up aerodynamically flipping with the heat shield in the rear and the less-resistant habitat and ascent vehicle in the front. During ballistic deceleration, the people onboard experienced high G-forces, up to 9 times that of Earth. This lead to momentary loss of consciousness, but they soon recovered after a few seconds. Much exercise was needed on the outbound journey to prepare the crew for this harrowing moment, which would be followed by wonder. At 75 km above the surface, the parachutes released, gradually slowing down the vehicle from hundreds to tens of m/s. At 60 km, the heat shield was jettisoned with slightly imbalanced solid fuel separation motors, to prevent the drag of the shield from causing a re-collision.

55 km was the suitable attitude for the parachutes to cut and the large balloon to inflate. The balloon itself had a mass of 23 t [ballast mass added based on the HAVOC concept], making up about one-quarter of the habitat + ascent vehicle (90 t). The hab descended as low as 49 km before it began to rise again, ultimately settling in at an altitude between 52.8 and 53.8 km. At this altitude, the pressures are relatively Earth-like (90-100 kPa) compared to the surface (over 9000 kPa), while the temperatures are around 50 °C instead of the lead-melting 460 °C. The gravity of Venus was also 90% that of Earth. The crew would stay in the atmospheric habitat, powered by four RTGs, for 30 days before returning to orbit in the Venus Ascent Vehicle.

[note: The KSP mods KerBalloons and AirPark (to suspend the vehicle in the air) were used. The KerBalloons part is only 15 kg and has a bug in which it explodes (if inflated) when loading a save file, so the file had to be edited to have the balloon uninflated when loading with AirPark.]

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De-orbit

Stage separation and heat shield inflation

Atmospheric entry

Parachute deployment

Heat shield jettison

A close-up of the habitat and ascent vehicle

 

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Misora Kaneko and Kasumi Aimoto stayed in the upper Venusian atmosphere for one month, above a vast majority of the thick carbon-dioxide-filled atmosphere which trapped heat to an excessive degree. However, the balloon habitat also had to be able to withstand clouds of sulfuric acid. The scientific mission was mainly to observe the weather and climate of Venus, including wind patterns and lightning, as well as how the atmosphere interacted with the surface. In a phenomenon known as super-rotation [not simulated in KSP], winds in the upper atmosphere circle the planet in only four Earth days while the ground takes 243 days to rotate. Another goal was to search for the possibility of life in the form of extremophile microorganisms floating in the upper atmosphere.

2039-11-27 - The Venus Ascent Vehicle was a two-stage "rockoon," 4 meters wide. A cylindrical crew cabin was surrounded by an aerodynamic shell, with methane/liquid oxygen rocket stages underneath. After the crew climbed down into the VAV, it detached and fell from the balloon habitat (at an altitude of 53.9 km), firing ullage motors (to settle the propellant) and igniting its single Raptor engine (borrowed from SpaceX). This methalox engine was chosen for its relative storability and high thrust compared to hydrogen, and efficiency compared to hypergolic fuels. As it began to rise again, the ascent vehicle was programmed to automatically tilt and avoid a collision, while being stabilized by vector thrust and four fins. The first stage burnt out at about 100 km, and was jettisoned. The second stage used three RL10 CECE methalox engines to reach an orbit of 220 km. Approximately 9200 m/s of delta-v was needed to reach orbit from 54 km, similar to the requirements for launching from Earth at sea level. Only one engine was used for orbital maneuvers. Several hours later, the VAV made a rendezvous with the Venus Transport Vehicle, docking at the saddle truss behind the VTV's habitation section. Misora and Kasumi had rejoined Asuka Tanoue, and were preparing to make it back to Earth.

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Initial drop

Second stage separation

In orbit

Approaching the VTV

 

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2039 -11-29 - Once the crew were all inside the Venus Transport Vehicle, the Ascent Vehicle undocked and was de-orbited. Like the Mars mission, departure from Venus happened in multiple phases, with a burn into an elliptical orbit (lasting 4 days), an inclination change near the high point, and a final escape burn on 2039-12-03. However, the remaining propellant on the Venus Orbit Stage was also used for one last boost (300 m/s) before the Earth Return Stage took over and used up over 4200 m/s of delta-v. The ERS had two LE-7-R and two LE-5B-3 engines.

Third and final phase of Trans-Earth Injection (1495 m/s)

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Venus Ascent Vehicle undocking

Trajectory planning needed the use of the KSP Trajectory Optimization Tool and another "dummy" object placed with HyperEdit.
The orbital maneuvers had to take place where the orbit crossed the equator, so that the plane change (green, Node 3) could be performed at the orbit's high point (apoapsis), reducing the change in velocity required.

First Trans-Earth Injection burn, and the final burn of the Venus Orbit Stage (300 m/s)

Second TEI burn (2500 m/s)

Plane change (229 m/s)

2040-11-03 - Because this mission was a short-stay (opposition class), Earth was not in an optimal position for a minimum-energy (Hohmann) transfer. Thus, the journey back to Earth ended up taking 11 months instead of 5 months, going as far as Mars's orbit around the Sun, so that the Earth could catch up in its orbit. Upon arrival, the VTV was travelling with over several km/s in excess velocity. The crew undocked in the Earth Arrival Vehicle, which was designed to propulsively brake using its LE-5B-3 engine (4400 m/s) approximately 10 minutes before entering the atmosphere, to reduce heating and G-forces during re-entry. Splashdown occurred in the Atlantic Ocean west of Africa.

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Interplanetary orbit, going as far as Mars

Earth Arrival Vehicle - propulsive deceleration (4400 m/s)

 

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In the 2040s, JAXA+ planned to send two crewed missions to the Asteroid Belt between Mars and Jupiter. The Koujin mission (named after the Japanese god of the hearth and kitchen) would go to Vesta, while the Inari mission (named after the Japanese god of rice, agriculture, and prosperity) would go to Ceres. Both missions would use identical hardware, the habitats and landers sent first in 2043, followed by the crewed transports in 2044 and 2045.

This would be the first use of nuclear thermal propulsion (NTP) on a mission. Nuclear power was considered controversial in Japan after the 2011 Tohoku earthquake and tsunami, leading to the meltdown of the Fukushima power plant . However, by the 2020s, Japan was restarting its nuclear plants. There was still some reluctance to utilize nuclear power* unless it was necessary or practical, such as powering a base for long lunar nights. As JAXA+ started to aim beyond the inner solar system, nuclear energy would be needed for efficient engines (about twice the specific impulse of chemical propulsion) and powering spacecraft where sunlight was weak. Two engines were developed: the small LE-N engine (based on the SNTP-PFE100, 245.2 kN of thrust) and the massive LE-N2 (based on the NERVA II, 867 kN of thrust). The engine designs were modified to use low enriched uranium (LEU)**, which could not be used for nuclear weapons (the mythological deity Koujin also represented "violent forces that are turned toward the betterment of humankind").

*As a side note, sentiment against nuclear power after Fukushima led to the building of more coal plants instead of renewables (which are land-constrained)
**I do not know how that would affect performance

The NTP engines used pure liquid hydrogen instead of hydrolox, meaning less dense and much larger propellant tanks (from 10 to 13.9 m diameter). Each mission would launch 7 rockets mostly consisting of the H-Z 122XL, a variant using a single extended core stage, two liquid and two solid rocket boosters, and an extra large fairing (19 m diameter) to accommodate the larger stages. It would be able to lift between 750 to 800 tonnes to low Earth orbit.

The interplanetary transport habitat launched by the H-Z 102L had a larger 25 m centrifuge ring, able to generate 0.5 Gs. The crew would primarily live in the rigid sections comprising one-fourth of the inflatable ring, surrounded by a total of 50 tonnes of radiation shielding to reduce exposure to cosmic rays. The heavy shielding would result in the transport weighing over 3600 tonnes, while the surface habitat and transfer stages only weighed 760 tonnes.

(note: I had to change the Kerbalism config files to make the ring shieldable, and reduce the surface area for shielding)

edit 2023-01-23: I underestimated the amount of hydrogen needed for refueling, so I have revised the mission plan with one more tanker launch.

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2042-12-29 - A Zeta rocket (with a 9 m wide fairing) launched from Uchinoura Space Center with three relay satellites to Vesta. Each had a mass of about 900 kg. The 5 m nuclear stage used a single LE-N engine and was almost 50 tonnes, and had drop tanks to increase maximum Delta-v. A distant flyby of the Moon occurred less than a day after launch.
Earth-Vesta transfer burn Delta-v (c. 2043): ~4300 m/s

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Drop tank jettison

Fly-by of the Moon

2043-01-05 - An H-Z 122XL launched the Koujin surface habitat and lander to Vesta. The first nuclear stage used two LE-N2 engines, followed by a single LE-N2. Both the habitat and relay satellites would reach Vesta in January 2044.

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Second in a series of two burns

Trajectory to Vesta

 

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2043-05-22 - Another trio of relay satellites was launched to Ceres. This time, launching in full daylight.
Earth-Ceres transfer burn Delta-v (in 2043): ~5000 m/s

[edit: Due to underestimations of fuel by MechJeb during orbital insertion at Ceres (it assumed that the satellites would detach prior to insertion), the mission was redesigned / retconned. The core diameter is now 6 m instead of 5, with a total mass of 68 t, and is launched by an H-Z 102L rocket instead of a Zeta.]

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2043-05-28 - The "Inari" mission to Ceres began with the launch of the surface habitat and landing modules. After Trans-Ceres Injection, the first nuclear transfer stage ran of fuel and was jettisoned early. It would arrive at Ceres in January 2045, about 1 year after the arrival of the Koujin habitat at Vesta.

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2044-01-09 - Three DRTS relay satellites arrived at Vesta. The LE-N transfer stage braked into an elliptical orbit before transferring to a semi-synchronous equatorial orbit (almost 11 hours) with an altitude of 600 km and jettisoning the satellites, which moved into their triangular positions by January 12. Vesta took just over 5 hours to rotate, but a synchronous orbit of 280 km could not have line-of-sight communications for a trio of satellites.

Vesta capture burn Delta-v (in 2044): 5200-5300 m/s

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2044-01-11 - The Koujin surface habitat and lander module arrived at Vesta. From an elliptical orbit, it lowered itself down to an 90 km orbit (36 degree inclination), aligned in such a way for the crew to depart to Earth with a minimal change in velocity. The habitat and lander modules deployed their solar panels and were released from the transfer stage. The lander module would remain in orbit for the crew to arrive by the end of 2045, while the habitat made its descent using two RL10 engines, touching down in the middle of Marcia Crater on January 13 (JST) and deploying drills to mine regolith for radiation shielding.

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2044-02-14 - An H-Z 122XL rocket takes off with the first components of the Koujin Vesta crew transport, the Earth Return Stage and Asteroid Orbit Stage, to a 400 km parking orbit. The stages have a diameter of 13.9 m and are launched partially fueled.
2044-03-09 - (H-Z 122XL) The central Earth Departure Stage launches and docks to the rear of the AOS using a new annular docking ring.
2044-04-02 - (H-Z 122XL) The first Earth Departure Stage Booster, which docks to the side of the EDS. Two pairs of docking ports are used for stability.
2044-04-27 - (H-Z 122XL) The second Earth Departure Stage Booster, which docks to the other side. The boosters are designed to remain attached to the central EDS (and not separate).
2044-05-20 - (H-Z 122XL) The Tanker-L, which mostly refuels the transport vehicle with liquid hydrogen but not completely [as I discovered].
2044-06-01 - (H-Z 104XL) The Tanker-S, a shorter version which does the rest of the refueling. Undocking of the tankers is performed shortly after.
2044-06-14 - (H-Z 102L) The transport habitat (with 50 tonnes of radiation shielding) and Earth Arrival Vehicle launch with three astronauts: Heisuke Koishi, Rena Minase, and Takeshi Kakoi. Over a day later, it docks to the front of the ERS and inflates the 25 m centrifugal gravity ring.
2044-06-21 - Starting with a mass of 3650 tonnes, the Koujin Vesta transport leaves Earth over a series of two burns (total ~4800 m/s). It will reach Vesta in December 2045, coinciding with the Inari crew transport's departure for Ceres.

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Earth Return Stage / Asteroid Orbit Stage (launch)

Earth Departure Stage docking (launch)

EDS booster 1 (launch)

EDS booster 2 (launch)

Tanker-L (launch)

Tanker-S (launch, undocking)

Transport hab, EAV, and crew (launch)

Second burn

 

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2045-01-12 - Three relay satellites (DRTS-X13 to15) inserted into a 9-hour stationary orbit over 720 km above Ceres. They arrived in their final positions on January 15.

[Due to underestimations of fuel by MechJeb during orbital insertion at Ceres (it assumed that the satellites would detach prior to insertion), the mission was redesigned / retconned. The core diameter is now 6 m instead of 5, with a total mass of 68 t, and is launched by an H-Z 102L rocket instead of a Zeta.]

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2045-01-18 - The Inari habitat and landing modules arrived at Ceres, entering a low orbit between 80 and 90 km on the next day and using up a total of 5900 m/s of Delta-v. The habitat landed in Occator Crater on January 20 while the crew lander would remain in orbit until 2047.

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2045-12-14 - The Koujin crew transport arrived at Vesta. The last of the Earth Departure Stage's fuel was used to brake about 200 m/s, then detached. The Asteroid Orbit Stage burned for over 4500 m/s of Delta-v, making several maneuvers to intercept the Landing Module in low Vesta orbit (90 km) on December 17. Once it got close, the lander performed an automated docking with the transport. Heisuke Koishi, Takeshi Kakoi, and Rena Minase boarded the lander, which undocked and de-orbited using five LEROS-4 engines (1.3 kN each) to land in Marcia Crater on December 18. After planting the flag, the crew made long, floating strides in the low gravity to the Habitation Module (over 100 m away), which they would stay in for over 9 months.

At the same time, the Inari mission was getting ready to send another three astronauts to Ceres.

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Using the last of the Earth Departure Stage's fuel

Earth Return Stage used for rendezvous

Landing Module (arrived in 2044) docks

De-orbit

Heading to the base

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2045-07-24 - Several months before the Koujin mission landed people on Vesta, construction of the Inari Ceres transport had already begun.

2045-12-13 - After assembly and refueling, the crew of the Inari mission lifted off. Kei Nagase, Takahide Ishikawa, and Hikari Tsuchiyama docked to the massive vessel. On December 21, the spacecraft began its two-part transfer burn to Ceres, to arrive in February 2047.

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2045-07-24 - Earth Return / Asteroid Orbit stages

2045-08-20 - Earth Departure Stage

2045-09-12 - Earth Departure Stage Booster 1

2045-10-06 - Earth Departure Stage Booster 2

2045-10-30 - First refueling tanker

2045-11-22 - Second refueling tanker

2045-12-13 - Crew launch

2045-12-22 - Second Earth departure burn

 

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9 months at 0.025 g? How’re they going to maintain their muscle and bone masses? I’d think one of the greatest challenges would be simply moving around on the surface. The same will go for Ceres (I didn’t know, until I looked it up, that Vesta and Ceres have roughly the same gravity, despite the significant size–and therefore density–difference. Interesting!), too.

At this point, I was thinking that they would have cybernetic implants (developed in the 2030s) that assist bodily functions in low gravity (this was a plot point in a 2022 animated series called The Orbital Children, which also takes place in 2045).
There is also enough gravity to "walk," although it's very slow and floaty.

2045-12-24 - Heisuke Koishi, Rena Minase, and Takeshi Kakoi boarded the Vesta Cruiser and drove over 10 km to the east in Marcia Crater, which was the largest and youngest of the three "snowman craters," the others being Calpurnia and Minucia. The surface of the crater is mostly made of basaltic rock (known as eucrite) and is rich in iron. Due to the low gravity, wheel traction was also lower, and the motor was set to 5% of normal power to avoid excess torque.

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2046-09-20 - After nine months, the three crew members left the surface habitat, using the small landing module to easily launch back into orbit and dock with the interplanetary transport. On September 26, the transport ignited its single LE-N2 engine to return to Earth (~4800 m/s).

2046-09-26 - Departure from Vesta

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2047-02-07 - After 1 year and 2 months, the Inari crew transport finally arrived at Ceres, slowing down by over 5000 m/s to meet up with the landing module in a 90 km orbit on February 9. On February 10, the powered descent and landing commenced. Kei Nagase, Takahide Ishikawa, and Hikari Tsuchiyama became the first Japanese astronauts to set foot on the largest object in the asteroid belt. Over the next 6 months (a shorter stay due to transfer windows), they would live in the surface base on Occator Crater. On February 15, they explored the crater in the Ceres Cruiser, driving 20 km south and up the central hill. Occator was known for its bright spots, which were made of salt deposits (mostly sodium carbonate) left behind when briny underground water rose to the surface through cryovolcanism. The water had already sublimated into the vacuum of space, and the process could still be happening today.

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2047-08-06 - The Koujin Vesta crew transport returned to Earth after a journey of over 3 years. The Earth Arrival Vehicle undocked and decelerated by over 4000 m/s using its LE-N engine. After the capsule separated, the nuclear stage boosted out of the way to avoid entering Earth's atmosphere. Heisuke Koishi, Takeshi Kakoi, and Rena Minase splashed down off the western coast of Borneo in Indonesia.

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2047-08-10 - The crew of the Inari mission only stayed six months on Ceres, due to the different launch windows from Vesta. The next launch windows were 4 months from now (requiring an additional 1000 m/s in Delta-v for the Ceres-Earth transfer), or waiting another one-and-a-half years. After docking with the transport, they began their return trip on August 16.

2047-08-16 - Leaving Ceres

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2048-12-20 - After over another year in space, Kei Nagase, Takahide Ishikawa, and Hikari Tsuchiyama undocked in the Earth Arrival Vehicle, slowing down by 4900 m/s before entering Earth's atmosphere and splashing down in the Caribbean Sea.

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Comparison of interplanetary ships (Mars, Venus, Vesta and Ceres)

 

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After sending humans to the Moon, Mars, Venus, and asteroids, JAXA+ was now ready to venture into the outer solar system. The Raijin mission, named after the Japanese god of lightning and thunder, would transport 3 astronauts to two of Jupiter's major moons (discovered by Galileo) in the 2050s. They would stay a few months at a pre-deployed base on Callisto, then briefly land on Ganymede. The other two Galilean moons, Europa and Io, were not an option as they were deep inside Jupiter's radiation belts. The longer duration of the mission in interplanetary space required heavier radiation shielding and more propellant, resulting in the initial mass of the piloted vehicle approaching 6000 tonnes.

A new launch vehicle, the H-ZA, was developed to carry payloads up to 1070 tonnes (fact sheet), about twice the lift capacity of the Sea Dragon. The core stage diameter was widened to 21 meters, and the fairing to 26 meters. It had 19 LE-Z engines on the first stage with up to 8 SRB-Z boosters (a total of 11 times the Saturn V's launch thrust), and 4 LE-Z vacuum engines on the second stage.

(I made a custom patch to add gold foil textures to the ROTanks mod.)

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Tanegashima model by Tyler Raiz. Instead of using the Kerbal Konstructs mod like in their video (which causes the custom island model to disappear at a certain distance), I had to:

- resize the island to a more reasonable (but not exact) size
- edit the Earth heightmap .dds, replacing the default terrain with water (so it doesn't intersect with the new island model)
- move the space center in LaunchSites.cfg
- create a patch to use the PQS City2 function of the Kopernicus mod to have the island visible at longer distances (like in Katniss's Cape Canaveral mod)

A test launch lifting a 1000 t liquid hydrogen tank into low Earth orbit

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2049-09-30 - Three DRTS-X relay satellites (DRTS-X16, 17, and 18) were launched by an H-Z 102 rocket to Callisto. These satellites were powered by RTGs as sunlight was less powerful at Jupiter's distance. They would reach Jupiter by the end of 2052, and arrive at Callisto in early 2053.

Advances in materials allowed for the construction of lighter hydrogen fuel tanks that could carry more propellant in the same volume. A propulsion bus similar to the one used for the Ceres comsat network could thus be used to take the trio of satellites all the way to Callisto orbit.
(meta note: the new version of Realism Overhaul for KSP 1.12 changed tank masses when LH2 is loaded)

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2050-10-01 - One year after the comsats were launched, the first module of the Raijin Jupiter Cargo Vehicle (JCV) was launched by an H-ZA 208 rocket. It weighed over 1000 tonnes at launch and consisted of the Earth Departure Stage (21 m diameter, 2 LE-N engines) and Jupiter Orbit Stage (13.9 m, 1 LE-N engine).

2050-10-27 - An H-Z 102 launched the Jovian Moons Landing Module (JMLM) and Callisto Habitation Module (CaHM) to rendezvous and dock with the JCV using a auxiliary propulsion stage. After arriving in Callisto orbit, the CaHM would proceed to land on the surface while the JMLM would remain in orbit until the crew arrived. A propellant cache would refuel the lander after the stay on Callisto, so it could land and take off from Ganymede after being pushed there by another vehicle.

On October 30, the Trans-Jovian Injection was performed, to arrive in early 2054. It was split into three burns (1400 + 1500 + 3700 = 6600 m/s) due to the relatively low thrust of the LE-N engines.

Third trans-Jovian burn (after stage separation)

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1st burn (apogee)

2nd burn (apogee)

 

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2052-12-27 - The Data Relay satellites were the first to arrive in the Jupiter system. Just over a month later (2053-02-06), the three satellites settled into 8-hour equatorial orbits 2900 km above Callisto.

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2054-01-19 - The Jupiter Cargo Vehicle performed orbital insertion and reached Callisto in late February 2054. After entering a 500 km parking orbit, the Callisto Habitation Module and Jovian Moons Landing Module separated from the transfer stage. On Feburary 26, the CaHM used its 4 RL10 engines to descend to 100 km before landing in a flat equatorial area where Jupiter could be visible just above the horizon. Like the Tsukuyomi Moon base, which had to be powered for several days without sunlight, it used a Kilopower nuclear reactor and needed large radiators to dissipate heat.

Callisto had been selected for its safe distance from Jupiter’s radiation belts. Ganymede is at the innermost limit, while Europa and Io are constantly bombarded by radiation.

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2054-09-26 - The first module of the Raijin Jupiter Piloted Vehicle, consisting of the Earth Return Stage and Jupiter Orbit Stage, was launched into a 400 km orbit by an H-ZA 208 rocket. Over the next six months, six more H-ZA 208s would launch the three parts of the Earth Departure Stage, as well as three refueling tankers. On March 9, 2055, the crew of the Raijin mission launched: mission commander Hachirota Hoshino (whose girlfriend worked in orbital debris cleanup), engineer Ken’ichi Obikawa, and scientist Juri Araki. The crew vehicle and orbital habitat brought the total mass of the JPV to 5700 tonnes in low Earth orbit. The JPV began its departure in two parts from March 12 to 14, changing its velocity by a total of 6500 m/s (2900 + 3600) for a 2 year journey to the Jupiter system.

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2054-09-12 - Launch of Earth Return Stage and Jupiter Orbit Stage

2054-10-08 - Launch of Earth Departure Stage

2054-11-02 - Launch of Earth Departure Stage B1

2054-11-27 - Launch of Earth Departure Stage B2

2054-12-23 - Launch of Refueling Tanker 1

2054-01-17 - Launch of Refueling Tanker 2

2055-02-11 - Launch of Refueling Tanker 3

2055-03-09 - Launch of Raijin crew and orbital habitat