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Eyes Turned Skywards

I must say that it has almost an air of unreality, when you contrast it with the nightmare that became planning and budgeting for Space Station Freedom, VentureStar, and Constellation (and now, yes, SLS) in our own timeline.

And yet, I can't say that it's entirely implausible, either.

It just shows how much more efficient Propellant Depots are for getting beyond LEO. By using Depot's you are building infrastructure to continue exploration instead of just visiting. Unfortunately I suspect that we are going to sink $30 Billion into SLS and only then will people realize how wrong that path was.
 
It just shows how much more efficient Propellant Depots are for getting beyond LEO. By using Depot's you are building infrastructure to continue exploration instead of just visiting. Unfortunately I suspect that we are going to sink $30 Billion into SLS and only then will people realize how wrong that path was.

Depots can certainly help with BEO operations, but right now, IOTL, we still don't know for sure how well LH2 can be stored for protracted periods without embrittlement of the storage tanks. ITTL, I have to assume they found a materials combination that permits it.

As for SLS? IOTL, Large Booster to send all the payload in one go is to date the only method that's ever been employed for BEO operations, so it's not that surprising they're sticking to what they already know, even though I can't see SLS working.
 
Depots can certainly help with BEO operations, but right now, IOTL, we still don't know for sure how well LH2 can be stored for protracted periods without embrittlement of the storage tanks. ITTL, I have to assume they found a materials combination that permits it.

As for SLS? IOTL, Large Booster to send all the payload in one go is to date the only method that's ever been employed for BEO operations, so it's not that surprising they're sticking to what they already know, even though I can't see SLS working.

Well, I have to point out that Saturn Heavy H03 has a payload to LEO that is actually very similar to SLS Block I, so it's not like our NASA isn't using large boosters. They do simplify some parts, especially if you don't have depots. It's just that their large booster is a version of their small booster, so that it doesn't cost all that much more to develop or to use than that small booster.
 
Well, I have to point out that Saturn Heavy H03 has a payload to LEO that is actually very similar to SLS Block I, so it's not like our NASA isn't using large boosters. They do simplify some parts, especially if you don't have depots. It's just that their large booster is a version of their small booster, so that it doesn't cost all that much more to develop or to use than that small booster.

Call it the Anti-Constellation Model.
 
Well, I have to point out that Saturn Heavy H03 has a payload to LEO that is actually very similar to SLS Block I, so it's not like our NASA isn't using large boosters. They do simplify some parts, especially if you don't have depots. It's just that their large booster is a version of their small booster, so that it doesn't cost all that much more to develop or to use than that small booster.

"Small" being what we call "heavy lift" today, 20 tonnes to LEO. Sigh.
 
Hello. For this week's illustration, we take a look inside the Orion "Shack".

orion_cut3.png
 
Been wanting this one for a long time

It's smaller than I expected on the interior, but the cutaway may be exaggerating that sense.

Where's the communications antenna(s)?
 
Well it's certainly...cosy.
It's smaller than I expected on the interior, but the cutaway may be exaggerating that sense.
A bit, yeah. And, of course, Orion's still not a proper base--just the "soonbase" NASA can accomplish rapidly.

It's not on the wiki as far as I can tell, but what are the specs for Orion?
Which specs are you looking for?
Where's the communications antenna(s)?
Call it "omitted for clarity". :)
 
A bit, yeah. And, of course, Orion's still not a proper base--just the "soonbase" NASA can accomplish rapidly.

Sure. And compared to the Apollo LM, it's a veritable shopping mall.

Still, for four people living together for a couple months...

Which part are they using for a solar flare shelter, if any? Is it the crew deck?
 
Which part are they using for a solar flare shelter, if any? Is it the crew deck?
I've gone back and forth--my initial assumption was that it'd be on the middeck, but it looked after more research that the dome's thickness (if it's like a Bigelow hab, it'd be about 15 cm thick) would make a solid start for flare protection, and there's less other equipment on that level. Currently, I'm inclined to say it's in the dome.
 
I've gone back and forth--my initial assumption was that it'd be on the middeck, but it looked after more research that the dome's thickness (if it's like a Bigelow hab, it'd be about 15 cm thick) would make a solid start for flare protection, and there's less other equipment on that level. Currently, I'm inclined to say it's in the dome.

That makes sense.

In OTL, SOHO has been able to give about an hour's warning for some time now, and I'd assume that similar capability exists in this timeline. That should be plenty of time to for the crew to hunker down.

Of course, that would not be an option for crew out on the mobile rover at any real distance from the Orion...
 
Part IV, Post 23: Japanese space probes
Eyes Turned Skywards, Part IV: Post #23

When Fukuro launched in late 2001, it was the end of a long era of Japanese planetary exploration. Since the launch of their first interplanetary probes fifteen years earlier, Japan’s planetary and comet exploration spacecraft had all been built to the same fundamental design drum-shaped design, based on communications satellite designs popular in the 1980s. Although variations on this basic design had served Japan well for fourteen years and four spacecraft, the design had been pushed to its limits for Fukuro, and it was obvious that new approaches would be needed for future missions such as the new Venus probe that Japanese Institute of Space and Astronautical Science, or ISAS, had recently begun.

In a fortuitous but entirely planned convergence, at the same time it was beginning to think about Fukuro’s successor ISAS was also putting the finishing touches on its new launch vehicle, the Mu-5 or M-V, a replacement for the series of Mu-3 vehicles it had relied on since the 1970s. While NASDA had led the H-I and H-II projects to develop a new, relatively large all-Japanese launch vehicle, ISAS had been heavily involved in the development of their solid rocket boosters, comparable to those used by American Delta rockets due to its lengthy experience in building and operating solid rocket motors. In turn, from the beginning of the H-I program it had been planned that these solid rocket boosters could be redeveloped into a standalone booster with a greater payload capacity and lower cost than the Mu-3 series. Such a booster would provide an independent, cheaper alternative to the H-I for scientific probes and other small spacecraft, and would provide useful experience with large solid rocket boosters and motors that could, perhaps, later be adapted to military roles. With the entry of the H-I into service, ISAS had turned its full attention to completing the Mu-5, and by the time Fukuro was sent into space was on the verge of performing its first test launch.

As Mu-5 development had started, ISAS had begun planning new missions that would take full advantage of the new booster’s capabilities, including Earth-orbital and deep-space missions. Besides a range of application missions focused on studying the Earth, Sun, and near-Earth environment, ISAS studied a broad set of beyond Earth-orbit missions, including lunar orbiters and landers, Venus and Mars spacecraft of several types, comet and asteroid flybys, landers, penetrators, and rendezvous missions, and several plans envisioning visits to more distant destinations, including Mercury, the asteroid belt, and even Jupiter. Preliminary study showed that only the nearer destinations were practical given available resources, both budgetary and technological, so that ISAS switched to a focus on what it termed its “three areas of interest,” the Moon, Mars and Venus, and the near-Earth comets and asteroids.

By the time ISAS was merged into JAXA in 2000, putting an end to the historically divided structure of the Japanese government’s space programs, mission studies in each of these areas had advanced significantly, leaving ISAS with a number of fleshed-out mission concepts that just needed the go-ahead to proceed to development. The new management quickly discarded the lunar mission concepts as redundant to JAXA’s cooperation with NASA, ESA, and Roscosmos on the Artemis program. Several months of further deliberation followed, with managers, scientists, and engineers debating the various merits of Venus, Mars, and asteroid missions, before a final decision was made to go with the Planet-V concept, a Venus orbiter targeted at atmospheric studies. For Japan’s first mission to another planet, Venus offered the advantages of a less demanding operational environment and shorter flight time than Mars, the destination of the Planet-M Mars orbiter which had been Planet-V’s main competition, much as it had for the United States or the Soviet Union back in the 1960s. And, given that no atmosphere-focused orbiters had visited Venus in nearly twenty years, any mission to the planet, Japanese or not, would clearly have high scientific productivity.

Following their usual practice, the Japanese announced Planet-V to the world as Planet-“C”, the third in their series of planetary spacecraft (one of the first, part of the Halley armada, had technically been classified as an engineering spacecraft). After the announcement, the Japanese buckled down to begin working on the probe, aiming for a launch date at the next practical window in 2004. As an entirely new design rather than a development of an older vehicle, Planet-C naturally faced more severe design challenges than other missions, and soon enough the program’s managers were having to push hard to have any chance of finishing the mission by the planned launch date. Nevertheless, they pushed, and the spacecraft was completed and launched by the Mu-5 on its third flight in March of 2004 before being successfully injected onto its interplanetary trajectory.

After launch, JAXA announced the spacecraft’s name: Akatsuki, or “Dawn,” an appropriate name for a spacecraft venturing inwards towards the Sun. Although Akatsuki remained largely dormant during the months-long cruise towards Venus, periodic status checks showed a plague of minor electrical faults, not severe enough to be a serious threat but a concerning sign so early in the mission. Unable to repair the spacecraft, however, mission controllers were forced to watch and wait, hoping that the faults would not worsen or proliferate enough to prevent Akatsuki from fulfilling its mission. As Akatsuki passed behind Venus before Venus orbit injection, anxiety rose to a fever pitch at mission control in Tokyo, only intensified by Fukuro’s ongoing difficulties. When the probe missed its first scheduled communications session after the orbital insertion burn, the control center was very nearly in total despair, fearing a repeat of Fukuro’s propulsion system failure. This time, however, such a failure would most likely mean a total mission loss, as Akatsuki’s attitude control thrusters were simply not powerful or efficient enough to brake it into Venus orbit.

The day after the first scheduled communications session, however, the Japanese deep-space antenna at Usuda picked up a faint signal from the direction of Venus. Further observations revealed the signature of the spacecraft’s carrier wave, and established that Akatsuki had fallen into safe mode. As reconstructed later by JAXA, it appears that Akatsuki successfully completed its orbital injection burn. Due to a design fault in the main transmission system, however, it had then suffered an electrical fault similar to those it had suffered during cruise as it powered up its transmission system and attempted to realign for its first Earth communication session. As a result, the probe suffered a severe systems failure, though fortunately not serious enough to completely knock out the spacecraft. Instead, it reverted to safe mode, stabilized its orbit, and began screaming for help over its low-gain antenna. Over the next several weeks controllers gradually returned the spacecraft to full functionality, though further electrical faults plagued efforts and attempts to reactivate the high-gain antenna had to be abandoned after the spacecraft repeatedly fell into safe mode while energizing the transmission systems. Nevertheless, they were able to restore the spacecraft to a semblance of full functionality, with all of the instruments functioning normally, and with the spacecraft in its planned elliptical science orbit.

Unfortunately, the loss of the main high-gain antenna severely curtailed the usefulness of those instruments by drastically limiting their ability to return data, as the low-gain antenna that mission controllers were now being forced to use had only been intended as an emergency engineering backup, and had a data rate of only a few dozen bits per second. It took little work to figure out that at that rate data from the spacecraft’s daily low-altitude passes would each take several days to transmit completely, drastically cutting into its scientific return. The only bright spot was that mission designers had already planned for the spacecraft to buffer and transmit its observational data, so that only relatively minor changes were needed to the spacecraft’s control software to accommodate its new state. Nevertheless, even the limited amount of data that could be returned by Akatsuki was more than enough to make a major scientific impact, with the probe providing significant information about the planet’s upper atmosphere and clouds. Only planned radio science experiments, which relied on the probe’s main antenna, had to be abandoned entirely; attempts to observe and characterize the planet’s powerful and frequent lightning strikes, to track upper-atmosphere circulation, and to study changes and structure in the atmosphere’s fine composition were carried out, largely successfully if on less data and less ability to quickly respond to observations than had been envisioned in the mission’s early design. By the time Akatsuki finally failed in early 2010, after nearly six years of operation, it had firmly established itself as an important milestone in the study of Venus.

While mission controllers were attempting to solve Akatsuki’s problems, their counterparts elsewhere in the agency were already beginning to work on its successor. While the Planet-V concept had appealed several years earlier due to simpler technical requirements, its Planet-M counterpart had not been abandoned, merely returned to the engineers for technical maturation and concept development. By 2004, it had been refined into a mission laser-focused on imaging the surface of the planet at higher resolution than any previous spacecraft, building on work done by Japan for Earth observation and spy satellites over the past decade. Despite limitations imposed by the lift capacity of the M-V rocket, modest technological development was projected to allow sub-meter optical resolutions, a factor of two improvement over the best available images of Mars from the American Mars Reconnaissance Pioneer satellite. Late in the year, several months after North Korea’s first nuclear test, JAXA received the go-ahead to begin work on what was now Planet-D.

Despite plans to reuse as much of Akatsuki’s basic design as possible to reduce costs, Japanese engineers were soon finding that they were having to completely redevelop many portions of the probe in order to adapt it to the cooler, dimmer environment of Mars and to avoid the electrical problems that had so heavily impacted the earlier mission, increasing expected mission cost. In an effort to minimize budgetary impacts, Planet-D’s launch was delayed from the originally expected 2005 to 2007, increasing overall costs but reducing yearly expenditures and providing more time to develop and assess the design changes that had accumulated from the older design. Fortunately, this extra time proved well spent after Planet-D’s launch in August and its cruise to Mars, which unlike Akatsuki’s to Venus was uneventful. Shortly after interplanetary injection, Planet-D also received a proper name: Hayabusa, or “peregrine falcon” in Japanese, for that bird’s penetrating eyesight.

After braking into Mars orbit in late May 2008, nearly a year after launch, Hayabusa began a program of aerobraking much like that carried out by the Mars Reconnaissance Pioneer some fifteen years earlier, dipping briefly into the planet’s upper atmosphere to slowly lower the high point of its orbit. Almost another year passed before it reached its final mapping orbit, only 300 kilometers above the Martian surface, and it began imaging the surface in earnest, gradually building up a high-resolution patchwork of the entire surface. Much as with Mars Reconnaissance Pioneer, this continual observation of the surface has led to the discovery of a considerable amount of seasonal and ephemeral activity, including the observation of several Martian dust devils and avalanches, and, perhaps more prominently, evidence of liquid seeps and flows on present day Mars. Early on during its mission, Hayabusa also discovered several apparently new impact craters that seemed to have exposed fresh water ice to the atmosphere, an important discovery that confirmed the presence of under-surface ice in at least some locations on Mars.

While Hayabusa was mapping Mars, Japan’s oldest active planetary spacecraft was finally nearing home. After suffering a severe propulsion failure in May 2003, Fukuro had been redirected, with the aid of trajectory planners at NASA’s Jet Propulsion Laboratory, onto a long, looping track that would send it flying past Mars twice to align it to intercept Earth in 2012, all that could be done without the spacecraft’s main rocket engine. One month before impact, JAXA commanded the spacecraft to perform its final maneuver, nearly depleting its remaining attitude-control propellant to ensure that it would hit the ground at Australia’s Woomera Test Range, the vast expanse of Australian outback that Fukuro had targeted since its launch, before ordering it to eject its sample capsule. A quartet of springs held in readiness since launch released, pushing the capsule bearing the precious grains of cometary dust that Fukuro had captured away from the spacecraft and towards the still-distant Earth.

Fukuro and its sample capsule reached Earth high above the waters of the Antarctic Ocean, carving a hard, bright path against the sky as they bit deep into their home planet’s atmosphere, slowing thousands of kilometers per hour in mere seconds. Before they could endure very much of this, Fukuro shattered, bursting into fragments that rained thinly on the southern coast of the continent, while the sample capsule, armored against the heat and stress of reentry, flew onwards towards Woomera. As it fell to merely supersonic speeds, it stirred for the first time since it had been dispatched by its carrier, ejecting a drogue parachute, then fired its main sail moments later as it slowed beneath the sound barrier, while also triggering a locator beacon. Australian and Japanese recovery helicopters were already in the air as it descended under its canopy, and within an hour of touching down on Australian soil it had already begun its journey to Tokyo’s Institute for Lunar Studies, where the samples would be carefully extracted and analyzed.

While Fukuro’s sample collector was being dissected, Japanese engineers were already hard at work guiding JAXA’s next planetary science mission towards its destination. With an active Venus mission and a Mars mission in development, Japanese scientists had quickly turned their attention back towards comets and asteroids. Just as Comet Halley had provided the first modest target for traveling beyond Earth orbit, so would these minor planets serve as relatively easy and straightforward targets for another advance in Japanese technology.

Since the 1980s and the American Kirchhoff and European Piazzi missions, the use of electric rockets, whether ion thrusters, Hall effect thrusters, or thermoelectric thrusters, had become commonplace for Earth-orbiting satellites, replacing older and less efficient maneuvering thrusters. The limited thrust available from electric rockets was not much of a drawback in this application, while the much higher specific impulse they offered compared to conventional cold-gas or monopropellant thrusters meant that satellites using electric rockets could serve much longer than previous designs. Although the Japanese aerospace industry was dominated by domestic concerns, these advantages still applied, and during the 1990s they had begun to develop electric rockets for their satellites as well. This development quickly caught the eye of ISAS, then the Japanese agency responsible for planetary exploration; the high specific impulse of electric rockets would permit their relatively small and payload-limited Mu rockets to lift more capable spacecraft, able to travel to more far-flung destinations or carry more instruments than would otherwise be possible.

First, however, the technology actually needed to be demonstrated on an operational spacecraft, rather than in a laboratory, or even on a satellite where they would be used intermittently rather than having to constantly fire for years to build up the necessary velocity changes. Comets and asteroids, many of which have elliptical or inclined orbits that are difficult to reach with conventional propulsion, and many of which are located in the inner solar system where temperatures are relatively mild and solar power abundant, were an obvious testbed for this work, and interest had been building in a technology-focused mission aimed at them even before Hayabusa formally started work, though it took several years of study and the freeing up of Hayabusa-related funding before work could start on this experimental spacecraft, named MUSES-B for “Mu Space Engineering Spacecraft” B at the time.

Such a mission would also offer the opportunity to test other new technologies that could be applied to future missions, such as more advanced computers, new data-transmission equipment, or more autonomous spacecraft control software. The most ambitious of the experiments that gradually accreted onto MUSES-B, however, was also its scientific centerpiece, a small penetrator intended to be fired from the spacecraft as it orbited an asteroid and, as the term “penetrator” implies, penetrate into its outer crust. Penetrators had been proposed for use exploring the Moon, Mars, and minor planets since the 1970s, and in theory had many potential advantages compared to conventional landers for exploring the upper subsurface of those bodies. However, for various reasons none had ever been launched, so that these advantages remained unproven. While small, the Japanese penetrator would at least begin to show whether or not penetrators were actually practical tools of inquiry. Even better, the penetrator could be used to demonstrate one of the newest and least-developed forms of asteroid deflection, kinetic bombardment, where a stream of projectiles would be launched to gradually change the orbit of a threatening body. By actually launching a small projectile into an asteroid, MUSES-B could show the effects such a projectile would have on the target body and experimentally demonstrate the velocity change that could be expected from such an object if it were used to deflect a threatening asteroid or comet. The role of the main spacecraft would be to transport the penetrator to the asteroid and serve as a communications relay between the penetrator and Earth, although it would also carry spectrometers to help extend the penetrator’s precise but localized compositional data to the rest of the body, and a camera for navigation and public relations purposes.

After more than five years of research and development, MUSES-B was launched aboard an M-V rocket in late 2012, bound for the asteroid Itokawa, which had been discovered only a few years earlier by one of the automated asteroid searches that had been created since the 1990s and renamed after the “father of Japanese rocketry,” Hideo Itokawa, after its selection as the target of MUSES-B. The spacecraft itself was renamed Yumi, or “bow,” while its accompanying penetrator was named Ya, or “arrow,” after the launch, as with usual Japanese practice. Shortly after injection into interplanetary space, Yumi began firing its ion engines, gradually building up speed as it flew towards Itokawa. It took more than two years for it to rendezvous with the asteroid, but earlier this year it finally reached Itokawa, and is currently settling into its final science orbit. Mission controllers say that they are preparing to fire Ya later this year, and are currently debating site selection using Yumi’s images of Itokawa’s surface.

For the future, JAXA has turned its attention back towards Mars, where it is considering another orbiter mission, or perhaps a small lander or penetrator network. There is even the possibility of cooperation on NASA’s planned Mars Sample Return mission next decade, although that is still some time away and may never come to pass. Nevertheless, the people of Japan still look skywards.
 
I haven't been reading this since April, so I needed to catch up.

About Japan's space program: there may be missions that happen a few years earlier, and are somewhat more successful than their OTL counterparts, as well as some projects whose OTL counterparts were cancelled (HOPE-X/C and the Centrifuge Lab), but for some reason, their launchers have remained mostly the same.

America, Russia (and India), as well as Europe have had drastically different launchers/launcher families, but Japan still has their Mu-Vs and H-IIs. (Unless they have different configurations, different propellants, or improved payload capacities compared to OTL)

(in other news, my Hatsunese Space Station "Mirai" is now in Orbiter, but is still a work in progress)
 
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About Japan's space program: there may be missions that happen a few years earlier, and are somewhat more successful than their OTL counterparts, as well as some projects whose OTL counterparts were cancelled (HOPE-X/C and the Centrifuge Lab), but for some reason, their launchers have remained mostly the same.
Well, there's a good reason for that. Japan, IOTL, essentially evolved their launchers from the Delta...which has not been significantly changed ITTL (yes, the Delta 4000 is rather bigger than any OTL Delta, but it uses the same basic technologies). So there's no particularly good reason for them to differ greatly in the 1980s or 1990s (well, there is the lack of Shuttles to inspire them...but on the other hand, the Deltas they were licensing already used solid rockets and, more latterly ITTL, hydrogen upper stages, and they began their LV development program by developing domestic upper stages both IOTL and ITTL, so there was still a good reason for them to go with "hydrolox core, solid boosters").

That being said, their launch vehicles here are different from their OTL counterparts. To take the example most relevant to this update, the Mu-V here has been based on the solid rocket boosters of the H-I/II, which rather than resembling the segmented solid rockets of the OTL H-II are monolithic solids like those used on the OTL H-IIA/B, instead of being a largely de novo development. It uses the designation Mu-V because ISAS had been using Mu as the name of its own launch vehicles since the 1960s, and had already used Mu-3 and Mu-4 in several different vehicles.

All that aside, we are less familiar with the Japanese space program than the others, so we were more hesitant to try to draw divergences. But there are plausible reasons to expect relatively little divergence until roughly now in the timeline.
 
interesting Mu-5 is still in Service iOTL is pull out service in 2006
seems JAXA keeps Mu-5 as launcher for smal payload, or want the Japanese Government keep it alive for potential military use ?

also has JAXA abandon there Solarsail craft project IKAROS in favor of Akatsuki.
 
Morning all. For this week's illustration, a look at Japan's Hayabusa probe as she uses the Martian atmosphere to trim her orbit.

hayabasi.png
 
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