Eyes Turned Skywards

e of pi and I have agreed that our remaining buffer is sufficiently full, so we are going to resume posting starting this Friday, July 24th, and continuing every Friday after that. Since I am a feckless graduate student and e of pi is a Hardworking American(c), I will be taking posting duties for this last part (except possibly for one Friday in August when I will be out of town and may not be able to post myself).

Ha! Another reason to celebrate the 24th for me! (Hint: Here in Utah the 4th of July is called "that OTHER holiday in July" fer a reason ;) )

Part IV, Post 21: American unmanned exploration
Eyes Turned Skywards, Part IV: Post #21

Even as their colleagues elsewhere were fighting to keep the Pioneer program going, the scientists and engineers working on the Hermes Mercury orbiter mission were steadily working towards their mission’s launch. Optimistic and aggressive early projections of launching in 2005 had run into the cold--or in this case, hot--reality of dealing with the harsh environment of Mercury orbit and forced a slip, but after recalibrating expectations mission development was going smoothly and on-time. The largest impact had been the addition of an Earth flyby before beginning the main flyby sequence to reach Mercury orbit, an optimization that permitted a slip of only seven months instead of nearly two years to the next Venus launch window. This would, admittedly, increase mission duration and risk, but the extra time would be spent in a relatively calm and quiet region of space, hopefully keeping the spacecraft safe and operational.

Unfortunately, budgetary impacts were not so limited; as the first and possibly the only spacecraft to reach Mercury orbit for some time, the Hermes proposal had included a relatively large number of instruments in order to probe the entire geophysical environment of the planet. Although most of the instruments had been relatively well understood and developed, the complications of modifying them to deal with the Mercury environment and integrating them into the spacecraft had proven more difficult than expected, another reason for the mission’s slip. To avoid further delays, additional funds were poured into the project, one of the factors behind the delayed 2006 mission selection. Although effective at keeping the program on-track, the cost growth of the mission had led to questions during the reorganization of the Pioneer program about whether it was meeting its goals of enabling cheap, rapid exploration, despite the spacecraft’s successful launch only a few months after the cancelled selection.

As NASA organized an abbreviated selection in 2007 to compensate for the cancellation of the 2006 selection, the board responsible was acutely aware that future Congressional support could very well be riding on whether the mission they picked was a successful exemplar of the program’s purpose or bloated and delayed by unexpected cost growth and technical issues. In a stroke of what could be called fortune, however, all of the proposals for the 2007 selection were repeats of proposals from the planned 2006 selection, as it was not possible for other teams to assemble their proposals fast enough to meet submission deadlines, and in turn were usually submissions of proposals that had previously gone through at least one Pioneer competition, since only larger, better-resourced teams could invest in suddenly updating their proposal documents to account for the new date. As a result, when the board met to consider its choices, it was selecting from a list of well-studied missions with extensive costing data, leaving very few unknown unknowns to anticipate. Even with this confidence, however, the selection of the Mars Polar Lander, or MPL, indicated that the board was breaking for the safe choice over more adventurous alternatives.

Proposed in every competitive Pioneer selection from 1999 onwards, MPL was exactly and precisely what its name indicated, a fixed lander, like the Vikings, designed to land near one of the Martian poles and investigate the near-polar environment of Mars. Landing constraints on all previous Mars missions, whether Soviet or American, had prevented spacecraft from landing near either pole, a disappointment to scientists who wanted to explore the only polar ice caps in the Solar System aside from Earth’s. Besides being interesting subjects of exploration in their own right, their growth and shrinkage over the course of the Martian year has a measurable impact on the Martian atmosphere, with nearly a third of the atmosphere’s entire mass freezing out during winters and sublimating back into gas during the spring, piquing the interest of climatologists, while they are surrounded by and contain many complex and interesting geological structures, like layered terrain and underground water ice deposits. An offshoot of the pre-Pioneer Mars/Phobos ‘98 Ares Program mission proposal, which was ended by Gore’s election and reorganization of Project Constellation, the JPL-led spacecraft would land during the northern summer, spending several months exploring the weather and surface of a polar site before dying as temperatures plunged with the onset of winter.

Although the mission had seen a great deal of study and refinement in the decade and a half it had taken to go from proposal to selection, and promised to stick to well-understood technology and well-understood risks, for this very reason its selection immediately saw criticism from some corners of the planetary science community who thought it showed a stodgy, conservative attitude completely at odds with the purpose of the Pioneer program. Probes like Barnard, still three years from its encounter with Comet Encke, or Hermes, about to flyby Earth on the way to Venus, had pushed the envelope, venturing to new places and daring to do new things that would be impossible with more expensive missions. A spacecraft that would recapitulate probes from thirty years earlier hardly had their air of romanticism and exploration, even if it was venturing to a new destination on Mars; even, perhaps especially, if it was a firmer budgetary and schedule choice than more adventurous missions. Nevertheless, most members of the community, aware of the criticism that had been leveled at Hermes, understood NASA’s desire to stick to the tried-and-true, and lined up behind the selection, leaving the critics as persistent gadflies, but nothing more for the moment. As work at Pasadena got underway, however, and attention elsewhere turned towards the next selection, their position would become increasingly important and influential.

Thus, as the next set of Pioneer proposals began to roll in the next year, the attitude of the selection board had moved from sheer conservatism towards an attempt at blending careful conservatism and adventurousness in a single mission, much like Hermes had done. Although selecting missions unlikely to overrun their estimated budgets was important, so was a sense of adventure. Accommodating both of these desires was difficult, with many worthy missions at hand, but ultimately the board decided that the best balance for the 2009 selection was offered by the Venus Atmospheric System Explorer, or VASE, mission, an update of 1978’s Pioneer Venus Multiprobe mission to meet a new era of technology and a new set of scientific questions. By using a well-understood mission profile and operating inside the envelope, the board felt that it posed few financial or schedule risks, while at the same time it offered attractive prospects for novelty by traveling to one of the harshest planets in the solar system, and one that no American spacecraft had traveled to in fifteen years.

VASE itself had grown out of a series of studies and mission concepts developed by the Venus science community since the demise of VOIR, which had developed a consensus that the most important questions about Venus concerned its atmosphere. Despite the Eos Franco-Soviet balloon mission of the early 1980s, the Pioneer Venus multiprobe mission a few years earlier, and even earlier Soviet atmospheric probes, much was still unknown about the structure and fine composition of the atmosphere, and therefore about the history of the planet. Compared to orbiters like the recent Japanese Akatsuki and Chinese Jinxing spacecraft, atmospheric probes could explore the denser, higher-pressure region under the cloud deck, providing otherwise unobtainable information and complementing orbital observations. Similarly, a modern balloon mission, using more advanced electronics and equipment than the old Eos mission, could provide more information on the atmosphere in more places at the same time. Despite this scientific attraction, atmospheric missions were also much less ambitious than many of the alternatives, avoiding the harsher regions of Venus or the need to survive them for long periods of time.

However, even lower ambition only went so far in reducing cost and schedule risks. Although the Venus Exploring Inflatable Lifter, or VEIL, mission had proposed a Venus balloon and at first glance seemed a strong competitor to VASE, it had been heavily compromised in order to fit in the Pioneer budget box. Venus scientists wanted multiple balloons at multiple latitudes and longitudes in order to track wind currents at different locations on Venus, grist for the mill of computational models that they could then use to extend their observations to the rest of the atmosphere. In addition, they wanted the ability to track balloon movement anywhere on the planet, in turn requiring a communications relay orbiter for when the balloons were inconveniently on the side facing away from Earth. Together, this meant much higher costs, in the range of a Cornerstone mission, so that VEIL had pared the mission back dramatically, only delivering a single balloon with no communications relay satellite. Although this managed to reduce the mission’s projected cost to acceptable levels, it also reduced its scientific value so much that it hardly seemed worthwhile any more, while still throwing up a number of red flags for potential overruns and schedule slips in the making. As much as many people wanted the Pioneer missions to push the envelope, they could only push so far. Ultimately, even one balloon had proved a bridge too far for Pioneer’s budgets, and VEIL had lost out in favor of VASE.

For more ambitious missions, scientists would have to look towards the Planetary Science Prioritization Panel, or PSP^2, as it began working on its legally-mandated report on the future of planetary science soon after the selection of VASE. Since the 1960s, the National Academy of Sciences COMmittee on Planetary and Lunar EXploration, or COMPLEX, had periodically produced reports on recommended future planetary science missions, many of which had eventually been flown, but in a haphazard and demand-driven process. Unlike other expensive fields like particle physics, nuclear physics, or astronomy, there was no statutory structure for providing recommendations to guide and shape NASA’s planetary science program, with the result that it had evolved to launch missions based at least as much on political as scientific criteria. This had worked well in the afterglow of Apollo and the Vulkan Panic, when relatively loose budgets had permitted a wide-ranging and pioneering program of exploration, but had become ineffective in the more straitened circumstances of the 1990s. One of the primary recommendations of the Cornell Plan had been to establish a permanent advisory body like the Particle Physics Project Prioritization Panel or Nuclear Science Advisory Committees advising the Department of Energy and National Science Foundation on their fields, but for planetary science. This body would be responsible for regularly providing a list of recommended missions to NASA, which the agency could then choose from. With its establishment by Congress, PSP^2 was now beginning to draw up its first report with the development of studies on a wide range of possible missions and destinations by specialized panels including many of the most distinguished scientists in the field. Each of the five major groups of target bodies--terrestrial planets, Mars, gas giants, icy bodies, and minor planets--had its own survey panel, along with “interdisciplinary” survey panels covering technology development and supporting infrastructure. Over the course of the year, PSP^2 sorted out the responsibilities of the panels and began a concerted program of community outreach, even as the panels, in turn, began to write up their own studies for the main committee.

As the first drafts of the panel studies began to come in later in the year, it became clear that PSP^2 would, at least, not suffer from a lack of mission possibilities to choose from. Over two dozen serious proposals had been mooted and studied by the target panels, ranging from a large mission to follow up Hermes and perhaps even attempt a landing on Mercury’s surface to an ion-propelled, Saturn Heavy-boosted spacecraft that would zoom past Jupiter before screaming out into interstellar space at a clip far exceeding either the Voyagers or the earlier Pioneer probes. Along with the variety of missions, cost estimates fluctuated wildly: the proposed Mars Geophysical Network came in only a little above the Pioneer cost cap, while others, like the behemoth Neptune-Triton System Mission, promised to break Cassini’s three billion dollar record and become the most expensive planetary mission in NASA’s history. With such a wide range of proposals, the most pressing question had become how to evaluate and rank so many missions.

Even as PSP^2 was considering how to manage the flood of proposals, MPL’s launch window was finally rolling around in October 2009, over half a year since VASE’s approval. Fitting for a mission that had fifteen years of design heritage behind it, it had experienced few difficulties in development, with comparatively smooth sailing on all fronts whether schedule or budgetary. Launch was equally smooth, though marked by a major first for the space program; instead of the traditional Deltas or Saturns, MPL was lifted into orbit by a Star Launch Thunderbolt, with a solid third stage attached to the spacecraft’s aeroshell completing the injection to a fast Mars-crossing trajectory that would reach the Red Planet in just six months instead of the usual eleven, so that MPL would reach the Martian north pole just as spring was turning into summer. The successful launch marked the first time that a NASA planetary science mission had ever been launched on a reusable vehicle, and a significant cost savings compared to more conventional vehicles. After launch, MPL settled into dormancy as it cruised towards Mars.

While one of the most recent Pioneer missions was nearing Mars, one of the oldest was finally reaching its destination after an epic, decade-long journey. Although reaching Encke had been time-consuming, the reward was sweet, as after multiple flybys of Venus and Earth to pump down the spacecraft’s orbital energy, Barnard became the second spacecraft in history to land on a comet in March of 2010, a month after reaching and putting itself into orbit around Encke. After a tense landing sequence, punctuated by a brief scare when it appeared that the mechanism designed to anchor the spacecraft to the comet had malfunctioned and Barnard had bounced back into orbit, it quickly set to work. Although the first images sent back from the lander showed jagged spires of relatively solid rock and other materials jutting ominously out of the comet’s surface, leading commentators to compare Encke to Mordor from J.R.R. Tolkien's Lord of the Rings books, further exploration over the next few weeks showed that this outwards appearance was only a surface illusion. Instead, most of the surface was covered in a thick, refractory layer of rocky dust, extending tens of centimeters into the comet and protecting its icier core from the harsh conditions of space, making the comet a kind of “icy dirtball,” as Helios-Encke some thirty years earlier had indicated. Barnard also built on Kirchhoff’s data on Tempel 2, showing that Encke-type comets also had little if any intrinsic magnetic field and an elevated level of “heavy hydrogen,” deuterium, compared to ordinary hydrogen, providing more evidence against the theory that cometary impacts had supplied most of the Earth’s water.

Just a month after Barnard touched down on Encke, MPL entered the atmosphere of Mars, streaking through nearly cloudless skies before safely descending to a landing point near the planet’s north pole. In a spectacular example of inter-agency cooperation, Japan’s Hayabusa[/] orbiter, which had only recently reached the planet itself, managed to successfully image the probe while it was descending under its parachute, the first time a spacecraft around another planet had recorded another, let alone while it was passing through the atmosphere. After this high note, MPL’s mission continued from success to success, with the probe’s robotic arm quickly revealing hoped-for evidence of water ice just under the Martian surface and the chemistry lab definitively confirming that perchlorates, believed to be responsible for Viking’s inconclusive biological results, were present in Martian soil. Although a blow to those few who hoped life might be present there, most scientists were pleased that this mystery had finally been definitively resolved, and focused more on the geological and climatological implications of MPL’s other data. MPL’s meteorological suite also provided important information on ground-level conditions near the Martian poles, complementing Viking and Mars Traverse Rover point data and orbital observations of the entire globe to help build refined atmospheric models, both of Mars and of Earth. After nearly six months of observations, MPL finally succumbed to dropping temperatures and dimming sunlight as Mars neared its autumnal equinox, shutting down for the final time in late September of 2010. Hayabusa observations of the site showed that dry ice formed around and over the probe that winter, as expected, and most likely destroyed MPL’s solar panels from having to support excessive, beyond-design weights. Between that and cold damage to the electronics, the spacecraft was permanently disabled, explaining why attempts to revive the spacecraft during the next Martian summer in summer of 2012 were unsuccessful.

Meanwhile, PSP^2 was nearing the completion of its final report after a long sequence of community outreach events, communications with NASA and other space agencies, and internal studies. Based on the scientific priorities it had drawn up with involvement from the wider planetary science community, the panel was generating a list of broad recommendations supplemented by a ranking of mission proposals according to cost and scientific value. Finally, after nearly two years of work, it published its draft final report in early 2011, prompting a final round of feedback before the publication of the final report that summer. As might have been expected after the Cornell Plan, it urged NASA in the strongest tones to launch at least one larger mission over the next decade and continue the Pioneer program with a cadence of one mission selection every other year, along with establishing an intermediate-cost program for missions like the Mars Geophysical Network or Venus Atmosphere Circulation Mission that were too large for Pioneer but, at least in the judgement of the committee, too small for a full-scale Cornerstone mission. Additionally, it recommended that NASA establish an ongoing technology development program rather than leaving it up to each individual mission to pay for whatever new instruments or technologies that it might need, and for NASA to seek more international partnerships with other space agencies. Finally, for the next Cornerstone mission the committee recommended that NASA immediately begin work on a Europa Orbiter mission, especially if further study could reduce the estimated price tag, followed by a Mars Sample Return campaign later in the decade.

Crucially for this recommendation, icy moons and Mars scientists had held the balance of power on PSP^2 and in the wider community; the United States had launched more missions to Mars than to any other planet or heavenly body aside from the Moon, and Galileo and Cassini’s missions to Jupiter and Saturn, respectively, had maintained a healthy community of scientists interested in Europa, Titan, Enceladus, Triton, and other, similar bodies. Compared to the relatively small and marginalized Venus or ice giants communities, icy moons and Mars had a large number of advocates able to push their case and develop mission concepts, while being simpler in a number of respects than missions to these other locations. Additionally, Mars and icy moons had built-in public relations advantages; Mars had been the destination for interplanetary spaceflight of any kind for over a century, while the icy moons, especially Europa, were widely regarded as the most likely place for alien life to exist in the solar system, both tempting attractions for the public and for planetary scientists. Although advocates of other destinations could make powerful arguments in their favor, they lacked the sheer magnetic draw of Mars or Europa as destinations, and had fallen behind in advocacy despite their best efforts. The result was a compromise between these two groups, based on the fact that the Europa Orbiter would be a cheaper and simpler mission than the multi-mission Mars Sample Return campaign JPL had envisioned since the 1980s. Combined with their recommendation of an active Pioneer program, which could easily support smaller Mars missions, Venus missions, and minor planets missions, and an intermediate category that could cover larger and gas giants missions, the final report had something for just about everyone in the planetary science community, thus preserving the unified voice that had led to the creation of PSP^2 in the first place.

While Congress had already approved and funded an ongoing frequent Pioneer program, the board’s other recommendations would require approval from the Hill, so that the publication of the report in early 2011 only marked the beginning of a new advocacy campaign. As they had in previous years, planetary scientists alternated pilgrimages to Washington with work in the lab focusing on addressing Congressional concerns with their recommendations. Despite the estimated cost of a Europa mission, Congress proved receptive to the idea of a new mission focused on Europa’s postulated under-ice sea, perhaps inspired by the idea of discovering alien life, though they had concerns over the cost. Despite being operationally simpler and having a projected cost less than Mars Sample Return, the Europa Orbiter was still expected to cost considerably more than Cassini, a result of the complex mission requirements, the difficulty of reaching Europa orbit, and the extremely harsh conditions of near-Jovian space, especially the radiation environment. Prompted by these Congressional concerns, interested scientists refined the mission concept, dredging up an idea from the early days of Europa mission planning in the 1990s to have a Jovian orbiter make many Europa flybys instead of actually putting itself into Europa orbit, thus reducing the amount of propellant needed and simplifying the mission. Moreover, by spending only brief periods of time deep inside the Jovian radiation belts instead of being forced to continually reside in them, the lifetime of the spacecraft could be greatly increased and it could perform some incidental science focused on the outer moons Ganymede and Callisto, and on Jupiter itself. NASA study of the concept also showed that this option’s impact on science would be minimal or, in some cases, actually positive compared with the orbiter option, while the cost of the mission could be slashed by more than half. With such positive results, Congress approved a new start on the Europa Systems Mission, or ESM, last year, with a Saturn Heavy launch planned to boost the probe towards Jupiter in 2019 or 2020.

In the meantime, however, other new recommendations by PSP^2 suffered. Despite the panel’s strong insistence on a new intermediate-class program to fill the gap between cheap Pioneer missions and expensive Cornerstones, Congress proved cool to the idea and it was dropped by advocates shortly after the report’s publication, as were the establishment of a stable technology development budget line and the creation of a budget line for supporting data archiving and release and facilitating the development of new planetary scientists. Even the projected Mars Sample Return mission suffered, with serious study work not beginning until after the approval of ESM in 2014, and no flight now expected until the mid-2020s at best, possibly slipping mission completion to the late 2020s or even the early 2030s at earliest, about when some of the more optimistic recent projections put humans on or around Mars.

On the other hand, the Pioneer program has continued from success to success; even as PSP^2’s final report was being published, the Pioneer selection board announced that it had chosen the Mars Ice Orbiter, or MIO, for launch in 2013. Building on the detection of ice at MPL’s landing site, MIO is designed to use a ground-penetrating radar system to detect ice all over the planet, expanding MPL’s observations towards a global inventory of Martian subsurface ice. Since its arrival last year, MIO has been aerobraking into its final observation orbit, which it is expected to reach in October. In the 2013 selection, the selection board opted to return to the minor planets by choosing the Comet Tour mission, a multi-flyby spacecraft utilizing electric propulsion to visit several cometary nuclei to compare them with Encke and Tempel 2 and build a broader baseline of cometary properties for comparative paleontological analysis. Data from 2010’s private NEOSearch spacecraft has been very useful for constructing a target list, and launch is scheduled for later this year. Most recently, this year’s selection broke the pattern of alternation between Mars and other targets that had been beginning to draw some criticism from planetary scientists, instead opting for the Aeneas mission to the Trojan asteroids. Clustered before and behind Jupiter in its orbital path, the Trojans are believed to be relatively volatile-rich remnants of the early solar system, and windows into our solar system’s past, so that Aeneas may shed important light on the formation of the gas giants and other outer system bodies.

Farther afield, planetary scientists are already gearing up for the next PSP^2 survey, expected to begin in 2019, and for the Mars Sample Return mission planned for the next decade. Recent MSR studies have shown a need for at least one precursor mission, given the large, sophisticated rover planned for use in gathering samples and the complexity of precision landing on Mars, so that support is growing for a large rover mission in the early 2020s, following the launch of ESM, while cost issues have led NASA to approach ESA, Roscosmos, and JAXA about cooperating on the sample return itself. The idea of creating an intermediate mission class has also returned, though as of yet it lacks significant Congressional support. Nevertheless, should their new process continue functioning, the future of planetary science looks brighter than it has in decades, with a steady stream of missions set to head skywards and explore new--or old--worlds.
It's alive, it's Alive ! :D

i wish we had this planetary exploration program in own timeline
I wonder that PSP^2 not proposed Ballons mission for Mars, Jupiter or Saturn.
the Galileo/Cassini stile mission for Europa Systems Mission has the advances that ESM can use it Radar to scann other jupiter moons
It Lives! :D

What really caught my attention was the use of a Commercial Launch Vehicle by NASA for an interplanetary mission, something I don't think has happened yet IOTL - could be wrong about that though. And one which kept the launch cost right down by having a reusable first stage, thus trimming the total mission cost a bit.
Another great post! So has mars ATL been totally bereft of rovers since the Mars Traverse Rovers mission? I'm wondering if mars planetary science is ahead or behind of OTL.....probably ahead?
It Lives! :D

What really caught my attention was the use of a Commercial Launch Vehicle by NASA for an interplanetary mission, something I don't think has happened yet IOTL - could be wrong about that though. And one which kept the launch cost right down by having a reusable first stage, thus trimming the total mission cost a bit.

What has SpaceX launch this year ?
there was something, but what ?
a yes the Deep Space Climate Observatory !

by the way
could NASA probe launch by ULA with Atlas IV also count as Commercial Launch Vehicle ?!
So glad this is back!

Signed up for this forum to just leave a word of thanks. This TL has been amazing to read, so thanks for all the time and effort that went into it.
It Lives! :D

What really caught my attention was the use of a Commercial Launch Vehicle by NASA for an interplanetary mission, something I don't think has happened yet IOTL - could be wrong about that though.

It actually has happened--Mars Observer was launched on a commercial Titan run by Martin Marietta. Of course, Mars Observer was also unsuccessful, as was commercial Titan, so it's not that well remembered, but that was a genuinely commercial launch.

Technically, also, every launch since sometime in the 1990s, if not earlier, was a "commercial" launch, even Shuttle, but that doesn't really count.

It's alive, it's Alive ! :D

i wish we had this planetary exploration program in own timeline
I wonder that PSP^2 not proposed Ballons mission for Mars, Jupiter or Saturn.
They have been studied, but for the latter two targets the development risks were considered too high, while for the former the utility seemed too low.

You can assume that pretty much anything that has been put up before Discovery/New Frontiers or the Decadal Surveys IOTL has been put up here (except obviously for things that would be pointless in light of previous missions).

the Galileo/Cassini stile mission for Europa Systems Mission has the advances that ESM can use it Radar to scann other jupiter moons
It's actually Europa Clipper...it might fly by Io once or twice and see Callisto and Ganymede on the way over, but it's pretty Europa-focused.
Another great post! So has mars ATL been totally bereft of rovers since the Mars Traverse Rovers mission? I'm wondering if mars planetary science is ahead or behind of OTL.....probably ahead?

Yes, there have not been any rovers since the Mars Traverse Rovers, which were essentially an equivalent to the Mars Exploration Rovers of OTL. The way the budget worked out, there wasn't really another good opportunity until about now for another rover. Initially Mars scientists wanted to go directly to a Mars Sample Return mission, but then they decided that it was still just a bit too risky to do that first, so they changed to just launching a large rover similar to Curiosity (a prototype for the caching rover that they want).

I would say that Mars science is in some ways ahead, in some ways behind where it is OTL. As I've mentioned before, the butterflies have caused ALH84001 to not be retrieved, so there's been much more emphasis on Mars as a geological body, on Mars simply as another planet instead of a well of life (although that's been weakened since the detection of methane on the planet). There have been a number of orbiters, some similar to ones that were launched in reality, so that part is fairly similar (though note from this post that there's not been an equivalent to 2001 Mars Odyssey until quite recently).
So glad this is back!

Signed up for this forum to just leave a word of thanks. This TL has been amazing to read, so thanks for all the time and effort that went into it.
Hello! Welcome to the board, and I'm glad you've enjoyed the timeline! I hope you (and everyone else) will enjoy these last updates over the next few months, and find them a suitable capstone to the timeline. :)
Morning all. A new post means a new image! I present to you the Barnard comet lander.

Side Note

For those who may not know, David S. Portree has resurrected his old WIRED blog, "Beyond Apollo" as an independent blog, "DSFP's Spaceflight History," doing much the same thing he was doing at WIRED - looking back at the byways and might-have-beens of the Gemini, Apollo and early Shuttle eras.

And last week, he took a look back at plans for the Skylab-Salyut project that never happened - hearkening back to the ASTP II mission of Post #18 in Eyes Turned Skywards, which was quite obviously based on those same plans.

What killed the project in our timeline? Portree: "New cooperation was hampered by U.S. domestic politics: the Administration of Gerald Ford felt unable to commit to a new international piloted flight ahead of the November 1976 presidential election." But I have to think that, with Shuttle development in full swing, the cost didn't help, either.

Part IV, Post 22: NASA after Orion and the Saturn-II
Eyes Turned Skywards, Part IV: Post #22

Although 2008's Orion 1 mission appeared to be just another in the series of American-led lunar landings that had spanned the last decade, under the surface it represented a significant advancement from the Artemis missions. The introduction of the new pressurized rover enabled the crew to complete several multi-day traverses, including a 66 kilometer circumnavigation of Shackleton crater which hosted Lunar Outpost Orion (informally known, among other names, as “Shackleton Base” or “the Shack”). Additionally, the flight saw the successful debut of the Russian Luna-Pe lunar logistics vehicle, proving that (at least for the moment) they had excised some of the demons haunting their unmanned program and demonstrating a path forward for more ambitious future missions. After the return of Orion 1's crew, mission controllers continued to monitor the outpost's system as training of Orion 2's astronauts stepped up, preparing for the day that they would make the first return to a lunar base in history. This second mission would build on the infrastructure already established at the Shackleton site, spending a full three months on the lunar surface at what was, inevitably, described by the press as the moon base. In the course of this extended stay, the crew were to expand the site survey already begun by Whitt’s Orion 1 crew, venturing on multi-day traverses to survey other polar craters’ geography and test for the presence of frozen volatiles such as those already identified within Shackleton. However, they would also make extensive use of the outpost’s biology and medical laboratory capability, using the mission’s extended duration (nearly as long as all of the original Artemis missions combined) to test the effects of longer stays in lunar gravity on the crew, for comparison for baseline data already collected on Spacelab and Freedom, and rat studies in the pseudo-gravity of Freedom’s centrifuge lab.

The experiment which attracted the most attention during the mission, though, was surely the “moon farm,” aimed at evaluating the growth of plants brought from Earth in a variety of lunar conditions, including Earth-sourced soil, treated lunar regolith, and a primitive hydroponic setup. After the crew’s arrival at Shackleton in March 2009, NASA public affairs encouraged educators to have their students “follow along” in classrooms back on Earth, comparing the growth of their own beans, herbs, and potatoes to those sprouting on the moon. While Edward Boxall had been the primary “outreach source” for Orion 1, Orion 2’s main face in the media was thus Mission Science Officer Hannah Parker. With proper treatment and enrichment with bacteria and biological media, the lunar regolith proved to be a viable growth medium for crops, and the crew’s pictures of digging early-sprouting potatoes and carrots from the beds would be seen almost as often as images of their record-breaking 5-day trip to Sverdrup and de Gerlache craters. Sadly, though, the astronauts wouldn’t get to taste either the fruits or vegetables of their labor, as the harvest was to be returned to Earth for nutritional and chemical analysis to ensure the suitability of future lunar crops for human consumption.

While the first two Orion missions were proving tremendously successful in terms of scientific return--particularly given that each actually cost less than an Artemis sortie mission--plans for the future of NASA exploration were more up for debate. Orion, after all, was intended as a short-term outpost, incapable of effectively supporting small crews for more than a few months at a time, nothing like the more extensive (and more self-sufficient) lunar outposts being studied by Oasis project teams. At the same time, Space Station Freedom was beginning to reach the end of its design life--the station had already had its lifespan extended to 2014 by planned replacement of batteries and onboard systems, but eventually NASA would need to replace both outposts. Additionally, the time since either Orion and (certainly) Freedom had been planned had seen major advances in the state of the art in spaceflight, and further changes seemed on the horizon. The completely expendable Saturn Multibody seemed outdated when compared with the flight-proven semi-reusable Thunderbolt, much less beside the Lockheed Starclipper and European Aquila two-stage fully reusable rockets under active development. The potential of capturing some of these commercial and technological benefits in any full-scale lunar outpost or replacement for Freedom was immense, and many within NASA viewed a new wide-ranging evaluation of the agency’s programs, vehicles, and goals to be necessary to maintain the agency’s leadership into the coming era of spaceflight. In 2009, as the Orion 2 crew worked on the ground at Shackleton, the newly re-elected President James Woods heeded these thoughts, directing Administrator Banks to conduct a broad-scope review of NASA’s capabilities and direction, and provide recommendations for a plan for the future, similar to the Richards-Davis Report from more than 15 year earlier.

The report began its evaluations with the fundamentals of the agency’s human spaceflight capabilities: Apollo and Saturn. For almost 50 years, pairings of these two families had served as NASA’s backbone, from the original Apollo program to Skylab, Spacelab to Freedom, and Artemis to Orion. However, Saturn Multibody--for all its flexibility and relatively low costs for an expendable rocket--was more than twenty years old, and even the “Interim Improvement Program” variant which lifted crews to Freedom and Orion dated to the Gore administration. Placed beside Thunderbolt’s reusability and low cost, the Saturn seemed exorbitantly expensive, and even since 2004 NASA had been considering a reusable replacement heavy lifter. The initial “Phase A” round of studies--small and cheap conceptual evaluations from a wide variety of contractors--had returned in 2006, and ranged from “simple” additions of reusable engine pods or flyback hardware to the existing Saturn core, to immense clean-sheet reusable first and second stages capable, like Saturn, of throwing more than 70 tons into Earth orbit. However, while the agency generally considered some sort of new, reusable launch vehicle critical to enabling a revamped exploration program continuing in LEO, on the Moon, or even beyond, the Phase A proposals ran into a profound case of “sticker shock.” Mindful of his boss’ budget-conscious ways, Banks had commenced Phase B studies in 2007, focusing more on cost-effective ways of implementing at least some level of reuse while retaining Saturn-class performance, striving for a compromise that would displease as few as possible, even if it wouldn’t perfectly satisfy anyone. Thus, when the Banks Report landed on the President’s desk in late 2009 for evaluation of options and development of a cohesive plan with Congress on the Agency’s future, it already came with a suggestion for the new backbone vehicle for the agency’s future: the Saturn II.

As its name suggested, the Saturn II was a continuation of the agency’s Saturn line, using the same 6.6m main tankage and clustered-core design as Saturn Multibody to reach the required levels of payload to launch new space stations and support the heavy and bulky payloads under study for Oasis. However, the vehicle would also change many details in pursuit of more cost-effective operations, starting literally from the ground up. When designers at Boeing had considered the addition of reusability to the Saturn Multibody family, they were faced by the problem of trading added weight--in both structure and reusability systems--against the system’s payload capacity--its reason to be. However, since reusability of at least the first stage was viewed as critical to ensuring Saturn II’s cost effectiveness, Boeing turned to new technologies in pursuit of a solution. Staged combustion kerosene engines had been something of a novelty in the United States since the technology had made its way out of Russia after the collapse of the Soviet Union, and the more-efficient, higher-performing engines had seen several focused development programs during the Gore and Richards administrations. To gain reusability without sacrificing capability, Boeing proposed to replace the venerable F-1 family of Saturn V, Saturn IC, and Saturn Multibody with a pair of staged combustion engines, the Rocketdyne RS-76, a US-developed engine incorporating the latest in American production methods and the secrets of Soviet engine technology. Two of these engines, each producing 4 MN of sea-level thrust, would be the basis of the new Saturn II core. The margin bought by their much-improved specific impulse provided the cushion for adding reuse to the vehicle.

This reuse system had been a point of debate, even within the Boeing design team, with some favoring addition of wings and jet turbines, as with the European Aquila system which became public in the same year Saturn II was proposed to NASA. However, the difficulty was that a tremendous increase in structural mass would be necessary to accommodate the loads that could be expected in two axes for vertical takeoff and horizontal powered flight and landing, particularly given the tightly-optimized low weight of the basic Saturn Multibody tanks. With the more efficient main engines, Boeing had proposed--and NASA had approved--an initial Saturn II configuration which would return to its launch site and land in the manner of the StarLaunch Thunderbolt, indeed even proposing to partner with Allen’s SLS on the development of the new core. However, one problem complicated this: the thrust of the new main engines. While this would enhance their ability to perform the initial “boost back” burn and slow the stage’s entry into the atmosphere, there was no chance of achieving sufficient throttle authority for a safe touchdown on these engines. Therefore, for final touchdown, Boeing proposed to use a simple pair of smaller gas-generator engines, filling gaps on the vehicle boat-tail. These engines would be easier to re-light mid-flight, and their lower thrust would make the vehicle not only capable of landing safely, but also of achieving a T/W of 1 during touchdown under minimum throttle, enabling a gentler touchdown than Thunderbolt. The weight added by these landing engines was to be partially compensated for by using them during ascent for all the vehicle’s pitch, roll, and yaw control, meaning that the main engines could be fixed in place--a savings in gimbal mass and complexity judged by Boeing’s engineers to be more effective than a massive clustering of smaller staged combustion main engines.

In operation, the Saturn II proposal would launch from the ground in either a single or triple-core configuration (support for solid rocket boosters was to be dropped, with the gap filled by the cheaper reusable liquid boosters). The second stage was to be either the S-IVB or the S-IVC of the Multibody with minimal updates, depending on the mission, given that the costs of developing a large reusable orbital stage had been judged prohibitive within NASA’s cramped budget. However, to further minimize the penalties to their new heavy’s capability, NASA would also invest in new infrastructure--a barge or sea platform capable of serving as a downrange landing site for high-capacity single core flights or for the center core of Saturn II Heavies. The result of this and the more efficient main propulsion was that in spite of the penalties of reuse, Saturn II would have similar capabilities of the vehicle it was replacing: 21 tons to low Earth orbit on a single core and 76 tons in a Heavy configuration with downrange recovery of the center core, but with almost half the cost per launch. For those who had hoped for a fully-reusable super-heavy, Saturn II looked like a half-hearted compromise next to graphics of Aquila, Starclipper, or proposed Thunderbolt reusable second stages. However, NASA’s budget could only stretch to cover so much new development, given the ongoing lunar and LEO outpost program, and Saturn II was an implementation of relatively-conservative technology well-proven by Thunderbolt L1 that would give enough of the benefits of reuse to answer NASA’s needs.

Those needs certainly did not end with the new launch vehicle--instead, Saturn II was to be just a part of using the existing human spaceflight budget more efficiently to cover a more expansive program. Just as Orion’s outpost design enabled exchanging 3-launch $1.5 billion annual sorties lasting two weeks with $1.2 billion 2-launch missions lasting several times as long, Bank’s suggestion was to exploit reusable launch vehicles to do even more with the budget of Freedom and Orion. In the immediate future, he envisioned three major tracks, addressing three exploration missions--a deliberate nod to the “Constellations of Exploration” of Woods’ most immediate Republican predecessor. In Earth orbit, the Bank Report called for a new space station to replace the aging Space Station Freedom’s scientific capabilities. This could consist of one or two large modules launched aboard Saturn II, creating a basic station core which could then be supplemented in an evolutionary fashion by rigid or expandable modules launched to provide increased power, laboratory, and habitat capacity as-justified by the intentions of NASA, international partner, or commercial firms. In addition, he proposed that NASA’s venerable Apollo be merely the contingency capacity for this station, with primary logistics (if possible even including crew) to be contracted out to US commercial operators or bartered to international partners. This would leave the station as little as half as costly to operate as Freedom, a savings which could be rolled into the Oasis expanded lunar outpost.

Here, too, Banks called for supplementing Saturn II-launched primary systems with commercial capacity, and drew on plans previously studied by NASA and--particularly--Northrop. The overall plan for a sustainable lunar outpost was for Saturn-launched payloads and descent stages to convey crews and large components to the surface by drawing on a commercial-fed network of Pegasus-derived, TransOrbital-style tugs. With a single Saturn II-H launch, an Apollo and descent stage could be placed into orbit, as with the crew launch in Artemis in Orion. Here, though, the Pegasus tug to boost them to EML-2 would already be waiting in Earth orbit, topped from NASA depots kept filled by a competitive propellant market. At EML-2, a smaller depot (a derivative of Northrop’s existing Centaur-based TransOrbital depot) would allow the Pegasus to partially refill and begin the transit to lunar orbit, acting as a partial “uncrasher” before leaving the crew to their mission to the surface and returning via the EML-2 depot to Earth for reuse. The end result would be dramatically improved payload to the lunar surface while at the same time reducing cost. This, in turn, would be used to stretch each crew rotation to six months, and launch two missions a year--transitioning the Orion outpost site to a permanent Oasis facility for the same annual budget. Because these two prongs of the Banks plan could be implemented by redirection and more efficient spending of NASA’s existing budget, achieving a lunar base and new space station could serve as a foundation for more if the agency’s budget saw expansion in the future.

Banks knew his boss well, and the notion of leaning on privatized routine launches to reduce public spending while enhancing capability was almost a rhyme with Woods’ more general philosophy about government. Though a tough sell in Congress, ultimately the plan found enough support to pass; those representing NASA-heavy districts saw none of the feared cuts to their constituents’ livelihoods, while budget hawks like the President could hardly complain--even if the plan didn’t cut NASA spending, it at least wouldn’t require increases. The plan also proved popular with the public, where the new station and “first permanent lunar base” briefly captured public attention. Contracts for the development of the new station core, the Pegasus tug and depot hardware, and the new Saturn II were issued, supervised by the staff at Marshall, while Johnson settled into defining programs for the commercial supply of supplies, propellant, and potentially even crew to the next-generation exploration system.

While NASA was in the reviewing its goals and determining the best mix of private and government launches to enable the nation’s spaceflight goals, other commercial applications were being explored based on the same reduced cost of access to space. In addition to these long-speculated applications, new, more novel avenues were being explored than second-generation LEO communications constellations and the wide variety of plans for space tourism that had been fermenting since Thunderbolt was introduced. Funded in part by private investors and in part by the NSO, NEOSearch (founded by, among others, Peggy Barnes, ex-NASA astronaut) has been among the most notable and most successful of these efforts, launching one spacecraft five years ago and currently planning a second.

It was intended as a partially-charity, partially-commercial endeavor to launch a small, half-meter infrared telescope into Earth orbit, dedicated entirely to the mission of scanning the sky for asteroids. NEOSearch estimated that a single telescope in low Earth orbit would be able to catalogue over 80% of so-called “potentially hazardous objects,” or PHOs, over a five-year mission duration, blowing past earlier ground-based efforts to detect threatening asteroids, while costing little more than similarly efficient ground-based systems. However, in the process they would also amass the most complete database of asteroid properties, including orbital parameters, sizes, and compositions, in history--exactly the data which would be required to tap these “flying mountains” for rare metals and volatiles in the asteroid mining which had long featured in science fiction. Just as operators like Thunderbolt and Starclipper were turning science fiction into science fact, NEOSearch planned to sell access to their database to several firms popping up which planned to begin such asteroid mining in order to pay back the investments--a combination of global protection and capitalist success. After several years of fundraising, NEOSearch was able to begin bending metal, culminating in a launch on a Thunderbolt in early 2010. Over the past five years, the NEOSearch One telescope has become by far the largest single contributor of new objects to the minor planet lists, although the latest public data set is still estimated to be several percentage points short of the 80% PHO target.

Nevertheless, the telescope is healthy and data collection and processing are ongoing, so it may make up that distance yet. In the meantime, analysis of the public data set has not revealed any actually hazardous objects, and although several startups have ponied up the cash needed to obtain detailed information, all of them seem some ways from launch. NEOSearch itself is studying how to improve detection of objects interior to Earth’s orbit, which comprise most of the undetected fraction of PHOs at this point, and which are difficult for a telescope on or near Earth to detect due to their proximity to the Sun. Currently published concepts include putting a telescope at the first Earth-Sun Lagrange point, ESL-1, which will marginally improve detection ability, and putting one in a substantially lower heliocentric orbit, similar to that of Venus, where detection ability would be greatly increased. Launch costs to that orbit would, however, be considerably higher, as would spacecraft temperatures, while communications would be slower and more expensive to achieve than in low orbit or even at ESL-1. So far, no choice between the two has been publicly announced.

While pioneers of science fiction and spaceflight from Clarke to Von Braun might have been amazed by such a privately-funded science and exploration mission--separate from any national space programs and with a business plan half-charity and half-market-speculation--the explosion in even smaller unaffiliated payloads was astounding even to those witnessing it. In the early years of spaceflight, superpowers had mustered massive efforts of miniaturization and launch vehicle development to launch payloads like Vanguard, Explorer, or Sputnik, weighing less than 100 kg and consisting of little more than tight packages of batteries, solar panels, and radio antennas. Since then, most payloads had become much larger, but at the same time, the computer age had seen the minimum size of such “simple” systems as the original space vehicles shrink, and occasional proposals had circulated for the creation of “microsats”--satellites with minimum levels of capability but which could be extremely low-mass and, as a result, be developed and launched extraordinarily cheaply. Around the turn of the millennium, this concept had once again been current, and a joint MIT-Stanford initiative had yielded the “SpriteSat” standard--a tiny cubic satellite with rigidly standardized exterior dimensions, mass properties, and interfaces. Using little more processing power than was available in the burgeoning PDA or “smartphone” market, these spritesats could be assembled cheaply by universities, clubs, or even private individuals, then launched on any flight which could accommodate several kilograms of ballast. The concept had a slow start, but had rapidly exploded after 2005, fed by increasingly cheap electronics, availability of modular kit solutions, and the dropping cost of launch associated with NASA initiatives and the StarLaunch Thunderbolt.

As spritesats proliferated, solutions to the form factor’s power, avionics, communications requirements became available “off-the-shelf” (in some cases incorporating modified versions of handheld “satphone” systems for basic communications and telemetry, or PDA or smartphone processors as onboard avionics), and some NASA and university groups began to experiment with the potential which could be crammed into such a small, modular platform, attempting to miniaturize scientific instruments, communications gear, and even propulsion to turn spritesats from simple tumbling boxes on slowly decaying LEO tractories into fully-functional science platforms, potentially capable of even leaving LEO behind. The result was a growing divide among users of the modular hardware between groups or individuals building simple “dumb” spritesats to simply have, for a brief time, the achievement of their own personal microsatellite and those pushing the bounds of the capabilities of the systems, some of whom began to talk about a new standard with larger mass and dimensional limits and correspondingly larger potential as scientific platforms that would still be able to exploit some of the advances already being made in spritesats.

Most emblematic of this second group was the 2010 release of two ion-equipped NASA spritesats from the Orion 3 expedition’s discarded Pegasus stage after the completion of the crew’s Earth departure burn and the stage’s separation from the stack. Using limited onboard navigation, the spritesats--arguably tiny probes--were maneuvered from their near-heliocentric initial orbits, letting their maneuvering and ground-based signal tracking probe weak stability bounds in the outermost reaches of cislunar space. If advocates of larger microsats managed to make progress, the limited “Skipper” 1 and 2 (named for their track across the ripple-like shapes of cislunar gravitational potential wells near L-1, L-2, L-4, and L-5) might be followed in the future by more ambitious cheap missions.

However, such ambitions for cost-effective missions weren’t just limited to small spacecraft. Building on their past legacy and their accomplishments with the private sector, NASA was able to launch renewed programs in both LEO and on the lunar surface, while meeting the President’s goals of only minimal changes in the agency’s budget. At the same time, the private sector was beginning to take its own steps in growing markets for Earth-focused space applications and beginning to look at space-focused programs. The potential of commercial and government cooperation was being proven again and again, on missions ranging from individual kilograms to hundreds of tons and with budgets spanning six orders of magnitude.
So NASA is opting for reuse of the 1st/Core stages to bring down the per-launch costs a la OTL SpaceX. Sounds about right to me given the simple budgetary realities they have. And closing the cycle? I think this would be the first time NASA's going to have a launch system with such an engine ITTL AFAIK.

And clearly things are pushing ahead of OTL by some distance ITTL, simply on account of having kept the means to do so quickly and easily way back in 1968. It, really does make you stop, and think about what might have been...

http://www.astronautix.com/engines/rs76.htm - By any chance is that the RS-76 in question being used for this new Saturn II?
Great update

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.