As a young boy of seven or eight, long before there were earth satellites, astronauts, voyages to the moon, space shuttles or space stations in real life, I became enthralled with the concept of human space flight. My enthusiasm was largely prompted by early SciFi films such as Destination Moon, Forbidden Planet, Rocket Ship X-M, Flash Gorden, Buck Rodgers etc. (my favorite space film of all time is Silent Running starring Bruce Dern, its emotional impact exceeding in my opinion even 2001: A Space Odessey. This flic is despised by many technology oriented SciFi fans because of its pro environment and perceived anti tech theme.*) I also “religiously” watched early space themed TV shows such as Captain Video and his Video Rangers (yes, at age nine I had an “official” ID attesting that I was a Video Ranger in good standing) and its west coast imitator Tom Corbet Space Cadet. I eagerly consumed juvenile science fiction novels and short stories too numerous to list but especially works by Robert Heinlein such as Rocket Ship Galileo , Red Planet, Farmer in the Sky and Starman Jones and Issac Asimov’s Foundation Trilogy as well as his Lucky Star series (written under a pseudonym). One of my favorite juvenile SciFi books even to this day despite a somewhat archaic style is When Worlds Collide written by Philip Wylie and Edwin Balmer. The volume I obtained at the local library also contained its thrilling sequel After Worlds Collide which totally captivated me.**
As early as the third grade I was writing short stories of space exploration complete with alien adversaries and friends, all written in the first person as if depicting actual adventures I had experienced. For a class project I even had my mother make me a “space suit ” and helmet (assembled from a cardboard box with radio antenae affixed to the top which actually were discarded TV “rabbit ears”), such construction under my strict and critical supervision since only I knew exactly how it must appear. I yearned to be an astronaut long before the term had been coined.
When the Soviet Union placed Sputnik, the first artificial satellite into Earth orbit and quickly therafter orbited a dog (poor Laika, the first casualty in human efforts to reach for the stars) I was excited beyond words that our species had made its first step into space but dismayed that America was lagging behind our Cold War enemies, even more so when several of the first American attempts to match this feat exploded on the rocket pad
America’s first attempt to place artificial satellite in Earth orbit results in catastrophic failure when Vanguard rocket explodes on launch pad.
(I remember well my class being herded by teachers with much excitement into a large TV room at school to watch the first Vanguard attempt to launch an American artificial satelite only to see the rocket burst into flames and disintergrate in a massive fireball to the total horror of us all. In shocked silence we were returned to our classrooms.***) My views, of course, have evolved from those simplistic days but my enthusiasm for human space travel has never wavered in the slightest.
By junior high school most of my private thoughts and fantasies that weren’t related to the opposite sex or baseball concerned space flight and particularly Mars. I recall in eighth grade each member of my general science class was assigned to make a verbal report to the class on an astronomy subject of our choosing. I was assigned as a partner a young lady whose name now escapes me but on whom I had something of a crush. Of course our presentation was on Mars. To my surprise she was as knowledgable on the subject as I was myself.
Immediately following our presentation, two female classmates gave a report on astrology. I was insensed, loudly proclaiming that it was superstition not science and certainly not astronomy. Apparently my protests became a bit too vociferous and I was sent to the principal’s office. A letter to my mother resulted with a threat of suspension if i did not apologize in writing. I resentfully wrote the notes to the two young ladies, to the teacher and, for reasons I still don’t understand, to my partner. The presenters on astrology received an “A” for their efforts; my partner also received an “A” but I received a “B-“. (So ended all hopes I had for a budding romance). (It was a valuable lesson on the merits of keeping some thoughts private, however, my opinion of astrology has not changed. I have always been secretly proud that at such a young age I had the courage to object to such a casual confusion of science and superstition.)
Saturn V rocket lifts Apollo mission bound for the Moon
Why I didn’t choose science as a career path is a long and involved story. I think in part I was dissuaded by the ridicule I received from family (“you are too old for such nonsense”) and friends for my interest in such things. My Dad would have loved it if I had followed in his footsteps to become an engineer but my mechanical ineptness led me to conclude that such was not for me. For unknown reasons my Dad held science, “pointy head” professors and scientists and particularly my interest in space in considerable disdain. (In his youth one of the most insulting things you could say about a person was that he was a “dreamer” which was the equivalent of a wastrel or bum. I guess he was rather disappointed in me). For years I didn’t even mention the ideas which occupied a great part my thoughts to anyone save a handful of acquaintances who were similarly obsessed.
View of Earth as Apollo VIII emerges from behind the Moon
The history of American efforts in manned spaceflight began with incredible highs with the nation entranced by unbelievable and unforgetable achievements including Alan Shepard’s initial suborbital flight and John Glenn as the first American in orbit (the fact that the Russians Yuri Gagarin and later Gherman Titov preceded him in this feat did not lesson the excitement at all). Later the first circumlunar voyage by Apollo VIII and the next year the first Moon landing and Moon walk bordered on the surreal. No one ever dreamed that we would see pictures of the Earth taken from a spacecraft as it emerged from behind the Moon (with the astronauts reading the creation myth from Genisis as a captivated planet watched) or that we would witness the first step of a human on another world on live TV. The first Moon landing drew the world together, despite worldly disputes and ongoing wars, as no other event had before (people from around the planet typically did not say that America landed on the moon; they said we landed there). Unfortunately, these incredible events shared by the nation and indeed by the entire world were soon followed by depressing lows as the public largely lost interest in space flight and political and financial considerations and an underlying anti science bias led the country to retreat from all sense of vision or accomplishment, perhaps endangering the very survival of our species in the process.
Neil Armstrong, first human to walk on the Moon
Of course, the question always arises as to why we should spend our national treasure on “that Buck Rodgers stuff ” (as my Dad use to say) when we have so many problems on Earth that require our attention (ironically my Dad wound up working for NASA for several years on Syncom, one of the early communications satellites and later, after he had retired from the C.I.A., he became a vocal advocate of Reagan’s “Star Wars” largely space based missle defense system.) The argument in favor of a vigorous space program have been made so many times and are so overwhelmingly pursasive (at least in my mind) that I will only list a few here:
1) funds spent on space exploration are spent on earth creating tens or hundreds of thousands of well paying jobs and encouraging our youth to consider science and engineering as a career choice;
2) investment in space related areas leads to research and technological development with widespread earthside applications that would not otherwise occur (much as war spurs innovation but without the carnage, injustice and suffering);
3) investing in space is a way of channeling the innate aggressiveness of our species from warfare to worthwhile, nonviolent goals and adventure that does not involve murdering our fellow man;
4) the intrinsic curiosty of our species demands that we learn as much as is possible about the universe we inhabit and thereby perhaps gaining some measure of insight into our place in it. Humans learn best by “hands on” direct experience;
5) the search for life and ultimately other intelligences and/ or civilizations is perhaps the most exciting quest that humans can undertake. Interacting with other life forms or, alternatively, concluding that we are alone in the universe will change us in ways we cannot now begin to predict;
6) moving our heavy industry into space may be the only way in the long term that we can both maintain a technologically advanced civilization while preserving the Earth’s unique and irreplacable environment
7) resources in space are plentiful and given the development of the technology to reach them, readily available. The time will come when humans everywhere will regard the exploitation of resouces on our home planet as an abomination, a mindless and unnecessary rape of what should be maintained as a garden, not converted into a cesspool by its exploitation;
8) human space flight is cool. Unmanned scientific space probes are also important and may result in profound leaps in our collective knowlege but will never have the excitement or public interest of manned space adventures;
9) Long term human survival demands that we become an interplanetary and eventually interstellar species. As long as we have all our eggs in one basket, we are extremely vulnerable to sudden and unexpected extinction. The possible means of that extinction are unpredictable but extensive including the following:
a) war involving thermonuclear bombs or other weapons of mass destruction;
b) ecological collapse resulting from our inability to be good stewards of our beautiful planet;
c) impacts from planetary debis; somewhere out there, there is an asteroid or comet with Earth’s name on it. It is not a question of if but only of when a civilization ending or even extinction level impact will occur. Whether that happens tomorrow or ten thousand years or more from now, astronomers are in universal agreement that some day it will occur;
d) uncontrolled technology whether it results from genetic manipulations and experiments, artificial intelligence which surpasses our own and deems us unnecessary (hundreds of scientists and computer innovators including Stephen Hawkin, Elon Musk and Bill Gates have recently publically stated that they believe this is a serious and imminent concen; Musk has stated that the danger could be as little as five years away.), released nanoparticles which systematically destroy our enviornment, natural or accidentally induced volcanic action and earthquakes on a massive scale, Mathusian effects resuting from overpopulation which finally exceed the ability of new agricultural methods to keep pace, political and/or economic collapse (which after the events of 2008 seem far more likely than once believed), the collapse of our technological infrastructure which has become more and more vulnerable even as it has become more complicated, or some other world wide disaster that we have not yet forseen.
10). without seeking to turn our dreams into reality our existence becomes meaningless and our activities objectively and subjectively worthless.
Apollo Command and Service Modules in Lunar orbit
Lunar Excursion Module prepares for touchdown on Lunar surface
Nixon’s cancelation of the Apollo lunar program with three additional missions ready to go (and its hardware mostly discarded and junked, wasting billions of dollars, destroying countless careers and dispiriting much of the scientific community) dismayed me beyond words. The disaster which became the Space Shuttle at first gave me renewed hope of a viable space program. Indeed it was a marvelous looking machine but it quickly became obvious that compromises in its design which we later learned were primerly caused by military demands that it’s cargo bay be large enough to transport huge spy satellites as well as technology choices guided primerly by finances rather than an objective evaluation of alternatives and ultimate goals ensured that the Shuttle would never live up to its advertised purpose of frequent, safe and affordable access to near Earth space.The tragedies that subsequently occurred were almost as predictable as they were sad. It seemed that America’s infatuation with space exploration except for military purposes was over.
Space Shuttle during lift off
Space Shuttle in Earth orbit
Even the International Space Station (ISS), a complex and politically inspired mishmash of technologies of half a dozen nations which swallowed NASA’s budget for a decade or more with marginal scientific purpose was actually a backward step from early and far more simpile and inexpensive space station efforts such as Skylab. With the retirement of the Shuttle in part because of the realization that further disasters were probable, the U.S. has been compelled to hitchhike with the Russians to have access to the huge financial and political investment we had made in the creation of the ISS, a humbling situation to put it mildly which persists to the current day. Even more dismaying, the International Space Station is totally irrelavent to either establishing a Moon colony or for a mission to Mars and attempts to justify its existence by requiring its use for such missions only makes such ventures more complex, outrageously expensive and functionally impractical.
International Space Station
I have long noted that most written discourses on where we should go from here with a viable space program either emphasize alternative and seemingly mutually exclusive destinations (the Moon, nearby asteroids, Mars etc) or discuss proposed or actual hardware (Orion, various craft in development by private companies such as SpaceX, Boeing etc) or debate whether robotic craft should be emphasized over more expensive and risky human flights. There is little discussion of what capabilities are needed to actually transform mankind into a interplanatary species. In my view before technologies are adopted we should examine in some detail what would be required to satisfy long term space related goals for the remainder of this century.This must be done before any rational decision can be made as to which technology should be pursued.
Chemical rockets have served us well in making the initial small steps beyond our home world but their time is quickly passing despite ongoing programs by NASA, SpaceX and others to develope huge new chemical rockets in support of uncertain future space program goals. Such efforts may be useful in the short term and may be used to orbit materials for assembly of the craft in space which will really open the solar system to human exploitation but they essentially will only return us to the launch capabilities of the early 1970s.
Current chemical rockets have thrust may times 1g (one “g” of thrust is equal to the gravity experienced on the surface of the Earth) with acceleration at 5gs or higher being commonplace but such thrust can only be sustained by chemical rockets for a matter of minutes. Chemical rocket technology was marginal even for manned Moon flights requiring multiple stages and complex flight arangements. Indeed the argument has been made that the entire Apollo program was an anomoly brought on by Cold War competition before technology really had advanced to the point that the effort was reasonable. Of course, this makes its success all the more remarkable.
The specific impulse (a measure of the efficiency of a rocket engine) of these awesome but dangerously complex chemical rockets is small compared to alternatives that should soon be available and we are approaching the absolute limits of their capabilities. For exploration beyond our own moon chemical rockets are problematic at best although in one version of NASA’s proposed manned Mars exploration contingency plans chemical rockets are used with perhaps a small nuclear reactor for onboard power requirements. NASA indicates that the entire trip would take over 600 days (another study envisions a trip with total mission time of four years). The mission would use the new NASA heavy lift rocket currently under development and might include a flyby of Venus as well as Mars with no landing. Assuming the political decision is made to proceed (a doubtful assumption at best) this mission would take place in 2025 if only a flyby was intended or in the mid to late 2030s at the earliest if an actual Mars landing is planned. Other NASA projected dates for a Martian landing suggest it may not occur until well into the 2060s (hopefully, Chinese, Russian, Indian and even European explorers will welcome the American astronauts when they belatedly arrive).
The NASA proposal for a flyby is risky. From the point of view of the radiation to which astronauts would be exposed, the difficulty of maintaining equipment in a hostile enviornment for such an extensive period, the effect of prolonged weightlessness on astronauts, the size of the space vehicle and the vast amount of chemical fuel required, not to mention the impact on physical and mental endurance of the astronauts, in my view this proposal of a 600 day mission is unlikely to be successful (the four year proposal is absurd and will never happen). There are solutions to most of these problems but they involve additional technological risk. We could use modern day astronaut heros to inspire our unconcened and aimless youth but I don’t think any of us desire dead heros or failed missions which end in catastrophe.
Equally challenging are various plans by private concerns for Mars missions using chemical rockets. Indeed there are so many proposals for non government manned Mars expeditions with constantly changing parameters it is a challenge to determine which are serious and which are pipe dreams.
a) One such plan (“Inspiration Mars” ) would be a circumnavigation or flyby of Mars by a “couple, preferably married” without a landing much as Apollo VIII did with the moon in 1968 but with a one way trip time to Mars of at least seven months and total voyage time of slightly over five hundred days. This mission allegedly is planned to be launched in January of 2018 and arrive in the vincinity of Mars in August thereby beating NASA’s similar proposed mission by seven years.
b) Other plans would be one way trips with the crew permanently staying on Mars and being resupplied periodically with materials and additional colonists (“Mars to Stay” and “Mars Direct”) or multiple Mars vessels containing two astronauts each which would offer a continuing resupply, rescue and replacement capability.
c) Another proposal (“Mars One”) suggests landing four persons on Mars in 2025 (the entire mission to be broadcast to Earth in a unique edition of reality TV) with an additional four adventurers to arrive every two years with a total number of colonists expected to be twenty by 2033. One critique of this plan estimates each colonist’s life expectancy, assuming they arrive safely on the surface of Mars at all, to be sixty-eight days and others have called the plan fanancially bogus, fanciful, scientifically irresponsible and suicidal. Even this assessment presumes the proposal isn’t a scam as some suspect. Despite this and frank statements by the organizers that the colonists would never return to Earth, there reportedly have been over 200,000 volunteers (the accuracy of this figure has been disputed) for this one way mission.
d) Elon Musk of PayPal, Tesla and SpaceX fame has proposed a settlement of 80,000 vegetarians (Don’t ask. Even billionaire visionaries have their quirks) in a permanent Mars colony to be established beginning in the mid 2020s with the Martian colonists largely surviving by using natural resources available on Mars.
These proposed missions, although very exciting, even thrilling for advocates of space exploration and colonization, have a high probability for disaster if they actually are attempted at all. The concern is that should these missions fail with the resultant loss of life it may significantly set back or even cause the cancellation of more robust Martian manned mission plans.
On the other hand, should any of these missions be successful, it probably would greatly encourage further exploration efforts. Waiting for NASA and U.S. policy to determine such ventures to be viable and in the national interest has not been fruitful since the last Lunar landing in 1972. Many have concluded that such missions may never occur if the decision to proceed is left to the politicians or to NASA and that, accordingly, the inherent risks of these proposed missions are justified. Of the nongovernmental plans, “Mars Direct” (which would largely utilize existing or developing hardware and would forsee a far more economical mission) seems the most practical but it would rely on boosters and spacecraft under development by NASA or perhaps by SpaceX. Since both have their own ideas of how to proceed with the space program and seem jealous of alternatives, it is difficult to see how this plan will proceed. The most optimistic senario would be a colaboration between SpaceX and the Mars Society which has proposed the Mars Direct Plan. Of significant concern for private sourced Mars exploration is the recent statement by NASA’s Director in response to a Congressional suggestion that NASA and private concerns should compete to be first to Mars. He reponded that no private firm will reach Mars. This may be fairly interpreted to mean that NASA will not allow it to happen and has the political connections to enforce this determination.
NASA seems intent on awaiting the ideal and mature technology before attempting a Mars mission. This would be like Columbus waiting for a modern cruise ship before commencing his voyage. With each election redirecting (pun intended) the NASA effort, it may be that we must either endorse a nongovernmental effort or accept that such missions will be attempted by other nations if they occur at all.
The innate limitations of chemical rockets has led NASA and others to consider alternatives for interplanetary exploration including VASMIR and other electromagnetic based drives, small fission reactors (an area of intense Russian research), compact fusion and even antimatter.
Irrespective of its power source, the ideal spacecraft for exploration and colonization of the solar system as well as interstellar exploration (assuming no way is ever found to bypass the speed of light limitation ) would be capable of sustained acceleration of 1g or 32 feet per second per second. Assuming the ability to maintain such acceleration until half way to the destination, then decelerating at 1g for the second half of the journey, the implications are breathtaking. The ability to accelerate at such a level has the advantage that Hohmann transfer orbits can be avoided, greatly shortening the distance to be traveled and giving significant flexibility not possible with the minimum thrust levels currently utilized in all manned and robotic interplanetary craft. With such acceleration you would simply aim at the point your destination will be at the time of arrival without consideration of resticting orbital mechanics. A continuous 1g acceleration has a side benefit of maintaining normal gravity for the astronauts throughout the voyage, avoiding the difficult choice between an extremely complicated apparatus to simulate gravity or deterioration of the astronauts’ musculature, skeleton and immune systems caused by prolonged exposure to a zero or micro g enviornment.
For a hypothetical Mars mission we will assume an average distance from Earth of 100 million miles. At closest approach (at opposition) Mars occasionally comes to within 35 million miles of Earth (and at opposition will approach this distance in 2018) but this is rare because of Mars’ highly eccentric ellipsical orbit. More commonly the closest approach distance between Mars and Earth is between 45 and 60 million miles. Even this only occurs every 26 months. Our utilization of 100 million miles in our calculations assumes that we would not always want to await the closest approach and takes into consideration that both Earth and Mars would continue in their orbits during the voyage making the distance between them to undergo continuous change.
An acceleration of 1g for one day results in a speed relative to Earth (delta V or change in velocity) of around 500 miles per second or perhaps 43 million miles per day. After accelerating for a day and coasting for about thirty-two hours or so and then decelerating for another day the spacecraft would arrive in the vicinity of Mars with a total elapsed travel time of around 3 1/3 days (Travel time would be around 2 1/2 days if 1g acceleration was sustained to the halfway point). Compare this with the NASA proposed 600 day mission of which up to nine months would be spent enroute. Amazing!!!
Mars seen with realistic coloration
When Mars and Earth are farthest apart the distance between them is approximently 240 million miles. Presuming a travel distance of 300 million miles (since the intervening sun would inconveniently restrict a more direct route) and 1g acceleration for one day and deceleration for a like period, the one way travel time from Earth to Mars would be just eight days.
Similar calculations for a trip to Jupiter with acceleration at 1g for one day and a similar one day deceleration at the end of the journey (assuming a one way mean distance of 700 million miles) results in a one way travel time of just over 17 days. If the spacecraft for our hypothetical Jupiter mission could accelerate at 1g for two days and decelerate at the same rate for the final two days (perhaps refueling in Jupiter orbit or on one of its moons for the return trip) the travel time to Jupiter is reduced to slightly over eleven days.
For interstellar missions, acceleration at 1g for a period of a about one year results in a speed of .95c (95 per cent of the speed of light) (this calculation of velocity does not take into consideration relativistic effects. When relativity is factored in, the time to attain a speed of .95c is actually slightly more than a year from the perspective of an Earthbound “observer.”) With deceleration at 1g also for a bit more than a year the total travel time to Alpha Centauri ( a 4.37 light year distance) would be approximately 5 1/2 years from an Earth based measurement of time. Significantly less than this time would transpire from the perspective of the spacecraft crew because of time dialation effects: at .95 C the spacecraft crew would experience a little less than one year for every three years experienced on Earth, however, during aceleration and deceleration the average time dialation factor would be small. Accordingly, the total voyage time experience by the crew would be around three and a half years: see Einstein’s Special Theory of Relativity. The formula for determining time dialation effects of relativistic velocities is
t =T/ (1-v²/c²)½
where t = time observed on the spacecraft, T= time observed on Earth, v=the speed of the moving craft relative to Earth, and c= the speed of light in a vacuum. Simple calculations demonstrate that the dialation effect is for all practical purposes negligible until a velocity that exceeds .6c or so is attained and becomes truly remarkable above .9c.
Interestingly for those contemplating voyages to stars more distant than Alpha Centauri is that the measurement of voyage time from an earthbound perspective given the ability to accelerate at 1g for a period of a little more than a year or so and decelerate for a like period is always around a year longer than the distance traveled measured in light years (except for extremely long voyages of hundreds of light years or more) , i.e. a bit over 11 years to travel 10 light years, a bit over 21 years to travel 20 light years etc. From an earthbound perspective, acceleration at 1g for longer than a one year period does not reduce travel time in any significant way (accelerating at 1g for two years only increases velocity of the spacecraft to .99c) although again due to time dialation effects the travel time from the spacecraft crew’s perpective could be substantially reduced by continuous acceleration. (At .99c seven years would pass on Earth for every year that is experienced by the crew; at .9999c, which would require five years of acceleration at 1g, 70 years would pass on Earth for every year experienced by the crew). Indeed from the crew’s perspective the center of the Galaxy, a distance of thousands of light years, could easily be reached within a single lifetime if continuous 1g acceleration becomes feasible even though thousands of years would have elapsed on Earth during such a monumental journey.
Artists impression exoplanet: credit ESO
Certainly problems exist for any interstelar mission which is able to attain a significant per centage of the speed of light, such as the danger of encountering even a dust sized particle at such speeds (which would be catastrophic with an energy release in the order of magnitude of a large nuclear explosion) as well as experiencing unique and potentially deadly radiation generated by such speeds, but these are simply issues future technology will need to address, not game stoppers in themselves (theoretical scientists have already proposed several possible solutions to these problems). If the means is found for continuous 1g acceleration, a significant challenge to put it mildly, doubtlessly these issues will be resolved.
We currently have no technology which would permit 1g acceleration for a day much less a year or more. Continuous acceleration at 1g for periods of one year is inconceivable with any technology currently envisioned (well, excluding the emdrive/Cannae drive which in theory might make such accelerations possible but whose feasibility or even existence has not yet been confirmed despite promising experimental studies by NASA and the Chinese. NASA Eagleworks’ experiments with the ultimate goal of developing a warp drive which might enable high sub light speeds almost instantaneouly in addition to opening the possibility of faster than light travel are even more speculative. See my previous blog: Random thoughts: Perpetual motion, Dean Drive, cold fusion, the em (Q)drive and warp drive.)
Dr. Harold White of NASA’s Eagleworks and artist Mark Rademaker created this rendition of a future (and perhaps fanciful) warp drive spacecraft that might be capable of high sub light and even effective FTL “speeds” which in theory might permit voyages to Alpha Centauri in two weeks.
On the other hand, 1g acceleration for the four days needed for nearly ideal interplanetary voyages to Mars and other destinations in the inner Solar System ( i.e. 1g acceleration for a day followed by 1g deceleration for an additional day each way for a round trip voyage) may become possible with technology that will be available within the next 25 to 30 years ( perhaps using a combination of fusion technology and a Vasmir electromagnetic drive system). The day when routine and rapid access to the inner planets is commonplace is approaching but we will have to wait awhile longer for the technology to arrive.
Rendition of proposed fusion drive spacecraft under development by MSNW LLC and the University of Washington. Craft utilizes solar array for auxilliary power and/or ignition.
It is likely, however, that we will have the technology to build a somewhat primitive fusion drive capable of .16 g acceleration continuously for two days within the next decade or so. (The Russians appear to be taking a different approach, using small fission reactors instead of fusion and may achieve a similar operational capability within a comparable time frame.) As an alternative depending on technology issues, a significantly lower acceleration, slightly over .07g, for a longer period, say eight days (which at least one report to NASA suggests is the optimal period of acceleration for fusion drives currently under development), or continuous burns at even somewhat lower g levels might work almost as well. Of course four “burns” would be required for a round trip voyage which also seems attainable within ten years or so. (note: gravitational effects of the sun, approximately .06g, would significantly effect these calculations and although the overall effect on the round trip would be negligible with accelerations of 1g, it becomes increasingly more significant at lower accelerations and would require a higher acceleration than a direct calculation would suggest). For clarity, the below calculations are simplified but are fairly accurate.
After two days the Mars bound spacecraft accelerating at .16g (factoring in the sun’s negative .06g gravitational effect on the outward Mars bound journey for a net effective acceleration of .1g) would have attained a velocity of 100 miles per second or 8.6 million miles per day. For Mars exploration this is more than satisfactory. For the 100 million mile Mars voyage hypothetically discussed above this results in a one way travel time to Mars of two weeks. A mission of 30 days which includes perhaps two days in Mars orbit (or on the Martian surface) thereby becomes feasible in the near future.
On the other hand, an acceleration of .07 g (again factoring in the sun’s negative gravitational effects for the outward Mars bound journey for a net effective acceleration of .01g) for eight days (with deceleration at approximately the same net rate and duration) results in a one way travel time to Mars of thirty-eight days allowing a mission of 90 days including two weeks in Mars orbit (or on the Martian surface).
NASA has studied both 30 day and 90 day roundtrip Mars missions using anticipated fusion technology. Even utilizing the most conservative estimates of the efficiency of fusion drives under development, the studies conclude that both missions should be feasible within the forseeable future (with a goal for the mission to be accomplished in the mid to late 2030s). While the technology for such a mission may become available before the mid 2030s, it is doubtful that the political will to proceed will exist before then absent the prior establishment of colonies on the Moon or voyages to Mars by the Chineese and/or Russians.The fact that a huge investment will have been made in NASA’s heavy lift chemical rocket may also discourage a sudden switch to a more capable spacecraft.
The primary difference between a 30 day mission and a 90 day mission in the NASA study of fusion powered Mars missions is the portion of the spacecraft which will be payload rather than fuel. It is estimated that for a 90 day expedition as much as 70% of the beginning mass of the spacecraft could be payload while for a 30 day voyage only about 30% to 35% would be available for payload. (Both of these estimates far exceed todays chemical rockets in which only a miniscule fraction of the start weight is payload.) The longer 90 day trip would allow a larger payload because of smaller fuel requirements but some of this additional mass available would be utilized because of significantly higher requirements for expendibles such as oxygen, water and other provisions as well as signifiicant additional weight for radiation shielding needed because of the longer exposure times in space. For these and other reasons, the 30 day mission seems very attractive.
There also have been studies of a nine month Mars mission using a less capable fusion drive or perhaps a Vasmir or other electromagnetic drive utilizing solar and/or a compact fission plant for power. Although this is certainly better than the 600 day proposal, it still would place an enormous strain on both crew and equipment. It is likely this alternative for the initial Mars landing expedition will be selected only if technological or financial considerations make a more rebust spacecraft unfeasible at the time the mission decisions are made.
So that is what we need to again have an exciting space program and perhaps guarantee the survival of our species in the process. How do we get there?
First, we must understand that publicity of the new Orion spacecraft currently under development by NASA is somewhat confusing and disconcerting to put it mildly. “Orion” is a puzzling name adopted by NASA for this latest space program. A prior research project of the 1960s dubbed “Project Orion,” totally unconnected to the current effort of the same name, would have used external nuclear pulse propulsion, i.e. thousands of nuclear bombs ranging in size from .1 kiloton to a hundred kilotons or more which would be exploded behind a pusher plate to attain interplanetary capability. Indeed, studies indicated this proposal had the capability to send a crew of two hundred on a four week roundtrip mission to Mars and theoretically had the capability for a “slow” interstellar mission.
Original Project Orion proposal powered by thousands of external nuclear blasts
Surprisingly, this was actually technologically feasible even in the 1960s but totally terrifying despite Carl Sagan’s somewhat whimsical comment that it would be a marvelous way to be rid of the massive nuclear arsenal we had accumulated. Yes, during the Cold War insanity seemed to reach even scientific ranks. The 1963 Partial Nuclear Test Ban Treaty put an end to research and development of this rather bizarre idea).
Current Orion crew capsule under development
The current Orion, a somewhat larger and more technically advanced version of the Apollo Command Module (and on casual examination looking very similar to it), although originally descibed as a Mars vehicle before Obama changed NASA’s short term priorities, by itself could never be used for a Mars landing mission although a circumnavigational loop around the moon copying the 1968 Apollo VIII mission or even a similar mission around Mars is possible. Its proposed use to reach and “redirect” a nearby asteroid is interesting but actually the idea is probably a politically motivated evasion based on the decision to abandon any thought of returning to the Moon in the near future**** because of funding considerations while still maintaining a program which has financial tentacles firmly entrenched in dozens of Congressional districts. Recently, NASA modified even this modest idea to dislodging a 12 foot long chunk of an astroid and redirecting this to lunar orbit, justifying this absurd venture as a means of testing ion drives which just as easily could be tested in earth or lunar orbit. It is a sad politically inspired joke but no one is laughing). (One view suggests any space program is better than none at all, but this idea is all but useless except as a spur for enabling technology. Better to have the funds invested in more advanced technologies than wasted on this boondoggle). As for using it for a Mars expedition, imagine two or four astronauts confined in such a craft not much larger than a large bathroom for more than 600 days during a mission using chemical rockets. Seemingly impractical and perhaps suicidal (or homicidal lol).
Recently there has been mention in NASA circles of one or more Orions docking with a crew habitation module for a future Mars expedition. For reasons discussed above, this also is risky using chemical rockets. Although NASA has not yet officially announced how a Mars mission might be accomplished, it is clear that their funding of research on more exotic propulsion methods, including Vasmir, small fission reactors and fusion, is aimed at the development of more capable transportation systems with the Orion hopefully being little more than a means to reach the actual Mars craft, perhaps some version of the Nautilus X proposal, the Orion serving as a lifeboat in case of trouble during the voyage, perhaps venturing to the two small moons of Mars after attaining Mars orbit and used to land the crew back on Earth once the larger craft returns to Earth orbit. It could not even be used to land on Mars after arrival in Mars orbit. Under this senario, the actual Mars spacecraft, perhaps including landing craft, presumably would be assembled in Earth orbit much as was done with the ISS. At least this seems a reasonable alternative that would utilize the investment in Orion without attempting to use it as a habitation module for an overly ambitious 600 day mission.
Nautilus X proposal
As reported in previous blogs the Lockheed-Martin Skunk Works announced last year that it is working on a 100 megawat compact fusion reactor and expected to have a prototype within five years and a production model suitable for military and other government uses within a decade. If accomplished within this time frame it is likely Lockheed-Martin, which specializes in high performance aircraft and rockets, will quickly develope a version suitable for space flight. A competitor, Helion Fusion has under development a fusion reactor and have announced they expect to have a 50 megawatt prototype in operation by 2019. This company is a sister to MSNW LLC which is investigating fusion power for space drive applications. Both companies arose as a result of fusion research conducted at the University of Washington and have noted fusion researcher Professor John Slough as a prime contributor/founder.
Interestingly, Boeing, a competitor and sometimes collaborator with Lockheed-Martin on various space ventures, recently announced the relocation of a dozen of its scientific/engineering staff to the University of Washington where a new joint research laboratory for aircraft and spacecraft manufacturing and assembly has been created. It is believed that Boeing is also active in fusion research with emphasis on spacecraft applications although perhaps trailing Lockheed-Martin in the race to produce a production model of a compact fusion reactor. While the new joint lab does not appear to be directly connected to fusion research, it streaches credibility to believe their relocation to the University of Washington where cutting edge fusion research is taking place is only a coincidence. If it does suggest collaboration between Boeing, Helion and MSMW and perhaps an infusion of needed funding, it may be that we will see progress in fusion development even more quickly than the Lockheed-Martin announcement suggests. At this point the only real question is whether the U.S. will muster the political will to make this a reality or whether vested interests (read Big Oil) will successfully supress a technology that could be a game changer not only in our space exploration efforts but in satisfying our earth bound clean energy needs as well.
I am a little pessimistic concerning the current political realities in part because of our history of abandoning goals after considerable time, effort, and treasure has been invested into space related ventures. A failure of one of the more ambitious missions, especially if there is a loss of life, would likely be used by those in opposition to manned space flight as a justification for cancelling funding for such efforts.
Many, including scientists engaged in diverse areas of research, reject manned space flight as a worthwhile goal, urging the funds to be placed in other research areas. The assumption that they are competeing for the same research funds is highly unrealistic, even naive, but purvasive in the scientific community.There is little understanding that only if the public again gets excited about science will funding in all areas of research surge. Others assert that government funds should not be used for such purposes when we have unmet needs on Earth and/or that the alternative of additional tax cuts would be far more popular with taxpayers even though our nonmilitary space budget has been less than 1% of the total federal budget every year since 1975. Compare this to the total military budget which is typically 16 to 20% of the federal budget. In 2015 NASA is budgeted to receive $18.5 billion out of a total federal budget of $4 trillion, the NASA budget totalling slightly over one-half of one percent of the Federal budget, while the Depatment of Defense is technically budgeted for $585 billion but with actual overall defense and national security expendisures close to $1 trillion. With the gross national product of the U.S. being around $18 trillion, the portion of the total economy invested in government funded civilian space activities is one dollar in a thousand, hardly an excessive amount for an activity that is hugely important to the economy and crucial for long term human survival.
In an ideal world the NASA budget would be at least doubled which would still only bring its total budget to around 1% of the total Federal budget (for comparison, during the Apollo Moon landing program NASA’s budget reached 4 1/2% of the total Federal budget. We can only imagine what might be accomplished with such funding today). In the real world this is unlikely to occur anytime soon; however, if the NASA budget was increased by 25% to 30% with incremental annual budget increases thereafter many opportunities would open. My recommendation would be that we abandon our support of the ISS, an unnessesary drain on NASA’s budget with marginal purpose or benefits (initially it existed primerily to provide a destination for the Space Shuttle but the Shuttle no longer is operational), that the asteroid redirect program be cancelled (and villified as politically inspired nonsense) and that we concentrate our efforts on establishment of a Lunar colony by 2025 while simultaneously funding an aggressive Mars mission with the goal of also establishing a permanent Martian colony by 2035 (if a short term choice between the two goals becomes necessary because of funding considerations I would favor the Mars colony which has the promise of becoming self sustaining within a reasonable period as well as showing significant results, one way or the other, in our search for extra terrestrial life). (Termination of the SLS heavy lift booster does not seem practical or politically possible at this point and indeed such termination might cause the cancellation of virtually all manned progams. Accordingly, it should be continued despite the huge waste of treasure and effort it has entailed). NASA wastes billions on programs which scarcely match the technology of the late 1960s while offering pittances to advanced research which have promise but little political support. As long as this situation continues it is difficult to see how the space program will advance beyond its current snails pace.
With such additional funding and redirection of effort and resources, realistic funding should also be available for long term research and development of advanced technologies including fusion drives and, should further investigation justify it, Q Drive (EM Drive and/or Cannae Drive) and warp drive research. We should not, however, await the development of ideal technologies before proceeding since there will always be the prospect of something better in the future which would in effect mean forever turning our backs on space missions which can be accomplished now.
It may be that reliance on NASA for future American space efforts is misplaced since as a governmental agency it will always be subject to political forces. If this is true, our last hope for a viable space prgram may lie in the private sector with companies such as SpaceX but until these companies develope independent funding sources they remain little more than contractors for NASA and are subject to the same political forces. If various proposals, such as hotels in space, mining asteroids etc. do become financially rewarding, then the whole picture changes with at least a chance that the space program shall become self sustaining.
I am convinced that we are in a small window of time in which we will either see humankind become an interplanatary mutiworld species within the lifetime of many of those living today or we will forever turn our backs on such ventures, grinding on to our ultimate and inevitable extinction, a passing which will be little noted nor remembered by an unimpressed universe. In the old (1933) melodramatic scifi movie Things to Come (based on H.G. Wells “conversation “The Shape of Things to Come”) a noted scientist and political leader named Cabel (played by a famous actor of the period, Raymond Massey), after launching the first spacecraft to the Moon despite violent opposition to the venture and to all forms of human progress, addressed a skeptical public (using somewhat politically incorrect terms but with significant relevence to our current situation):
“For Man, no rest and no ending. He must go on. Conquest beyond conquest. This little planet and all the laws of mind and matter that restrain him.Then the planets about him and then across the immensity of the stars. And when he has conquered all the depths of space and all the mysteries of time still he will be beginning. If we are (no) more than animals (who) only snatch at our little scraps of happiness, we live and suffer and (die) mattering no more than all other animals do or have done.” (He points at the stars) “Is it that…or this? The whole universe…or nothingness?… Which will it be?”
A bit corny? Perhaps, but if you have a greater vision of the destiny of mankind, I would be interested to hear it. (Please no religion. I have neither the interest nor the patience for such impossible to resolve debates).
* Silent Running is a very unusual movie, a unique blend of SciFi, space opera, cute robots, allegory, tragedy, environmental warning, murder and suicide with a botonist as its primary protagonist. It contains one of the most moving single lines in any movie not called To Kill A Mocking Bird. To the best of my memory it went something like this: “When I was a boy I put a message in a bottle and threw it into the ocean. I never learned if anyone found it.” To learn why this is so great a line, watch the movie. You won’t regret it.
**Finding decent science fiction today is difficult. One of my pet peeves is that fantasy, magic, sword and soccery, wizards, horror, dragons, vampire series etc. are all placed within the genre of “SciFi.” at most book stores and libraries They are actually as far from traditional SciFi as any literature could be. Although speculative in nature, true SciFi is in large measure based on scienctific knowlege or reasonable extrapulations from such knowledge.
*** what we didn’t suspect then was that these early failures would prompt an unprecedented interest in science in general and space in particular and eventually led to Kennedy’s announcement of the goal of placing a man on the Moon. It was for the wrong reasons, a overwhelming concern that we were “behind” the Russians, but it did wake the nation at least for awhile from the smug certainty that America would surely prevail in all fields over all other countries without effort or commitment.
****The extremely ill advised abandonment of the goal of returning to the Moon has led to the following quip: “Question: What are the most important items Americans will need when we return to the Moon? Answer: A passport and a Chinese visa.” Yes, I support both a Moon Colony and a Mars mission. Although essentially unrelated (no, the Moon is not a stepping stone to Mars except perhaps metaphorically) both ventures are critical if humans are to become a spacefaring species.
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