If you look at Galaxy’s December, 1962 issue, which I have in front of me from my collection of old SF magazines, you’ll find a name that appears only once in the annals of science fiction publishing: George Peterson Field. The article, “Pluto – Doorway to the Stars,” is actually by Robert Forward, who was at that time indulging in a time-honored practice, concealing an appearance in a science fiction venue so as not to raise any eyebrows with management at his day job at Hughes Aircraft Company.
Aeronautical engineer Carl Wiley had done the same thing with an article on solar sails in Astounding back in May of 1951, choosing the pseudonym Russell Saunders as cover for his work at Goodyear Aircraft Corporation (later Lockheed Martin). Both these articles were significant, as they introduced propulsion concepts for deep space to a popular audience outside the scientific journals. While solar sails had been discussed by the likes of J. D. Bernal and Konstantin Tsiolkovsky, the idea of sails in space now begins to filter into popular fiction available on any newsstand.
But despite being frequently referenced in the literature, Forward’s foray into Galaxy did not focus on sail technologies at all. Instead, it dwells on an entirely different concept, one that Forward called a ‘gravitational catapult.’ This is itself entertaining, so let’s talk about it for just a moment before pushing on to the actual first appearance of laser beaming to a sail, which Forward would produce in a different journal in the same year.
Forward is the master of gigantic engineering projects. Pluto had caught his attention because its eccentric orbit matched up with what Percival Lowell had predicted for a planet beyond Neptune, but its size was far too small to account for its supposed effects. Lowell had calculated that it would mass about six times Earth’s mass, a figure later corroborated by W. H. Pickering. But given Pluto’s actual size, Forward found that if it were the outer system perturber Lowell had predicted, it would have to have a density hundreds of times greater than water.
Remember, this was 1962, and in addition to being a physicist, Forward was a budding science fiction author playing with ideas in Galaxy, which had just passed from the editorship of H. L. Gold to that of Frederick Pohl, a man of lively imagination and serious SF chops himself. Why not play with the notion of Pluto as artifact? I think this was Forward’s first gigantic project. Thus:
…we can envision how such a gravitational catapult could be made. It would require a large, very dense body with a mass larger than the Earth, made of collapsed matter many times heavier than water. It would have to be whirling in space like a gigantic, fat smoke ring, constantly turning from inside out.
The forces it would exert on a nearby object, such as a spaceship, would tend to drag the ship around to one side, where it would be pulled right through the center of the ring under terrific acceleration and expelled from the other side. If the acceleration were of the order of 1000 g’s, then after a minute or so it would take to pass through, the velocity of the ship on the other side would be near that of light…
Forward imagined a network of such devices, each of them losing a bit of energy each time they accelerated a ship, but gaining it back when they decelerated an incoming ship. The Pluto reference is a playful speculation that what was then considered the ninth planet was actually one of these devices, which we would find waiting for us along with a note from the Galactic Federation welcoming us to use it. A sort of ‘coming out present’ to an emerging species. I can see the twinkle in his eye as he wrote this.
In any case, we have to change the history of beamed sails slightly to reflect the fact that the Galaxy appearance did not deal with sails, despite having a name similar to an article Forward published in the journal Missiles and Rockets in that same year. “Pluto – Gateway to the Stars” ran in the journal’s April, 1962 issue as part of a series by various authors on technologies for sending spacecraft to other planets. I had never seen the actual article until my friend Adam Crowl was kind enough to forward it the other day. Adam’s collection of interstellar memorabilia is formidable and has often fleshed out my set of early deep space papers.
Here what Forward latches onto is the most significant drawback to solar sailing, which relies on the momentum imparted by photons. This is the inverse square law, which tells us that the push we can get from solar photons decreases with the square of our distance from the Sun. Solar sails lose their punch somewhere around the orbit of Jupiter. What Carl Wiley first discussed in Astounding was the utility of sails for interplanetary exploration. Forward wanted to go a lot farther.
“Pluto – Gateway to the Stars” ran through the options for deep space available to the imagination in 1962, homing in on antimatter and concluding “it would be a solution if you were a science fiction writer,” which of course Forward would become. But he noted “there are a few engineering details.” The first of these would be the problem of antimatter production. The second is storage. With both of these remaining huge problems today, it’s intriguing that Forward actually spends more of this article on antimatter than on his innovative laser concept but runs aground on the problem of gamma radiation.
When the hydrogen-anti-hydrogen streams collide, the matter in the atoms will be transformed into pure energy, but the energy will be in the form of intense gamma radiation. We can stop the gamma rays in heavy lead shields and get our thrust this way, but the energy in the gamma rays will turn into heat energy in the shields and it will not be long before the whole rocket melts. What is needed is a gamma-ray reflector – and such a material does not exist. In fact, there are strong physical arguments against every finding any such material since the wavelengths of the gamma rays are smaller than the atomic structure of matter.
But sails beckon, and here the innovation is clear: Leave the propellant behind. Forward made the case that standard reaction methods could not obtain speeds anywhere near the speed of light because their mass ratios would be appallingly high, not to mention thermal problems with any design carrying its own propellant plant and energy sources. For interstellar purposes, he mused, the energy source and the reaction mass would have to be external to the vehicle, as indeed they are in a solar sail. But to go interstellar, we have to get around the inverse square law. Hence the laser:
There is a way to extend the idea of solar driven sails to the problem of interstellar travel at large distances from the sun. This is to use very large Lasers in orbits close to the sun. They would convert the random solar energy into intense, coherent, very narrow light beams that can apply radiation pressure at distances of light years.
However, since the Laser would have to be over 10 kilometers in diameter, this particular method does not look feasible for interstellar travel and other methods of supplying propulsive energy from fixed power plants must be found.
The editors of Missiles and Rockets seem to have raised their eyebrows at this early instance of Forward’s engineering, as witness the end of their caption to the image that accompanied the text.
Image: This is the original image from the Missiles and Rockets article. Caption: Theoretical method for providing power for interstellar travel is use of a very large Laser in orbit close to sun. Laser would convert random solar energy into intense, very narrow light beams that would apply radiation pressure to solar sail carrying space cabin at distances of light years. Rearward beam from Laser would equalize light pressure. Author Forward observes, however, that the Laser would have to be over 10 kilometers in diameter. Therefore other means must be developed.
At this point in his career, Forward’s thinking leaned toward fusion to solve the interstellar conundrum, but as events would prove, he would increasingly return to beamed sails of kilometer scale, and power station and lensing structures that are far beyond our capabilities today. But if we ever do create smart assemblers at the nanotech level, the idea of megastructures of our own devising may not seem quite so preposterous. And this 1962 introduction to beamed sails is to my knowledge their first appearance in the literature. Today the concept continues to inspire research on beaming technologies at various wavelengths and using cutting edge sail materials.
Read this issue and the article here:
https://drive.google.com/file/d/15zYiir4_RvSgDlYfA9cF2QFwDugLk-1g/view
I am always surprised by the creativity of the sixties, surely linked to an era of prosperity and cultural freedom.
Thank Paul
Maybe. It could also be that in the past when we understood less (theory and data) there were fewer constraints on what we could imagine to be possible. The gauntlet that ideas must now pass leaves fewer survivors. We need to be more clever with our inventions. Even fiction is touched by this; suspension of belief doesn’t take us as far as it once did.
Thanks to Fred posting the link to the issue, I found that I was more interested in Willy Ley’s support of the space station and providing some history. Possibly by coincidence, Wernher von Braun published his “Space Frontier” in 1963 and also explained why he was a supporter of building a space station. The reasons and uses have largely proven unneeded, with the exception of space medicine and human adaptation to space, and the staging post for crewed interplanetary travel. These last if replaced by uncrewed vehicles largely disappear. All the other reasons have been obsoleted by robotic and automated vehicles. Even the US military’s spaceplane is uncrewed. Human welfare in space has proven a lot harder than von Braun envisaged, especially with his suggestion that perhaps 5 minutes in a centrifuge might take care of the effects of zero-g so that space stations need not be rotating with artificial gravity.
Although several nations have flown a variety of space stations, it is still not clear what purpose they serve. It seems unlikely they could serve as emergency shelters like mountain cabins, and unless we expect to have deep space ships carrying crews and passengers that must be built in space yards with human construction teams on site, why would we need to build such structures?
But Alex, remember Neal Stephenson’s Seveneves, where it is only through the ISS that humanity survives the lunar catastrophe ;-)
@Paul
I haven’t read Stephenson’s Seveneves. However, it is only fiction. ;-)
If NASA builds the Lunar Gateway, that may be the nearest to a shelter or refuge that we will have. Whether it makes any sense, IDK.
Here is the Wikipedia synopsis
@Robin.
Thank you. Sounds interesting. The last Stephenson I read was Anathem. I have teed up the Seveneves audiobook to listen to next.
Paul,
Every number of “Galaxy” digitalized are here and many other things. Help yourself :)
https://www.luminist.org/archives/SF/GAL.htm
Fred
Thanks, Fred. I love to see these online. I’m also fortunate enough to have preserved a set of Galaxy in paper form, so I’ve got the actual issues on my shelves here.
@Alex
“why would we need to build such structures?”
I think we should consider them as a step between the space lift and the teleportation of Star Trek, which imposed us by the constraint and the cost of materials. We do not yet master other technologies that would allow to mount “bridges heads” faster and cheaper elsewhere (moon). However there is something that appears with the 3D printer…
Forward’s presumption that Pluto must be built of collapsed matter if it was indeed the planet needed to explain planetary orbit perturbations reminds me of the Russian astronomer, Shklovsky’s, suggestion that Mars’ moon Phobos must be hollow as calculations indicated it was in a faster-than-expected decaying orbit, and therefore artificial. More calculations that proved errant, and not one of his better ones.
As @Ron said:
‘What is needed is a gamma-ray reflector – and such a material does not exist. In fact, there are strong physical arguments against every finding any such material since the wavelengths of the gamma rays are smaller than the atomic structure of matter.’
I wrote down somewhere and I am not sure if it’s been thought about before but probably has though. If you send an antimatter packet out at a large fraction of c and then send the matter out at a slight higher velocity they can be made to collide at a large fraction of c. The net result is the craft would not see the gamma rays anymore but shifted wavelengths better suited to reflection or absorbtion.
I reread the article which is still very precise (read p82): wasn’t Forward suggesting us to use neutron stars as catapults? Did he have the idea of the Pulsars before J. Bell ? ;) Now let’s imagine that an ETI has understood this principle, it would have to be close enough to a neutron star or a pulsar for its first “shot”. With a few ballistics, could we then determine a radius around the collapsed star or would this ETI be located?
Ignoring for the moment the slight detail that first we would have to reach a pulsar or black hole for a slingshot effect, we would also have to deal with these objects’ immense and intense radiation and magnetic fields.
How close would we need to get to either celestial body to utilize this effect? If this involves going through those deadly and destructive fields, what would we need to counter those effects? What might we lose from the vessel in the process of deflecting them? In the end, is it worth it?
Please note that on page six of the featured issue of Galaxy magazine that Pope Pius XII approved of space travel in 1956.
@LJK
…probably to be closer to God :)
Joking aside, He did not quite approve of space travel; He would suggest that it should be done “consciously”. I invite you to read this astonishing speech that he gave in 1956 to the participants of the seventh congress of the international astronautical federation…we discover a Pope technician ! (page in French that the friend Google will translate you)
https://www.vatican.va/content/pius-xii/fr/speeches/1956/documents/hf_p-xii_spe_19560920_federazione-astronautica.html
Thank you so very much for this, Fred! It did indeed make for fascinating reading.
For the record, Pope Paul VI was a big fan and supporter of space exploration. Not sure about the others, except that Pope John Paul II forgave Galileo a few centuries late. :)
I cannot recommend this relevant essay enough…
https://tofspot.blogspot.com/2013/10/the-great-ptolemaic-smackdown-table-of.html
Don’t forget the Vatican SETI conference under Benedict XVI. Took place at the Pontifical Academy of Sciences on the Vatican grounds from November 6-11 in 2009. Numerous major figures were there, including keynote addresses by Paul Davies and Jill Tarter.
Here is a link to a news item on that Vatican SETI Conference from 2009:
https://www.universetoday.com/44713/vatican-holds-conference-on-extraterrestrial-life/
This quote:
“This follows the statement made last year by the Pope’s chief astronomer, Father Gabriel Funes, that the existence of extraterrestrials does not preclude a belief in God, and that it’s a question to be explored by the Catholic Church.”
Never quite got how even accepting the concept of extraterrestrial life would somehow automatically cancel out the concept of God. I certainly do understand, however, how this idea that more advanced beings exist in the Universe and that some of them might pay us a visit would disturb those humans in seats of authority and power.
A vast and ancient Cosmos that shows just how small we and Earth are – well that’s okay because it is too abstract for most humans to grasp anyway and doesn’t negate the authority of those in power. But intelligent alien beings who might come to our planet for who knows what purposes – now that’s scary and must be deflected if not outright suppressed.
Reality is not going to go away, no matter how much some may want it to.
@LKJ
‘Never quite got how even accepting the concept of extraterrestrial life would somehow automatically cancel out the concept of God.”
…not God but faith. for a Christian, God exists for sure, whether there is extraterrestrial life or not. The question does not arise, but those of His creations, yes. He may have tinkered some ETI in a corner of the galaxy but He made it clear to rest on Sunday without giving us the answer; He thought that it would occupy us to seek:D
So the question is not whether an extraterrestrial life would cancel out the concept of God – this is the kind of thinking that leads to the stake:) – but whether one has faith or not…to each his answer. On a purely human level, it is obvious that Religion is a power …
Since we are talking about this subject, I must ask a question that has haunted me for a long time: how is it that our life form appeared on earth, a planet that is from what I had read I do not know anymore or, just in the right place on the edge of the galaxy, not too close to the center or we would have experienced intense radiation given the density of the objects and not too close to the edge either, or the speed of rotation of the galaxy would perhaps never have allowed organic development or maybe we would have been ejected? I am European and Christian but I must admit that it is a very surprising agreement…otherwise we should find life forms globally in the same places on other spiral galaxies?
@Fred
We are somewhat trapped in thinking our world is perfect for life as we evolved here and know no others. Everything fits our needs perfectly. So naturally we want to find very similar worlds to look for life. Until we have a decent catalog of living worlds we won’t know which types of worlds and their location in the galaxy are best. Everything else is just speculation, mostly based on our requirements.
Fred said on July 9, 2024 at 15:46…
“Since we are talking about this subject, I must ask a question that has haunted me for a long time: how is it that our life form appeared on earth, a planet that is from what I had read I do not know anymore or, just in the right place on the edge of the galaxy, not too close to the center or we would have experienced intense radiation given the density of the objects and not too close to the edge either, or the speed of rotation of the galaxy would perhaps never have allowed organic development or maybe we would have been ejected? I am European and Christian but I must admit that it is a very surprising agreement…otherwise we should find life forms globally in the same places on other spiral galaxies?”
This may be the case of the tail wagging the dog. It is not so much that we just happened to appear in what seems to be the right spot in the galaxy, but rather that we evolved because we WERE in the right spot at the right time.
This reminds me of Earth’s solar eclipses: The Moon can fit over the Sun during a total solar eclipse ideally so that it blocks the photosphere and allows us to see the solar coronae and prominences.
The Moon is 400 times smaller than the Sun, but the Sun is also 400 times farther from Earth than the Moon, thus the ideal fit.
Is this due to divine machinations? Or is it more because we just happen to be alive and aware enough at a time when the Moon is in the right distance of its orbit about Earth to make total solar eclipses?
Note that our natural satellite has been moving further away from our planet at a rate of five feet per century. So many ages ago, the Moon’s disk blocked the Sun during an eclipse wider than the Sun’s disk. Conversely, in just over one billion years’ time, the Moon will be far enough from Earth that we will never again have anything more than an annular solar eclipse at most.
More details here:
https://www.scientificamerican.com/article/total-solar-eclipses-are-cosmic-coincidences-that-wont-last-forever/
One problem of aliens and God is that the ME religions have man (humans) created in God’s image, literally a physical form rather than abstract. hence the many depictions of God, e.g. in the Sistine Chapel, God looks like an old man. If there are aliens, then unless they are all humans created by God, then they will be different from humans, and therefore logically their God would look like them. So God would have to take many physical formats and that pretty much ends the reasoning of physical relatedness. Either he would have a single form and therefore all aliens would be human, or there would be multiple Gods (a no-no for ME religions), or God would take many forms. But if he is the creator, why would not all life on exoplanets look exactly like Earth?
Add to the issue of spawning a son, and this sets up more complications (as James Blish’s novel “A Case of Conscience” explores.
I think this would put nails into the coffin of the Bronze Age explanation of creation, undermining the book of Genesis on which the rest of the sandcastle is based. One can certainly find creative explanations, but they become convoluted like the evangelical explanations of the bible predicting scientific discoveries they like.
The Pontifical Texts of the Vatican are surprising and invite meditation especially in the field of science, where finally religion has always had its words to say, for better or for worse. I think it’s a good idea to keep this philosophical link and not just focus on technology, as we are doing a little too quickly today (?) But the reverse is also true, the dogma can be dangerous : read “The Handmaid’s Tale” and think of poor G Bruno.
To my knowledge, JPII was not particularly enthusiast of astronomy (he would prefer football :) but he surely wrote beautiful things.
Let’s not forget that Krakow was also one of the largest center of astronomy in Europe in the Middle Ages where Copernicus worked and that the Vatican at its astronomical observatory in Castel Gondolfo and even a second…in Arizona! Paul, I think this is what you’re talking about:
https://www.pas.va/en/events/2009/astrobiology/final_statement.html
Yes indeed, Fred. Thank you for providing that link.
Regarding Giordano Bruno, while it is popular to assume, as with Galileo, that their modern views on the structures of the Sol system and the stars, along with comments on any extraterrestrial life, are what got them into so much trouble with the Roman Catholic Church, the reality is, as usual, not so cut and dried.
Quote from here:
http://galileo.rice.edu/chr/bruno.html
“It is often maintained that Bruno was executed because of his Copernicanism and his belief in the infinity of inhabited worlds. In fact, we do not know the exact grounds on which he was declared a heretic because his file is missing from the records. Scientists such as Galileo and Johannes Kepler were not sympathetic to Bruno in their writings.”
Not only did Bruno have some very radical beliefs for his day, but that he happened to land on certain key modern views of the heavens is probably what kept later folks interested in him. The truth is, Bruno was no scientist, but he was certainly a free thinker, something dangerous then and well as now.
More details here:
https://mathshistory.st-andrews.ac.uk/Biographies/Bruno_Giordano/
Bruno and Galileo both had big egos and Bruno especially did not know when to quit when it came to dealing and arguing with others. Galileo ignored and mocked the reigning Pope at the time. While this was never a good idea, Galileo poked at a guy who had the birds in the Vatican courtyard put down because their signing annoyed him.
They also picked a rough time to attempt major change: The Protestant Revolution was underway and the RCC was not fan of any more revolutions.
For more details done in a fun and very educational manner, I again cannot recommend this relevant essay enough…
https://tofspot.blogspot.com/2013/10/the-great-ptolemaic-smackdown-table-of.html
Well done, Larry. It always bothers me when these Renaissance figures are simplified to fit into modern conceptions and political ideas. As you say, their actual stories are quite complex.
Thank you, Paul. I bet you did not envision an essay on light sails would turn into a historical religious discussion. :^)
It is always easier to condense a historical figure into a few words and sound bites for general consumption. Things also got the way they did regarding Galileo, Bruno, et al due to certain political and religious agendas by others later on.
Galileo never intended to go against the Church or otherwise upset the apple cart. He just happened to be playing in a mine field and was lucky not to have ended up like Bruno.
The pro and anti-science stance made so much of in later centuries, where the Church was branded with the latter, is also a major simplification. For a long time in European history after the decline of the Roman Empire, the Church was the major supporter of science, or natural philosophy, in the West, not to mention other forms of education and historical preservation of ancient knowledge.
See here for more:
https://en.wikipedia.org/wiki/Science_and_the_Catholic_Church
The break was made in the Renaissance with the endorsement of rationalist philosophy (R.Descarte) We began to examine the world by ourselfes in a purely material aspect and thus to detach ourselves from Religion. We must not forget that the Christian world of the time was composed very roughly of a few rich people who had the knowledge and therefore the power (religious, some scholars and patrons) but the majority of peoples lived in a world of beliefs, they had no other points of reference than what the Catholic Church said in other words the priest on Sunday and the stained glass windows of our cathedrals were their only textbooks…
Indeed, simplifying history is not good. We have to put ourselves in the context of the times, think like the people before us. Notice one funny thing:
We speak freely of solar veils and we end up with religion. Such a discussion would probably never have taken place in medieval times except in a small circle of friends restricted at night with a candle in a cellar…judge the evolution of Thought;)
I think you and others will find this book fascinating:
https://en.m.wikipedia.org/wiki/The_Cheese_and_the_Worms
Will we ever reach Alpha Centauri, our closest neighboring star system?
Story by Sarah Wells • 4d
Our space-exploration ambitions have boldly taken humans to the moon, rovers to Mars and spacecraft to the outer reaches of the solar system. But could humans or spacecraft ever reach Alpha Centauri, the closest star system to our planet?
Alpha Centauri is about 4.4 light-years (roughly 25 trillion miles, or 40 trillion kilometers) from Earth and is home to three separate stars. The closest star, Proxima Centauri, also hosts an exoplanet that scientists believe could have the conditions necessary for life.
Full article here:
https://www.msn.com/en-in/news/techandscience/will-we-ever-reach-alpha-centauri-our-closest-neighboring-star-system/ar-BB1qJ8ya?ocid=BingNewsVerp
To quote:
But reaching this star system would be no small feat. NASA estimates that, using a space shuttle like NASA’s now-retired 122-foot-long (38 meters) Discovery, it would take close to 150,000 years to reach Alpha Centauri.
If humans could travel at the speed of light, we could reach Alpha Centauri in four years flat. However, the laws of physics dictate that only massless light particles called photons can reach this cosmic speed limit. So, while humans will probably never reach Alpha Centauri, it’s possible that spacecraft designed to go a much smaller fraction of the speed of light could reach these stars in a human lifetime. To even hope of getting a spacecraft up to top speed, scientists will need something much smaller than Discovery.
Marshall Eubanks, CEO of the startup Space Initiatives Inc and a fellow at NASA Innovative Advanced Concepts, is researching remote methods for visiting Proxima Centauri using swarms of picometer-sized spacecraft. (A picometer is one-trillionth of a meter.)
…
While Lubin stressed that a journey to Alpha Centauri would be a long-term endeavor, Eubanks said he’s confident that big advances could come this century.
“I think that we will reach the Alpha Centauri system, with small probes launching in the decade of the 2040s, and thus arriving in the 2060s,” Eubanks said. “Significantly larger probes should be possible by the end of the century, but without unexpected breakthroughs in propulsion physics, I think that crewed missions will be a task for the next century.”
NASA spacecraft captures 1st photo of its giant solar sail while tumbling in space
By Monisha Ravisetti
published yesterday
Don’t worry, it’s doing fine.
https://www.space.com/nasa-solar-sail-space-photo