This morning’s post grows out of listening to John Coltrane’s album Sun Ship earlier in the week. If you’re new to jazz, Sun Ship is not where you want to begin, as Coltrane was already veering in a deeply avant garde direction when he recorded it in 1965. But over the years it has held a fascination for me. Critic Edward Mendelowitz called it “a riveting glimpse of a band traveling at warp speed, alternating shards of chaos and beauty, the white heat of virtuoso musicians in the final moments of an almost preternatural communion…” McCoy Tyner’s piano is reason enough to listen.
As music often does for me, Sun Ship inspired a dream that mixed the music of the Coltrane classic quartet (Tyner, Jimmy Garrison and Elvin Jones) with an ongoing story. The Parker Solar Probe is, after all, a real ‘sun ship,’ one that on December 24 of last year made its closest approach to the Sun. Moving inside our star’s corona is a first – the craft closed to within 6.1 million kilometers of the solar surface.
When we think of human technology in these hellish conditions, those of us with an interstellar bent naturally start musing about ‘sundiver’ trajectories, using a solar slingshot to accelerate an outbound spacecraft, perhaps with a propulsive burn at perihelion. The latter option makes this an ‘Oberth maneuver’ and gives you a maximum outbound kick. Coltrane might have found that intriguing – one of his later albums was, after all, titled Interstellar Space.
I find myself musing on speed. The fastest humans have ever moved is the 39,897 kilometers per hour that the trio of Apollo 10 astronauts – Tom Stafford, John Young and Eugene Cernan – experienced on their return to Earth in 1969. The figure translates into just over 11 kilometers per second, which isn’t half bad. Consider that Voyager 1 moves at 17.1 km/sec, and it’s the fastest object we’ve yet been able to send into deep space.
True, New Horizons has the honor of being the fastest craft immediately after launch, moving at over 16 km/sec and thus eclipsing Voyager 1’s speed before the latter’s gravity assists. But New Horizons has since slowed as it climbs out of the Sun’s gravitational well, now making on the order of 14.1 km/sec, with no gravity assists ahead. Wonderfully, operations continue deep in the Kuiper Belt.
It’s worth remembering that at the beginning of the 20th Century, a man named Fred Mariott became the fastest man alive when he managed 200 kilometers per hour in a steam-powered car (and somehow survived). Until we launched the Parker Solar Probe, the two Helios missions counted as the fastest man-made objects, moving in elliptical orbits around the Sun that reached 70 kilometers per second. Parker outdoes this: At perihelion in late 2024, it managed 191.2 km/sec, so it now holds velocity as well as proximity records.
191.2 kilometers per second gets you to Proxima Centauri in something like 6,600 years. A bit long even for the best equipped generation ship, I think you’ll agree. Surely Heinlein’s ‘Vanguard,’ the starship in Orphans of the Sky was moving at a much faster clip even if its journey took many centuries to reach the same star. I don’t think Heinlein ever let us know just how many. Of course, we can’t translate the Parker spacecraft’s infalling velocity into comparable numbers on an outbound journey, but it’s fun to speculate on what these numbers imply.
Image: The United Launch Alliance Delta IV Heavy rocket launches NASA’s Parker Solar Probe to touch the Sun, Sunday, Aug. 12, 2018, from Launch Complex 37 at Cape Canaveral Air Force Station, Florida. Parker Solar Probe is humanity’s first-ever mission into a part of the Sun’s atmosphere called the corona. The mission continues to explore solar processes that are key to understanding and forecasting space weather events that can impact life on Earth. It also gives a nudge to interstellar dreamers. Credit: NASA/Bill Ingalls.
Speaking of Voyager 1, another interesting tidbit relates to distance: In 2027, the perhaps still functioning spacecraft will become the first human object to reach one light-day from the Sun. That’s just a few steps in terms of an interstellar journey, but nonetheless meaningful. Currently radio signals take over 23 hours to reach the craft, with another 23 required for a response to be recorded on Earth. Notice that 2027 will also mark the 50th year since the two Voyagers were launched. January 28, 2027 is a day to mark in your calendar.
Since we’re still talking about speeds that result in interstellar journeys in the thousands of years, it’s also worth pointing out that 11,000 work-years were devoted to the Voyager project through the Neptune encounter in 1989, according to NASA. That is roughly the equivalent of a third of the effort estimated to complete the Great Pyramid at Giza during the reign of Khufu, (~2580–2560 BCE) in the fourth dynasty of the Old Kingdom. That’s also a tidbit from NASA, telling me that someone there is taking a long term perspective.
Coltrane’s Sun Ship has also led me to the ‘solar boat’ associated with Khufu. The vessel was found sealed in a space near the Great Pyramid and is the world’s oldest intact ship, buried around 2500 BCE. It’s a ritual vessel that, according to archaeologists, was intended to carry the resurrected Khufu across the sky to reach the Sun god the Egyptians called Ra.
Image: The ‘sun ship’ associated with the Egyptian king Khufu, in the pre-Pharaonic era of ancient Egypt. Credit: Olaf Tausch, CC BY 3.0. Wikimedia Commons.
My solar dream reminds me that interstellar travel demands reconfiguring our normal distance and time scales as we comprehend the magnitude of the problem. While Voyager 1 will soon reach a distance of 1 light day, it takes light 4.2 years to reach Proxima Centauri. To get around thousand-year generation ships, we are examining some beamed energy solutions that could drive a small sail to Proxima in 20 years. We’re a long way from making that happen, and certainly nowhere near human crew capabilities for interstellar journeys.
But breakthroughs have to be imagined before they can be designed. Our hopes for interstellar flight exercise the mind, forcing the long view forward and back. Out of such perspectives dreams come, and one day, perhaps, engineering.
Transit time of 6,600 years; that long ago, around 4,600 BCE, the state of human civilization was devoid of technology. Hard to imagine what would happen back home on Earth during a journey of that length.
Cut it in half? That long ago, around 1,300 BCE, we were in the Iron Age and saw the rise of empires. The Inited States has only existed 250 years and it’s future is uncertain.
I’m trying to raise a question about whether we have misconceived what should be the long term existential project of our civilization? For example, just in terms of Gene Roddenberry’s “Prime Directive”, Ethically, how could we launch an exploration mission when we can’t, and likely won’t, know what awaits at the other end?
I’m old. In 1956 I read all the science fiction books in the Phoenix public library. Later I read Doc E.E Smith, and titles such as “Starman Jones”, Childhood’s End, Ender’s Game, etc. Entertaining stuff! But as advertised, fiction.
I just wonder if humanity’s adventurous nature is leading us away from a proper focus on the sustainability of our civilization, our specie, and our fragile planetary environment?
Wouldn’t this apply even if we could travel FTL?
I don’t expect a generation ship to last millennia, so I would expect any passengers and crew to be in stasis for the trip. They won’t be coming back to Earth. Therefore, their technology and social system would be irrelevant when they reached their destination. The most likely meeting of the contemporary crew and a future crew would be if a slow ship is overtaken by a later, faster ship. Then you would have the possible clash of 2 very different cultures. Often overlooked is that the later ship might be slower, so that on a long flight, the cultural and technological difference could be millennia, even if the 2 ships set out only a few years apart.
It depends on your timeframe.If humanity finds a way to survive for a billion years, then survival requires going to other star systems as our planet becomes unlivable. (We could survive in a Dyson swarm within our system.) Natural evolution suggests that a species might last 1-10 million years. Artificial evolution is likely to compress that time drastically. We can already tinker with our genomes, so would we be likely to remain the same species even a millennium from now? If we want our biosphere to survive, it will have to be seeded/recreated on other worlds.
The solutions we take might depend on whether life is ubiquitous or not. If it is vanishingly rare, why shouldn’t humanity colonize the galaxy? But suppose life is ubiquitous. Would the “Prime Directive” be enforced throughout time, or would our species’ push to survive suggest that humanity would colonize the stars whether or not it was interacting with or displacing other life?
We have no idea where our technology will lead us, and with it, our options. They are probably unimaginable to us today. Those options may expand exponentially if we seed new civilizations on many stars in the galaxy.
This is a particularly beautiful entry. The picture shows that 4500 years ago some very clever humans had a useful understanding of fluid flow, shaped their boat hull in accordance, and added a prow that embodied practicality and beauty hoping to send the vessel on an eternal voyage, and launchedit to a destination they would not see. Hopefully, we can do at least as well…
Beautifully put, Bill. Thank you.
How about some more inspiration: https://www.aol.com/ufo-spotted-hovering-over-canada-104036068.html
What do you find inspirational in a military aircraft shooting down a high altitude balloon?
“we are examining some beamed energy solutions that could drive a small sail to Proxima in 20 years”
Good, but then how do you start slowing down at the halfway mark, assuming an equivalent rate of deceleration? No way to carry enough fuel for that, and there ain’t nobody at the other end with a laser to slow you down. You gonna just fly by at 1% lightspeed? For what purpose? You can’t even communicate with the probe, because it would take 8 years plus to get any response… (4.2 light years to send, 4.2 light years to receive)
The Breakthrough Starshot concept is indeed for a ‘swarm’ flyby, with data return spread out over quite a few years. The objective is simply to get a photograph of an exoplanet up close. With all its flaws, the idea is the first to offer an interstellar probe mission at such speeds, and one that could be within reach of our technologies within a few decades.
Like it or not space based beamed power is coming, and as far as I have been able to find after many years of investigation, it represents the ONLY realistic possibility for interstellar space travel.
As far as the considerations of the long term survival of our species on Earth M.A.D. Has helped enormously in maintaining a sort of almost peace in the world for several decades. This is just as Olberth envisioned when he laid much of the foundation for modern rocketry. However as time goes by the same old forces and tendencies of people and nations will inevitably lead to new technologies being developed that will make rocket delivered nuclear weapons obsolete. We’re almost there now actually. This is both concerning and exciting. Concerning because in a laser based defense environment M.A.D. may no longer apply. Asymmetry in control of large scale space lasers could lead to a single country or group of countries being able to control the whole world through military means. If the lasers are in place in GSO or GEO they could effectively cover the whole of the surface of Earth and be unreachable by any conventional weapons. Without the assurance of mutual destruction holding radical leaders in check the missiles just might fly after all. In the short or medium term this potential future could be extremely oppressive or nearly utopian in terms of a global Pax Lux (the peace of the laser). But how it turns out is more fine grained than I want to explore. A further application of space based lasers is of course energy production off planet and with no significant greenhouse gas emissions or pollution. Immediate crises such as global warming could be mitigated somewhat by moving power production off Earth.
The same technology that is currently being developed to put large scale laser weapons in orbit could also alleviate global warming and is also the most effective method for interstellar travel. In such a future as I have outlined in which a single group gains control of overwhelming power and enforces a global paradigm of peace I predict that the Earth would stagnate and fall backwards into ignorance. While the interstellar colonies would be able to continue to move forward and expand and adapt.
As with most disruptive technologies this one can and will be used for both harm and good. I hope that it could be built and maintained by a consortium of free democratic societies rather than one dictatorship.
Good discussion on the subject of warp drives, if you want to get someplace before you left.
“Post-Alcubierre Warp-Drives | Daniel Davis”
The Alcubierre Drive is brilliant physics, but it’s over 30 years old. Daniel Davis explores 13 modern warp drive concepts that overcome the limitations of Dr. Miguel Alcubierre’s original design. FULL INTERVIEW:
https://youtu.be/0tGU2pSLtwI
I just can’t see it taking thousands of years to get to another star system, technology improves and we can transmit the engine designs to the craft or even send matter and energy via beamed routes.
OT
Looks like an Oort cloud object has been found.
https://www.astronomy.com/science/astronomers-have-spotted-the-most-distant-comet-ever-discovered/
The Alcubierre Warp Drive will never become obsolete because it is the only model of the warp drive that used the gravitational field equations of general relativity. I don’t see anything new in this posted video Post-Alcubierre warp drive except for the idea. I think it is a mistake to assume some kind of geometry like a bubble to explain the space warp of a warp drive because it is only a crude analogy. First Alcubierre did not get his inspiration from the cosmology, but general relativity.
The idea of runaway motion by Bonner and Bondi 1957 and Forward 1964 does apply to the warp drive and of course the perpetual motion machine and diametric drive. As far as the energy conditions are concerned, the positive idea is correct since if we consider that gravity can both contract and expand space as in the crests and troughs of a gravity wave, then the energy conditions are in no way violated.
The idea of reversing the vectors to the space expands is where the problem of the misconception of the Alcubierre warp drive began. Negative energy was erroneously assumed to be some kind of deficit of energy or lower than zero which is not correct. I think we should be changed to positive energy, but with negative curvature and therefore no Casimir effect is needed, an idea which leads away from the possible production of any possible effect for a warp drive or anti gravity.
The expansion of space and the negative curvature cannot be removed from the back of the FTL warp drive, because the runnaway motion is lost and therefore the free fall geodesic and any hope for FTL. The space has to contract in front of the ship to pull it forwards and that can best be achieved with gravitational radiation concentrated on a central point in front of the ship which would create an artificial mass. Anti gravity waves make a negative mass or curvature behind the ship.. Therefore the non inertial frame is simply a pocket of local, non inertial space and not any kind of a solid bubble. The pocket can only exist at C and greater which takes one into hyperspace.
Alcubierre warp drive problems solved.using ordinary, first principles of physics.
A manned Interstellar journey by just one craft is close to impossible. Like a lone ant trying to cross a chasm. A team of ants can cooperate and link a chain that allows a good fraction of them to cross. So I think it is with a journey to the stars.
Lots of infrastructure would be required, made up of craft/stations/relays helping with the outbound and incoming journeys. We need to lay the tracks before the bullet train can run.
Is there any example of a study into the requirements of a mature manned Interstellar transportation system?
Good question, Roger, and I’d better throw that open to the readers. I think the only examples of mature manned interstellar transportation systems would be found in science fiction, but maybe there are some papers I don’t know about.
When it comes to science fiction Alastair Reynold in his well received “Chasm City” envisioned a small fleet of slower than light ships travelling to other system. The humans onboard where consisted of a small group of small crew and hibernating colonists kept safe. Perhaps also notable is the fact that Reynolds proposed a one generation flight. Some members of the first crew are still alive when the fleet arrives at it’s destination. This idea avoids many famous pitfalls of a generation ship design, although some conflict is inevitable between generations.
He later used a similar idea in “On the Steel Breeze”, where there is a massive interstellar fleet of slower than light ships travelling together carrying millions of humans, I think this is more close to the idea Roger presented.
I’ve read Chasm City but haven’t gotten around to On the Steel Breeze. Good pointers!
I suppose we could have cyclers, they go to the stars are slowed down as they go around the star and back out again. Once we are at a target star we could have runways with fuel to be picked up to slow the large ships to swoop around the star and then propelled back out again. There are plenty of docs out there about it, all look to require huge infrastructures or leaps in tech.
https://arxiv.org/pdf/2402.15536
This is a poorly posed question. First you need to fully define the objective and timeline and only then propose candidate feasible solutions. You’ve proposed a vague skeleton of a solution while skipping that first critical step.
This question assumes that the initial forays with a lone or small fleet of ships have found a destination that is worth traveling to back and forth. Unlike travel on Earth, or even the inner solar system, STL starflight takes a long time. Why would it need some mature system, the equivalent of taking a scheduled train or flight to a destination that takes less than a week of travel?
If the technology supports beaming the information of a person and reconstituting them at the destination, the problem is still similar to STL ships, just that the travel time is the same as the distance in light years.
For a scheduled system, with short travel times, the technology would need to be FTL. We do not know how that would be done, and even if it could, the time paradoxes seem problematic given the current physics we have. FTL travel could be as simple as getting into a car and arriving at the destination within a short time. Is that “mature”? The technology seems to dictate this. We take trains, ships, and aircraft because these systems are generally too expensive to be owned by each traveler. Yet the wealthy and corporations do just that, needing no schedules, just a vehicle, with start and destination infrastructure, such as runways, terminals, customs, ports, etc.
If there are no suitable destinations, or no reason to have them within an economic sphere, then there may never be anything but exploratory starflight, much like exploration of the Earth in the 16th,17th, 18th, and 19th centururies by sailing ship, and pioneering flight in the 20th.
Using our Earth travel as analogs, my guess is that there will be some strflight, possibly for trade, if the return trips can be kept to no more than a decade, 5 years in each direction. The stars that can encompass will depend on the technology. For STL travel, Alpha Centauri is the only destination. With FTL, all bets are off, although in all cases, the cost will determine whether travel is undertaken and how frequently, and for what purpose.