The March 2021 Edition
of the ISEC Newsletter
is Dedicated to the Memory of Jerome Pearson
In this Issue:
Tribute to Jerome Pearson
Editor’s Note
President’s Corner
Blue Marble Week
Architecture Note #36
Upcoming Events
Contact Us/Support Us
Jerome Pearson
(1938-2021)
by David Raitt, Ph.D. --ISEC Chief Historian
It is ironic that the February 2019 issue of the ISEC Newsletter was devoted to the memory of Yuri Artsutanov, co-inventor of the space elevator, while the February 2021 issue is devoted to the memory of the other co-inventor, Jerome Pearson. Jerome, born in 1938, passed away on 27 January in Mount Pleasant, South Carolina, and, while an aerospace engineer, a space scientist and an astronomer, he was probably best known as for his work on space elevators. He conceived the idea of the space elevator in 1969 while working at the NASA Ames Research Center, and perfected the concept in the early 1970s, when he was at the Air Force Research Laboratory in Ohio.
Jerome was involved in other projects through his company Star Technology and Research, based in Mount Pleasant, South Carolina., and conceived many original ideas for space technology, including a propellantless maneuvering space vehicle, a Moon and Mars gravity simulator for LEO, a zero-g massmeter, space debris removal, and a rocket or gun plus a rotating space tether for Earth-to-space launches. However, one of his main interests, for which he received study grants from NASA, was a lunar space elevator - a complete cis-lunar transportation system from LEO to the lunar poles and able to transport Earth supplies and structures to lunar bases, mines, and habitats, as well as transporting lunar regolith and other materials to LEO.
It was not until 1975 he finally managed to have his ideas on the space elevator published in an article “The Orbital Tower: A Spacecraft Launcher Using the Earth’s Rotational Energy” in Acta Astronautica. It was a definitive paper that announced the entry of the space elevator to the scientific community at large and was a major step forward to bringing the concept to reality. As the abstract stated, the theoretical possibility of constructing a tower to connect a geostationary satellite to the ground was examined. This ”orbital tower” could be built only by overcoming the three problems of buckling, strength, and dynamic stability. He surmized that the buckling problem could be solved by building the tower outward from the geostationary point so that it remained balanced in tension and stabilized by the gravity gradient until the lower end touched the Earth and the upper end reached 144,000 km altitude. The strength problem could be solved by tapering the cross- sectional area of the tower as an exponential function of the gravitational and inertial forces, from a maximum at the geostationary point to a minimum at the ends. The strength requirements were extremely demanding, but the required strength-to-weight ratio was theoretically available in perfect-crystal whiskers of graphite. Investigating the dynamic stability, it was found that the tower was stable under the vertical forces of lunar tidal excitations and under the lateral forces due to payloads moving along the tower. By recovering the excess energy of returning spacecraft, the tower would be able to launch other spacecraft into geostationary orbit with no power required other than frictional and conversion losses. By extracting energy from the Earth’s rotation, the orbital tower would be able to launch spacecraft without rockets from the geostationary orbit to reach all the planets or to escape the solar system.
Pearson and Artsutanov - co-inventors of the space elevator.
Although the Russian Yuri Artsutanov had published his ideas on a type of space elevator some fifteen years earlier in 1960, both men were unaware of each other’s work. Pearson’s work, in fact, made a leap beyond Artsutanov’s and set the stage for the modern design for space elevators. He asked his readers to imagine a physical connection being made between a satellite at geostationary orbit and the Earth’s surface below. He suggested that through the use of this connection, the deployment and return of satellites and spacecraft to and from the planet would be much safer, and require far less energy, which as a consequence, would also make them cheaper.
Like Artsutanov before him, Pearson recognized many of the finer mechanical details pertinent to the elevator’s construction and operation - such as the need for assembly to begin at the geostationary point so that the increasing weight of the cable reaching toward the planet could be counteracted by a separate cable extending into space. But, whereas Artsutanov imagined his counterweight attached at a distance of 60,000km, where it would double as a spaceport, Pearson fastened his at the much further distance of 144,000km. Pearson’s design did not call for a true counterweight per se as he believed the sheer distance and mass of the line, and the outward force placed upon it by the spinning planet, would be sufficient to keep the structure standing.
Instead of interplanetary vessels departing from the station like ships from a harbour as proposed by his Russian counterpart, Pearson saw the elevator directly employing the inertia generated by the centrifugal movement of the rotating system to slingshot craft away from the planet. He estimated that anything launched in this manner from appropriate distances above the geostationary point would be able to reach as far out as Saturn without using any form of rocketry. This meant that travelling to Mars, for instance, would require no more energy than what was needed to reach geostationary orbit. If spacecraft were launched from even further up the tower or extremely lengthy tether, Pearson theorized that the spacecraft would not require any self-propulsion at all to escape the solar system entirely.
Regarding the power that would be needed to reach geostationary orbit from the surface, Pearson, echoing Artsutanov, suggested that perhaps this energy could be supplied by a solar power station attached to the elevator system. Either that, or through the capturing of energy from returning climbers as they descended the line back to Earth, generated via friction from braking that could be reabsorbed into the line. His system would harness the rotation of the Earth to launch craft into space, thereby eliminating the need for rocket propulsion, while also generating its own power.
Pearson backed up his explanations of a space elevator with countless numerical calculations by which he thoroughly accounted for every technical aspect of his elevator’s design and operation, including the material of the line or tether, and its minimum strength-to-weight ratio. And, like Artsutanov, Pearson identified the need for the elevator’s cable to be tapered in order to prevent the line from breaking under the enormous tension that would be placed upon the system from both the downward pull of the planet and the counterweight being spun around it. Pearson also theorized that a suitable candidate might be found for the tether in perfect-crystal whiskers of graphite, a material whose tapering ratio would require that the cable be only ten times larger in diameter at geostationary altitude than on the surface.
In an historic meeting in St. Petersburg, Russia in August of 2006, the two inventors of the space elevator met for the first time, when Jerome Pearson visited Yuri Artsutanov and they talked, through an interpreter, outside the Hermitage Museum. Artsutanov related how he was given a sample of a high strength material and imagined a hanging cable that could be tapered to reach synchronous orbit. Pearson related how he was inspired by a description by Arthur Clarke of synchronous satellites “perched atop imaginary towers,” and figured out how to make the towers real. Yuri Artsutanov died on 1 January 2019. Please visit this link for that issue which includes four pictures of Jerome Pearson with Yuri.
Jerome Pearson and Arthur C. Clarke
Though it is Pearson to whom credit is given for bringing the space elevator first onto the world stage, his work published in 1975 soon found its way into numerous science fiction novels such as Arthur C. Clarke’s “The Fountains of Paradise”. Published in 1979, this seminal novel is often regarded to be the vanguard in bringing the space elevator to the attention of the wider public readership. Pearson actually provided technical expertise for Clarke when he was writing his science fiction classic, as he noted in his keynote presentation at the 2013 annual Space Elevator Conference in Seattle, where he talked at length about his long relationship with Clarke and showed many hitherto unseen images of Clarke and his work (http://spaceref.com/space-elevator/rare-jerome-pearson-video-speaking-on-the-space-elevator-concept.html).
It is noteworthy that Jerome Pearson was a participant at what is generally considered to be the first conference on the space elevator - the Advanced Space Infrastructure Workshop on Geostationary Orbiting Tether “Space Elevator” Concepts, organized by David Smitherman and held at NASA Marshall Space Flight Center, 8-10 June 1999. The references and bibliography in the proceedings of the workshop refer to several of Pearson’s works. They also refer to a couple of works by Arthur C. Clarke - his novel “The Fountains of Paradise” and his article “The Space Elevator: ‘Thought Experiment’ or Key to the Universe?” published in 1981.
Lunar Space Elevator
Pearson later extended the idea of a space elevator to the Moon, using the Lagrangian points as balance points in lieu of the geostationary orbit, and discovered that such a "lunar anchored satellite" could be used to bring lunar materials into high Earth orbit cheaply. Pearson presented the first paper on the lunar space elevator concept at the L5 Society European Conference on Space Settlements and Space Industries held in London in September 1977. He subsequently published his journal article on “Anchored Lunar Satellites for Cis-Lunar Transportation and Communication” in the Journal of Astronautical Sciences in March 1979. Interestingly, Artsutanov published a paper on a lunar space elevator just one month later, without either author being aware of the other.
From 2004-2005. Jerome was the Principal Investigator for a project supported by a NASA grant - Lunar Space Elevators for Cislunar Space Development. The final technical report for Phase 1 was published in May 2005 and proposed the lunar space elevator as a revolutionary method for facilitating development of cis-lunar space. The concept combined lunar space elevators with solar-powered robotic climbing vehicles, a system for lunar resource recovery, and orbit transfer space vehicles to carry the lunar material into high Earth orbit. The lunar space elevator as envisaged would provide a highway between Earth orbit and the Moon, to bring lunar products into Earth orbit, and to carry supplies from Earth orbit to lunar bases.
The system consisted of a lunar space elevator balanced about the L1 Lagrangian point on the near side of the moon, connected with surface tramways connecting the elevator ribbon with lunar mineral deposits and with ice deposits in craters near the pole. Robotic vehicles using solar power would carry minerals and propellants along the tramway and up the ribbon to beyond the L1 balance point. At the top of the elevator, the payloads were to be released into Earth orbit for construction of space complexes and for propellant depots for spacecraft leaving Earth orbit. In addition, payloads from Earth orbit could be propelled by ion rockets to the reverse elliptical orbits, and then rendezvous with the lunar space elevator to be carried down to the lunar surface.
Regarding performance and cost, the report concluded that such a lunar space elevator using existing high-strength composites with a lifting capacity of 2000 N at the base equipped with solar-powered capsules moving at 100 km/hour could lift 584,000 kg/yr of lunar material into high Earth orbit. Since launch costs may be about $1,000/kg then, this material would be worth more than half a billion dollars per year, resulting in greatly reduced costs and creating a new paradigm for space development.
To build the lunar space elevator and to operate it successfully would require that some key enabling technologies would need to be identified and addressed. One key technology was the application of advanced composites with better strength/density values, and the potential use of lunar materials. A second technology was the use of robotic construction on the lunar surface, preferably using indigenous materials, to reduce the cost of construction. A third was mastering the dynamics and control of the lunar space elevator structure itself. Finally, to make the system cost effective, the operation of the lunar space elevator and its components would have to be autonomous, to minimize the requirements for human operation or intervention.
It is worth mentioning that the Smitherman workshop in 1999 produced a summary of the current state of the space elevator and concluded that its construction was a long way off. Using the ideas and suggested materials, Bradley Edwards proposed a practical scheme for constructing a space elevator about the Earth in a more realistic timeframe and received NASA funding for a study. Such a happening is still some ways away. On the other hand, it is possible to build Pearson’s lunar space elevator now and use it to develop lunar resources and for lunar far side communication. It could also be constructed of existing composite materials and would not necessarily require the super-strength of carbon nanotubes.
Pearson’s papers at the IAC
Jerome Pearson gave many papers at conferences during his career and one of his earliest ones was based on his 1975 article in Acta Astronautica and presented at the 27th International Astronautical Congress in Anaheim, California, held 10-16 October 1976. His presentation was entitled “Using the Orbital Tower to Launch Earth-Escape Spacecraft Daily.”
Although Jerome was credited with being the co-inventor of the space elevator, along with Yuri Artsutanov, he was always mindful that other scientists and engineers had had similar ideas and he was at pains to document their research. Much of this is documented on his company’s website (http://www.star-tech-inc.com) under the heading Space Elevator History. But he also discussed it in several conference papers.
His paper entitled “Konstantin Tsiolkovski and the Origin of the Space Elevator” was presented at the 48th International Astronautical Congress held in Turin, Italy, from 6-10 October 1997. In this paper Pearson mentioned first Yuri Artsutanov’s invention and then his own, which he notes brought the concept of the space elevator to the world-wide astronautics community. But then the work of Konstantin Tsiolkovski came to light. In his presentation, Pearson reviews the relevant writings of Tsiolkovski and discusses his ideas and thought experiments. He then compares Tsiolkovski’s writings with the Artsutanov and Pearson space elevators as well as with other concepts for space tethers.
Jerome was also a keen and regular contributor to the sessions on the Space Elevator, organized by Dr. Peter Swan and Dr. David Raitt, under the auspices of the International Academy of Astronautics, at the annual International Astronautical Congresses.
The very first Space Elevator session, was held at the 55th International Astronautical Congress in Vancouver, Canada, from 4-8 October 2004. Jerome presented a paper entitled “The Lunar Space Elevator” based on his ongoing study for NASA. The paper examined his concept of lunar space elevators for development of the Moon. He described lunar space elevators as being flexible structures connecting the lunar surface with counterweights located beyond the L1 or L2 Lagrangian points in the Earth-Moon system. He believed a lunar space elevator on the Moon’s near side, balanced about the L1 Lagrangian point, could support robotic climbing vehicles to release lunar material into high Earth orbit. A lunar space elevator on the Moon’s far side, balanced about L2, could provide nearly continuous communication with an astronomical observatory on the Moon’s far side, away from the optical and radio interference from the Earth. Because of the lower mass of the Moon, such lunar space elevators could be constructed of existing materials instead of carbon nanotubes and would be much less massive than the Earth space elevator. The paper went on to review likely spots for development of lunar surface operations (south pole locations for water and continuous sunlight, and equatorial locations for lower delta-V), and examined the likely payload requirements for Earth-to-Moon and Moon-to-Earth transportation. The presentation also examined the system’s capability to launch large amounts of lunar material into high Earth orbit, concluded with a top-level system analysis to evaluate the potential payoffs of lunar space elevators.
In the Space Elevator session during the 57th IAC held in Valencia, Spain from 2-6 October 2006, Jerome returned to the subject of space elevator history with his presentation on “The Real History of the Space Elevator.” Here, he observes that the space elevator was invented twice, independently, and many ideas about space elevators were developed by multiple authors and inventors, some without knowledge of the others. The history of the field is somewhat muddled, so much so that some fairly recent papers have re-invented the concept. Some sources attribute the invention of the space elevator to Sir Arthur Clarke, in his novel from 1979. Others attribute it to Tsiolkovsky, writing in 1895. Part of the problem is that the original inventor of the space elevator, Yuri Artsutanov, published only in the youth-oriented Komsomolskaya Pravda. Even after John Isaacs and his colleagues came close to the concept of the space elevator in an article published in Science in 1966, there was no notice in the spaceflight engineering community. British authors Collar and Flower almost re-invented the concept in the Journal of the British Interplanetary Society in 1969, but again, the spaceflight engineering community did not pick up the idea. The independent invention by Jerome Pearson, published in Acta Astronautica in 1975, finally made the concept widely known. Now that there are significant efforts underway to develop the materials required to actually build a real space elevator, he thought it worthwhile to review the convoluted and somewhat mysterious history of the space elevator concept.
An active contributor to the International Space Elevator Consortium's monthly Skype History Committee meetings, Jerome's input and knowledge will be sorely missed. His obituary is found here.
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Editor’s Note
Dear Fellow Space Elevator Enthusiast,
I hope you liked reading about Jerome Pearson and his many contributions to the Space Elevator effort.
The above Memorial was written by David Raitt who has recently been given the title of Chief Historian for ISEC. Congratulations to David Raitt! If you are a subscriber to Quest, The History of Spaceflight Quarterly, he has contributed an article entitled: "Space Elevator Architectures." Congratulations, again!
David Raitt's name has been added to the "Who We Are" section of our website, along with some other notable names: Larry Bartoszek, David Dotson, and Paul Phister. Welcome to all!
Before I go, I'd like to point you to a podcast by one of our research assistants, Joshua Bernard-Cooper. Episode One of Space Forward was recently completed called, "Seeking Beyond the Rocket Equation--the Prospect of Space Elevators." Enjoy!
Sandee Schaeffer
Newsletter Editor
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President's Corner
by Pete Swan
Are we Ready to Proceed? Yes!
Last month I talked about my View of the Space Elevator Adventure. This month I will start with four of those items:
- Leadership MUST have a viable vision that is “way out there” while also being mission enabling - usually doing something no one else CAN do
- Usually there is NO business plan that seems real - but the vision leads to great success and rewards significantly beyond anything a financial analyst would predict - especially when looking at the impact on humanity of new infrastructure
- An early engineering assessment that says it can be done, if several items fall into place
- A clear and ready vision
If one were to think of Space Elevators as evolutionary in humankind's departure from the Earth, then one starts to recognize - that as with all journeys - the classic FIRST STEP must be taken. WE ARE TAKING THAT FIRST STEP NOW. The Space Elevator is revolutionary in that it changes the equation of delivery. The dynamics of massive tonnage versus the "limiting" rocket equation becomes the liberating movement of logistical cargo by electricity, while fulfilling customers' needs. It has so many promises and is seen as an enabler for so many dreams, that it must be pursued. Now! These dreams are important as they lead to specific visions of what can be done and are then transformed into need statements for developmental projects. Dreamers make things happen as much by spreading their enthusiasm early in a program. What we need are dreamers who stimulate the rest of us to action. The vision that is driving the Space Elevator community is:
Space Elevators are the Green Road to Space while they enable humanity's most important missions by moving massive tonnage to GEO and beyond. This is accomplished safely, routinely, inexpensively, daily, and they are environmentally neutral.
The Space Elevator community has arrived at two current realities:
- There should be a Dual Space Access Strategy which is partnership between future rockets and space elevators. The strengths of rockets will open up the Moon and Mars, while continuing to satisfy orbital needs around the Earth. In the near future Space Elevators will become the second road to space by moving massive amounts of cargo to grow the environments at GEO, the Moon and Mars. This partnership will leverage both strengths and enable humanity's bright future.
- The Space Elevator is closer than you think and is entering the Engineering Development Phase after successfully completing multiple Preliminary Technological Readiness Assessments (pTRA). As such, the Space Elevator is entering Phase Two of Development, which is to Validate Engineering Approaches.
Keep Climbing--and Dreaming!
Pete
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Blue Marble Week in Washington DC--Virtual, of Course
Providing a Better Understanding of Space Elevators
The Space Elevator Community has an opportunity to expand the world's knowledge about our mega-project though an organization called the Foundation for the Future. They are having a "Blue Marble Week" (monthly on different space topics) discussing the future of American Space Infrastructure. We are co-sponsoring the event (one day focus on an Earth Space Elevator) with the following words:
This event is co-hosted by ISEC, the International Space Elevator Consortium. (see LinkedIn location: https://www.linkedin.com/events/6770880414614618112/ )
"If one were to think of Space Elevators as an evolutionary approach for humans to leave the surface of the Earth, then one starts to recognize the essential step that must be taken. It is revolutionary in that it changes the equation of delivery dynamics--rocket equation limiting vs. massive movement of logistical cargo--while it fulfills the customer's needs. It has so many promises, and is seen as an enabler for so many dreams, that it must be pursued now."
Peter A. Swan, Ph.D.
Executive Director, ISEC
International Space Elevator Consortium
Sign up at: https://www.eventbrite.com/e/blue-marble-week-elevators-space-edition-tickets-136364438707
Our agenda for the 9th of March is:
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Architecture Note #36
by Michael A. Fitzgerald
Senior Exec VP and Co-Founder
Galactic Harbour Associates, Inc
Space Elevator Transportation & Enterprise Systems
Enterprise Region considerations within the
Galactic Harbour Architecture
The GEO Enterprise Region
(Third of three)
Personal Prolog
This is an Architecture Note. It is the opinion of the Chief Architect. It represents an effort to document ongoing science and engineering discussions. It is one of many to be published over time. Most importantly, it is a sincere effort to be the diary, or the chronicle, of the multitude of our technical considerations as we progress; along the pathway developing the Space Elevator.
Michael A. Fitzgerald
Are the GEO Region and the Apex Region…Enterprise Regions? (YES!)
In Architecture Note #35, the Apex Enterprise Region was portrayed. It is seen as the Galactic Harbour location where the Space Elevator Transportation System supports various interplanetary transportation enterprises. The interplanetary transportation activity is envisioned to be very active; not surprising --- since the velocity imparted is free and sufficient to arrive most anywhere in the near solar system. In the prelude, all that interplanetary vigor is made possible by the GEO Enterprise Region.
Where did these Enterprises come from?
The GEO Regions above the various Galactic Harbours will be the home to a wide variety of enterprises. At first, the enterprises will be clients/customers of a set of utilities; power, processing, and local transportation companies (e. g. small space tugs). These companies operate in a rhythm established the schedule of Space Elevator Climbers arriving with supplies from Earth, leaving with cargo headed to the Apex, and transshipping products headed down to the Earth Port.
The utilities will be there from early on, like the basic utilities at your first apartment -- power, lights, heat and maybe furnishings. Basic utilities, thus, are the first enterprises in each GEO Enterprise Region. In a sense, they are part of the Space Elevator Transportation System. Availability of basic utilities are necessary to attract the enterprises to move into GEO Region and the Apex Region. Some enterprises will move to GEO Region from elsewhere around the GEO belt; attracted by the various utilities mentioned above and the close proximity of the supportive Space Elevator.
What does this Enterprise Zone look like?
As you might suspect, the dynamic topography of the GEO Region Enterprise Zone is like no other place in the solar system. The Elevator’s Climber station is the center of action for the entire region. Near this center point, several “figure 8” orbit tracks can be seen, each crossing through the geosynchronous belt - accessible to the Climber station.
One orbit track serves as a parking lot; its purpose as classic as you might suspect. Along the orbit track are storage clusters, including spare parts, fuel cells, tools, and unspecified surplus items. Each of the items in the orbit are held in place by a tiny, thrust only, utility satellite. Everything in this and other orbits will be “tagged for tracking”. Things in GEO Region orbits need to be found, if only to be disposed, but most often to be used by one of the many enterprises in the GEO Region Enterprise Zone.
Another orbit holds satellites being refueled and refurbished. Yet another orbit holds a variety of factory, assembly, or foundry locations. One of these orbits serves as base for a variety of sensors of all sorts, examining the entire region - unwanted visitors are to be snared and disposed.
After a time, the taxonomy of orbital businesses melds together, becoming integrated, stronger, and efficient. The on-orbit supply chain emerges. It is likely that service companies will rent orbital slots, and fill them with attentive robotic insurance or banking factotums! Who knows!?
There are certainly more GEO Enterprise Region orbits to be established, and moving from orbit to orbit is also the essence of the region. The entire region is serviced by any number of space tugs and space taxis. These service enhancement spacecraft, likely powered by the most modern non-chemical thrust, will move cargo and tools from orbit to orbit with the elan of physics yet discovered. These same vehicles service the movement of cargo & products from Harbour to Harbour. – (A story I will tell when next we gather)
The GEO Region Enterprise Zone is quite a place. It cannot be better than the previous one, because there was none before it. It will be better in its next version -- because humankind demands it.
In Closing
The Space Elevator Enterprise System will be birthed in the GEO Region Enterprise Zone. I have no idea what it might be like, any more than I knew what that ARPAnet would grow to become. We have often said that we don’t know all the answers, but we do know that the path we are on will get us to the answers, and to our vision.
Fitzer
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Upcoming Events
Multi-Stage Space Elevator: Research and Development
Webinar Hosted by the International Space Elevator Consortium
Register at: www.isec.org/events
Saturday, March 6th, 2021, 2:00 PM to 3:00 PM UTC
Presented by John Knapman, Ph.D. FBIS ISEC Director of Research
Blue Marble Week
Sponsored by Foundation for the Future
Co-sponsored by the International Space Elevator Consortium
https://www.linkedin.com/events/6770880414614618112/
Tuesday, March 9th through Thursday, March 11th, 2021
Washington, D.C. (Virtual Conference)
Space Elevator Conference
Dual Space Access Architecture
Sponsored by the International Space Elevator Consortium
https://www.isec.org/events
Tuesday, May 25th through Wednesday, May 26th (Immediately before the ISDC, below)
Sheraton Gateway Hotel
Los Angeles, CA, USA
International Space Development Conference (ISDC)
Sponsored by The National Space Society
https://isdc2021.nss.org/home/
Thursday, May 27th through Sunday, May 30th, 2021
Sheraton Gateway Hotel
Los Angeles, CA, USA
72nd International Astronautical Congress
Sponsored by the International Astronautical Federation (IAF)
http://www.iafastro.org/events/iac/iac-2021/
Monday, October 25th through Friday, October 29th, 2021
Dubai World Trade Center
Dubai, UAE
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