What If We Do Find Aliens?


Time to talk about my favorite topic: aliens.

We’ve covered the Fermi Paradox many times over several articles on Universe Today. This is the idea that the Universe is huge, and old, and the ingredients of life are everywhere. Life could and should have have appeared many times across the galaxy, but it’s really strange that we haven’t found any evidence for them yet.

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What Is The Interplanetary Transport Network?

What is the Interplanetary Transport Network?

It was with great fanfare that Elon Musk announced SpaceX’s plans to colonize Mars with the Interplanetary Transport System.

I really wish they’d stuck to their original name, the BFR, the Big Fabulous Rocket, or something like that.

The problem is that Interplanetary Transport System is way too close a name to another really cool idea, the Interplanetary Transport Network, which gives you an almost energy free way to travel across the entire Solar System. Assuming you’re not in any kind of rush.

When you imagine rockets blasting off for distant destinations, you probably envision pointing your rocket at your destination, firing the thrusters until you get there. Maybe turning around and slowing down again to land on the alien world. It’s how you might drive your car, or fly a plane to get from here to there.

But if you’ve played any Kerbal Space Program, you know that’s not how it works in space. Instead, it’s all about orbits and velocity. In order to get off planet Earth, you have be travelling about 8 km/s or 28,000 km/h sideways.

Artist's concept of a Bimodal Nuclear Thermal Rocket in Low Earth Orbit. Credit: NASA
Artist’s concept of a Bimodal Nuclear Thermal Rocket in Low Earth Orbit. Credit: NASA

So now, you’re orbiting the Earth, which is orbiting the Sun. If you want to get to Mars, you have raise your orbit so that it matches Mars. The absolute minimum energy needed to make that transfer is known as the Hohmann transfer orbit. To get to Mars, you need to fire your thrusters until you’re going about 11.3 km/s.

Then you escape the pull of Earth, follow a nice curved trajectory, and intercept the trajectory of Mars. Assuming you timed everything right, that means you intercept Mars and go into orbit, or land on its surface, or discover a portal to hell dug into a research station on Phobos.

If you want to expend more energy, go ahead, you’ll get there faster.

But it turns out there’s another way you can travel from planet to planet in the Solar System, using a fraction of the energy you would use with the traditional Hohmann transfer, and that’s using Lagrange points.

We did a whole article on Lagrange points, but here’s a quick refresher. The Lagrange points are places in the Solar System where the gravity between two objects balances out in five places. There are five Lagrange points relating to the Earth and the Sun, and there are five Lagrange points relating to the Earth and the Moon. And there are points between the Sun and Jupiter, etc.

Illustration of the Sun-Earth Lagrange Points. Credit: NASA
Illustration of the Sun-Earth Lagrange Points. Credit: NASA

Three of these points are unstable. Imagine a boulder at the top of a mountain. It doesn’t take much energy to keep it in place, but it’s easy to knock it out of balance so it comes rolling down.

Now, imagine the whole Solar System with all these Lagrange points for all the objects gravitationally interacting with each other. As planets go around the Sun, these Lagrange points get close to each other and even overlap.

And if you time things right, you can ride along in one gravitationally balanced point, and the roll down the gravity hill into the grasp of a different planet. Hang out there for a little bit and then jump orbits to another planet.

In fact, you can use this technique to traverse the entire Solar System, from Mercury to Pluto and beyond, relying only on the interacting gravity of all these worlds to provide you with the velocity you need to make the journey.

Welcome to the Interplanetary Transport Network, or Interplanetary Superhighway.

Unlike a normal highway, though, the actual shape and direction these pathways take changes all the time, depending on the current configuration of the Solar System.

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A stylized example of one of the many, ever-changing routes along the ITN. Credit: NASA

If you think this sounds like science fiction, you’ll be glad to hear that space agencies have already used a version of this network to get some serious science done.

NASA greatly extended the mission of the International Sun/Earth Explorer 3, using these low energy transfers, it was able to perform its primary mission and then investigate a couple of comets.

The Japanese Hiten spacecraft was supposed to travel to the Moon, but its rocket failed to get enough velocity to put it into the right orbit. Researchers at NASA’s Jet Propulsion Laboratory calculated a trajectory that used the Lagrange points to help it move slowly and get to the Moon any way.

NASA’s Genesis Mission used the technique to capture particles from the solar wind and bring them back to the Earth.

There have been other missions to use the technique, and missions have been proposed that might exploit this technique to fully explore all the moons of Jupiter or Saturn, for example. Traveling from moon to moon when the gravity points line up.

It all sounds too good to be true, so here’s the downside. It’s slow. Really, painfully slow.

Like it can take years and even decades to move from world to world.

Imagine in the far future, there are space stations positioned at the major Lagrange points around the planets in the Solar System. Maybe they’re giant rotating space stations, like in 2001, or maybe they’re hollowed out asteroids or comets which have been maneuvered into place.

Exterior view of a Stanford torus. Bottom center is the non-rotating primary solar mirror, which reflects sunlight onto the angled ring of secondary mirrors around the hub. Painting by Donald E. Davis
Exterior view of a Stanford torus. Bottom center is the non-rotating primary solar mirror, which reflects sunlight onto the angled ring of secondary mirrors around the hub. Painting by Donald E. Davis

They hang out at the Lagrange points using minimal fuel for station keeping. If you want to travel from one planet to another, you dock your spacecraft at the space station, refuel, and then wait for one of these low-energy trajectories to open up.

Then you just kick away from the Lagrange point, fall into the gravity well of your destination, and you’re on your way.

In the far future, we could have space stations at all the Lagrange points, and slow ferries that move from world to world along low energy trajectories, bringing cargo from world to world. Or taking passengers who can’t afford the high velocity Hohmann transfer technique.

You could imagine the space stations equipped with powerful lasers that fill your ship’s solar sails with the photons it needs to take you to the next destination. But then, I’m a sailor, so maybe I’m overly romanticizing it.

Here’s another, even more mind-bending concept. Astronomers have observed these networks open up between interacting galaxies. Want to transfer from the Milky Way to Andromeda? Just get your spacecraft to the galactic Lagrange point in a few billion years as they pass through each other. With very little energy, you’ll be able to join the cool kids in Andromeda.

I love this idea that colonizing and traveling across the Solar System doesn’t actually need to take enormous amounts of energy. If you’re patient, you can just ride the gravitational currents from world to world. This might be one of the greatest gifts the Solar System has made available to us.

Finding “The Lost Science” of 2001: A Space Odyssey

The film 2001: A Space Odyssey brought space science to the general masses. Today we may consider it as common place, but in 1968 when the film was released, humankind had yet to walk on the Moon. We certainly didn’t have any experience with Jupiter. Yet somehow the producer, Stanley Kubrick, successfully peered into the future and created a believable story. One of his methods was to employ Frederick I. Ordway III as his science consultant. While Ordway has since passed, he left behind a veritable treasure trove of documents detailing his work for Kubrick. Science author and engineer Adam K. Johnson got access to this trove which resulted in the book “2001: The Lost Science – The Scientist, Influences & Designs from the Frederick I. Ordway III Estate Volume 2“. It’s a wonderful summary of Ordway’s contributions and the film’s successes.

What makes a movie? A plethora of ingredients must come together. But most of all, the audience must accept it for what it proclaims to be. For instance, a science fiction show must wander about in space and/or time. And the audience has to believe the wandering. In the 1960s, the general audience had little knowledge of space and could conceivably believe in anything.

Many films used expediency over truth, such as using a gun to shoot a capsule to the Moon. However, to validate his film, Kubrick enlisted Ordway from the Future Projects Office of the Marshall Space Flight Centre. Presumably this alone would have added large amounts of veracity, but Ordway took on the challenge as we see in Johnson’s book and pushed further.

9781926837352

Ordway interviewed many scientists and engineers. Many of these came to the set to provide advice. Ordway acquired drawings as well as made his own schematics. He went to industry, academia and governments. Johnson skillfully brings this all to light. How did the results mesh with this effort? That is the value of Johnson’s book. It gives credit to the breadth and depth of Ordway’s research.

The book’s first section identifies the knowledge sources; people like Willy Ley, books such as Beyond Tomorrow The Next 50 Years in Space, and organizations such as Boeing and its PARSEC project. It identifies the individuals who came to the filming sets to give advice and has many images of the sets as well.

The second section gives credit to preceding films, though it’s not certain from Johnson’s book as to how or if Ordway drew inspiration from them.

Its third and final section is probably the most fun as it provides many figures of the mock-ups, drawings and schematics. It includes a great full page image of Space Station V and a four page pullout section of Discovery X-Ray Delta One. There’s also an interesting note therein that indicates that the sets and props had to be thoroughly believable from every perspective, as they didn’t know where Kubrick may place the camera. Thus, the book gives the reader a taste of the fine detail for some graphics such as for the Moon Bus. With Johnson presenting all this from Ordway’s collection then it’s easy for the reader to understand why there’s a high sense of believability to the film.

Yes, Johnson’s book shows the amount of knowledge that was available in the early 1960s and that Ordway gained access to much of this information. The very large size of this book, about 11in by 14.5in helps show off many great images throughout. However, its size also suggests the style of the book; that is, it is a scrapbook. The book is a wonderful compendium of information relevant to the film 2001: A Space Odyssey. But it doesn’t add to the knowledge base. It’s an excellent repackaging of existing material with only a little suggestive comments on cinematic technique that might be original. And, as with most scrapbooks, the value of this book is the images. While the text is informative, it’s also somewhat dry, so the reader will probably feel much greater reward from feasting on the many print reproductions, drawings and photographs within Johnson’s book.

Perhaps the greatest value of this book is what goes unstated. That is, with enough effort and research people can construct a likely overview of humankind’s progress into the near future.  A future than can be thrilling. The book “2001: The Lost Science – The Scientists, Influences & Designs from the Frederick I. Ordway III Estate Volume 2” by Adam K. Johnson captures some of the excitement and thrill as humankind lay poised upon the edges of travelling into space. Reading it will give you pause at just how far we’ve progressed in the last 50 years. And perhaps get you thinking about what the films of today might be telling us about the next 50 years.

How Do We Terraform The Moon?

Welcome back to our ongoing series, “The Definitive Guide To Terraforming”! We continue with a look at the Moon, discussing how it could one day be made suitable for human habitation.

Ever since the beginning of the Space Age, scientists and futurists have explored the idea of transforming other worlds to meet human needs. Known as terraforming, this process calls for the use of environmental engineering techniques to alter a planet or moon’s temperature, atmosphere, topography or ecology (or all of the above) in order to make it more “Earth-like”. As Earth’s closest celestial body, the Moon has long been considered a potential site.

All told, colonizing and/or terraforming the Moon would be comparatively easy compared to other bodies. Due to its proximity, the time it would take to transport people and equipment to and from the surface would be significantly reduced, as would the costs of doing so. In addition, it’s proximity means that extracted resources and products manufactured on the Moon could be shuttled to Earth in much less time, and a tourist industry would also be feasible.

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