The Icy Realm

Non-Fiction - by Peter Jekel

Ice is time solidified. —Gretel Ehrlich

When one reads the science fiction of Jules Verne, one cannot help but wonder if the man had some sort of supernatural powers. He is one of only a few science fiction writers who can truly be said to have predicted the future. Solar sails, lunar modules, splashdown landings after a space voyage and even a launch from southern Florida in his 1865 From the Earth to the Moon, electric submarines and Tasers are found in his 1868 20,000 Leagues Under the Sea at a time when the power of electricity was only in its infancy and newscasts, skywriting, videoconferencing are found in his 1889 short story, In the Year 2889.

Inventions were only one of his visions of the future. Also found in his In the Year 2889, he describes a planet, Olympus, found beyond the orbit of Neptune, with an orbital cycle of over 1300 years, five times greater than the orbit of Neptune, which at the time was thought to be the furthest region of our Solar System (Pluto was not discovered until 1930).

Verne was proved uncannily correct again. Out beyond the planet Neptune, there are objects known as trans-Neptunian objects, made up of bodies known collectively as the Kuiper belt, the closest of the trans-Neptunian objects, and then there is the Oort Cloud not to mention a possible Planet X or even a possible binary star partner of the Sun, called ominously, Nemesis. Not Olympus, perhaps, but evidence of a lot more beyond what was thought to be the edge of the Solar System.

The Kuiper Belt, also known as the Edgeworth-Kuiper Belt is found from the orbit of Neptune out to around fifty-five Astronomical Units (AU) from the Sun. It forms a ring around the Solar System made up of thousands and possibly even millions of smaller bodies made up of ices of water, ammonia and even methane and ethane. Though the objects are generally small in size, there are some objects that are officially large enough to be classed as dwarf planets; more and more are being discovered as telescope and space travel technologies improve. One object is very familiar to us, Pluto. When it was demoted from planet to dwarf planet, it shifted from being the furthest body from the Sun to now being the closest body of the Kuiper Belt to the Sun. It is also possible that Triton, a moon of Neptune, Chiron, a Trojan asteroid between Saturn and Uranus with comet-like behavior—one researcher even suggests that it is a dwarf planet—(NASA is also planning an expedition to this world), and even Phoebe, a moon of Saturn, actually were gravitationally attracted to their current parent planets early on in the Solar System’s history from the Kuiper Belt.

Ironically, though the belt of objects is named after Dutch-American astronomer, Gerard Kuiper, he did not actually discover it. He did however, earn his namesake in history for having predicted its existence way back in 1951. In fact, it was only in 1992 that his prediction proved to be correct, that the first object other than Pluto and its moon, Charon, were discovered, minor planet (15760) Albion. Since that time, there have been many more discoveries. It has been predicted that there are likely over one hundred thousand Kuiper Belt objects that are over one hundred kilometers in diameter. Interestingly enough, though Kuiper predicted its existence, he also felt that the system had long since “eroded” away and that we would never find it. One science fiction writer wrote of this possibility but from an alien’s perspective. In Robert Sawyer’s Illegal Alien, an alien race is unaware of the Kuiper belt since theirs had already cleaned out.

Though Kuiper predicted the existence of the belt (though his version indicated that it was long gone from the Solar System’s landscape), he certainly was not alone. Since the discovery by Clyde Tombaugh of Pluto in 1930, astronomers across the globe had speculated that there had to be something more out there mainly to explain anomalies in the two ice giants of the outer Solar System, Uranus and Neptune. Very soon after Tombaugh’s discovery, American astronomers Frederick Leonard and Armin Leuschner speculated that there had to be something further out and that Pluto was only the first trans-Neptunian body to be discovered.

In 1943, British astronomer (as well as engineer, Army officer and economist) Kenneth Edgeworth, also a namesake for the alternative name of the Belt, came up with the idea of the Belt and published it in the Journal of the British Astronomical Association, that went a step further by providing a possible explanation for the Belt’s formation. He theorized that the primordial solar nebula that would eventually form the objects of the Kuiper Belt was not dense enough to collapse into planets but could support a number of smaller objects. He felt that based on this hypothesis that beyond the planets that there were a number of smaller objects that only occasionally made their appearance in the inner Solar System by becoming a highly eccentrically orbiting comet.

Though large in its extent, the Kuiper Belt likely occupies less than ten percent of the mass of the Earth. It is by no means a uniform body of objects either. The largest fraction of objects are known as the classical objects. They are called classical as the objects are what astronomers had expected to find prior to their actual discovery. In other words what was expected is that the Belt would be comprised of smaller objects that orbited the Sun much like the planets in almost circular orbits. That is exactly what most of the classical objects do. However, that is only a part of the entire story.

Within the classical belt, there is a further division known as hot and cold objects. Despite the nomenclature it has nothing to do with the temperature of the objects at all, but instead it describes the influence of Neptune on their orbits. The cold objects experience little influence from the planet Neptune and have maintained their stable orbits for billions of years and as a result have orbits very much like that of the planets in their almost circular orbits. They also appear redder in colour than the “hot”objects suggesting a methane/ethane ice surface and there are far more binary objects such as dwarf planets with almost an equally sized moon. On the other hand, there are hot objects exhibit more eccentric orbits because they are highly influenced by Neptune and during these interactions with the planet’s gravity well, the orbits have changed over the years, becoming more elliptical as well as slowly moving out of the orbital plane of the planets.

Why the names? Cold objects have uniform orbits out in the outskirts of the Solar System well away from the warming rays of the Sun. Hot objects, on the other hand, have a tendency, due to their more eccentric orbits, to come in closer to the Sun at some points in their orbits, hence they are “hotter.”

The Kuiper Belt also has a section called the scattered disc which stretches far beyond the Kuiper Belt proper. Objects of the scattered disc have been moved to these nether reaches of the Solar System after being flung out by the slingshot effects of Neptunian gravity. The orbits of scattered disc objects are highly elliptical, more so than the hot classical objects, and inclined tens of degrees to the plane of the planetary orbits. So one could say that the Kuiper Belt has been misnamed. Due to the bulge caused by the orbits of the scattered disc objects, the Kuiper Belt is less a belt shape than a torus (a three-dimensional version of a circle).

Pluto is known as the “King of the Kuiper Belt” since it is the largest object in the region. There are other objects of comparable size though. The dwarf planet, Eris is one; in fact, there was a time when it was thought that Eris was a larger Solar System body than Pluto. Pluto was on the verge of getting demoted in its status again but it was spared. Since its original discovery though, Eris has been found to be similar in size to Pluto, not larger, but it does have a larger mass. Discovered on October 21, 2003 by a group of astronomers at the Palomar Observatory in California, it is three times further out from the Sun than Pluto. It orbits the Sun every 557 years and has a day a little longer than that of the Earth at 25.9 hours. Like Pluto, it has a rock/ice surface and ranging in temperature from -217 C to -243 C. It does have an atmosphere that like Pluto’s, freezes and thaws out as it journeys around the Sun. Eris has a very small moon called Dysnomia which orbits the main body every sixteen days.

Though relatively newly discovered, Eris has still made it into several tales of science fictions. Charles Stross’ Saturn’s Children, is about an intelligent robot and its travels through the Solar System; the climax of the story takes place on Eris. Dani and Etyan Kollin used, in their The Unincorporated Man, Eris as a settlement site for a puritanical group.

Another dwarf planet of the Kuiper Belt is Haumea. It takes around 305 years to complete an orbit of the Sun. It was discovered on March 31, 2005 by a group of astronomers (the same group that discovered Eris) at the Palomar Observatory. It rotates on its axis every 22 and a half hours. Like Pluto and Eris, it too has a thin atmosphere that freezes and thaws in its orbit about the Sun. It also has a moon that unlike the other Kuiper Belt dwarf planets has a relatively boring name. It is called S/2015 (136472) and nicknamed an equally boring MK 2.

The dwarf planet, Quaoar, was the first such object discovered in the Kuiper Belt outside of Pluto and Charon, being first discovered on June 4, 2002. It is around 1200 kilometers in diameter based on measurements taken from the Hubble Space Telescope. Very close to the orbital period of Pluto it circles the Sun every 284.5 years. Its day is shorter than the other Kuiper Belt Objects at around 17.68 hours. The surface is moderately red suggesting methane and ethane ices. More interesting though is that there are signs that some of the ices are crystalline in nature, suggesting that there is freezing and thawing on the surface.

Why this freeze-thaw cycle happened is a matter of speculation. A couple of theories include a barrage of meteors that heated the surface or more likely cryovolcanism caused by some internal heating of the world. Cryovolcanism would be evidence of a possible subsurface ocean much like is suspected with Pluto. A subsurface ocean suggests the possibility of life. Imagine what life might be like in a seemingly inhospitable place.

Some authors have done exactly just that. Stephen Baxter envisioned an ice lifeform in the Kuiper Belt with liquid helium for circulation in his Sunpeople. Gregory Benford, in his Backscatter, a stranded prospector discovers a flower that exists on what he describes as an iceteroid in the Kuiper Belt.

On February 17, 2004, another dwarf planet Orcus, was discovered officially, though later analysis found that this object was seen on photographs that dated back to November 8, 1951. With the Spitzer Space Telescope its diameter is estimated to be around 958.4 kilometers in diameter; with such great distances, precise measurements are not possible. The dwarf planet orbits the Sun every 245.18 years at a distance of 4.53 billion kilometers from the Sun. Infrared observations by the European Southern Observatory and the Gemini Observatory in 2004, showed the likelihood of water ice. Another interesting finding, like Quaoar and Pluto, some of the ices on the surface are crystalline which could be an indication of cryovolcanism, also evidence of a subsurface ocean. The dwarf planet, like many others of the Kuiper Belt, does have a moon, Vanth around 260 kilometers in diameter.

A small world in the Kuiper Belt, Arrokoth, has actually been visited by NASA’s New Horizons spacecraft, which did a flyby on January 1, 2019, the first such mission to the Kuiper Belt beyond the Plutonian system. It is the furthest world to be explored by human craft. It was actually first detected in 2014 by the Hubble Space Telescope and was a designated target of the intrepid spacecraft. It is very red in colour but even stranger is its shape seen for the first time during the flyby. Instead of a standard and expected spherical shape, it is double-lobed, like a dumbbell, with two connected rounded pieces. It is extremely small around 35 kilometers long and around 20 kilometers wide. It orbits around 6.5 billion kilometers from the Sun taking 293 years. Unlike its lengthy orbit, it has a relatively quick day of around 15.92 hours. The lobes likely gently merged together early in the history of our Solar System as evidenced by the fact that they are so similar in colour.

Visionary writer Arthur C. Clarke’s 3001: A Space Odyssey, features a mission to the Kuiper Belt not for exploration, like New Horizons is doing, but for exploitation. In the case of the story, the mission was in order to mine ice for the eventual terraforming of Venus.

There are likely still a number of other large dwarf planets out in the Kuiper Belt waiting to be discovered. One thing is certain is that many of the ones that we have discovered so far have moons which are often as large as the main body, so that they are better described as binary dwarf planets. Since the Kuiper Belt Objects have altered little since their formation it is likely that the binary systems came about as a result of low velocity impacts that allowed both bodies to survive the impact and remain together by mutual gravity.

The Kuiper Belt is unlikely the major source of comets as was once thought. Some of the pieces of the Belt though do end up becoming short-period comets being pushed sunward by Neptune’s gravity and further harnessed by Jupiter’s enormous gravitational maw; these become known as the Jupiter-family comets with orbits of around twenty years. The trajectory of the comets from this region of space, would appear to be coming not from the classical regions but from the more eccentric objects of the scattered disc. Seems that Kuiper’s thought that the Belt that bears his name was correct but just a bit premature in his prediction of its demise. The Belt is slowly disintegrating from collisions producing smaller and smaller objects, some of which disappear into the void as dust which is then blown out of the Solar System by the strength of the solar wind, even at this far distance

Though the Kuiper Belt is far away, in terms of distance it is only a fraction as far as the Oort Cloud. The inner extreme of the Cloud is thought to be between two and five thousand AU from the Sun. The outer edge likely stretches to 100,000 AU from the Sun, the equivalent distance of almost halfway to our nearest stellar neighbour (outside of the Sun), Alpha Centauri. To envision this enormous distance of the Oort Cloud, just think that our Sun’s light reaches the Earth in eight minutes, whereas the outer edge of the Oort Cloud is seeing the Sun as it was a year and half ago, that is how long light takes to reach the icy realm.

The Oort Cloud envelopes the Solar System in a spherical bubble, very unlike the torus-shaped ring of the Kuiper Belt, and is made up of icy space debris. Though no objects have been observed directly, there is estimated to be upwards of trillions of objects, some the size of mountains out there in the Cloud. This is the region of space that is also likely the source of the long-period comets. One, called Siding Spring, made a very close approach to the planet Mars in 2014. No one will be around to see its return as it is not due for a showing in the inner Solar System for another 740, 000 years.

Where did this group of objects arise? The leading theory is that they were not always so far from the Sun. After planetary formation around 4.6 billion years ago, the “leftovers” were flung outwards by the gravity of the formed planets, mainly by the King of Planets, Jupiter, to the outer reaches of the Solar System.

Though some of these icy objects were flung clear of the Solar System altogether, others were held fast by the Sun’s powerful gravity. Though powerful in its gravitational tug, the Sun was competing with the gravitational field of the Galaxy as a whole and as a result the objects were pulled even further out before they settled in their present orbits.

The name of the Oort Cloud came from the Dutch astronomer who theorized the cloud’s existence to explain the source of long-period comets and the trajectories of their movements. Long-period comets come from all directions and not just the orbital plane of the planets that would be the case if the source were the Kuiper belt.

Other writers have envisioned life on the lonely worlds of the Oort Cloud. Peter Watts’ Blindsight, is about a mission to explore an object in the Oort Cloud that had been transmitting a radio signal. Frederick Pohl and Jack Williamson took it a step further and developed an entire ecology out in the Oort Cloud in their The Reefs of Space. Williamson also revisited the idea in his story, Lifeburst. Gregory Benford and fellow author, Paul Carter, envision Oort Cloud life in Iceborn. The novel describes a life form that can not only survive on Pluto but also out in the Oort Cloud.

In Robert Forward’s Camelot 30K an expedition is sent out to the Oort Cloud because of a radio signal received from there. The story describes the first contact with an alien civilization in a region of the Solar System that really is inhospitable to life as we know it due to the frigid temperatures. The world that is being explored has a temperature of thirty degrees Kelvin or -240 degrees Celsius. The title holds a clue to the temperature with the 30K.

The outer reaches of the Solar System may hold another surprise for us. Caltech researchers have come up with the mathematics that appears to indicate that there is likely an elusive Planet X beyond Neptune. One of the observations that suggest the existence of a larger Planet X is that the objects of the Kuiper Belt appear to orbit in clusters; the presence of the mysterious planet would explain this group movement. The movement of a particular dwarf planet in the Kuiper Belt, Sedna, also can be explained mathematically by the presence of another massive planet. The End of all Things, by John Scalzi is a complicated political thriller with two major human governments who don’t get along. Complicating things further is that the human governments have to contend with alien governments that both human governments do not get along with either. In the story, there is an abandoned station on the world of Sedna.

Planet X has been hypothesized in several science fiction stories for many years; some very early science fiction saw the planet’s potential for a story. John Jacob Astor IV wrote in 1894, A Journey to Other Worlds, about a mission to an icy trans-Neptunian world that he calls Cassandra. The planet holds one more surprise for the visitors; the planet is a haven for the souls of unworthy humans, not a lot different than the Christian Hell, only colder. The Destiny by Douglas Horner, written in 1912 describes a mission to Alpha Centauri. On the way out of the Solar System, the astronauts pass by a tenth planet. Horror writer, H. P. Lovecraft wrote of a world beyond Neptune called Yuggoth in The Whisper in Darkness.

Edmund Cooper’s The Tenth Planet, describes an advanced civilization on the distant world (“Tenth Planet” as at the time of the writing, Pluto was classed as a planet). Conversely, Larry Niven did not class Pluto as a planet (at the time of the writing in 1975 it was still classed as a planet) in his The Borderland of Sol, part of his Known Space series.

Philip K. Dick’s Solar Lottery involves a cult seeking to find a world beyond Pluto. Robert Heinlein in his juvenile novel, The Puppet Masters, writes of a planet beyond Pluto called Kalki. James Blish does the same in his Cities in Flight, which, too, describes a world beyond Pluto that he called Prosperina. In Joe Haldeman in his great, The Forever War, the beginning of the story takes place on a planet beyond Pluto which he calls, ironically Charon. The novel was written in 1974 before the discovery of Pluto’s first moon in 1978 which was subsequently called Charon. Robert Anton Wilson, in his trilogy, Schrodinger’s Cat, about a planet beyond Pluto which is called Mickey. An eleventh is discovered and it is called Goofy. Kim Stanley Robinson’s Galileo’s Dream, describes several outer gas giants beyond the orbit of Neptune, several of which had already been converted into energy required for time travel. Dean Smith and Kristine Rusch, wrote The Tenth Planet trilogy about a tenth planet twice as large as our moon. It is inhabited by aliens that occasionally during its millennial long-orbit around the Sun raid the Earth for resources. Greg Bear’s War Dogs trilogy also contains numerous planets beyond Neptune including the homeworld of the Antags with whom humans are at war. Interestingly the world is not natural, but artificial. It is maintained by the aliens as a sort of Dyson Sphere but instead of the shell surrounding a star, it surrounds a gaseous interior. The world is made inhabitable by a process of artificial fusion at its core.

In Larry Niven and Jerry Pournelle’s Lucifer’s Hammer, though it is about the effect of a cometary impact on the Earth, the comet’s origin is the result of a remote large world that disturbs the orbit of a comet and hurdles it towards Earth.

Is the Sun a part of a possible binary star system? It was originally theorized that there is a red dwarf or brown dwarf hovering at a distance of 95,000 AU from the Sun outside the Oort Cloud. The theory was not introduced to explain any movement of the Sun or any other astronomical phenomenon, but to explain mass extinctions in Earth’s history which appeared to occur every twenty-six million years. It was theorized that the other star perturbed the orbits of objects at the outer edge of the Solar System hurdling them towards the inner Solar System resulting in a multitude of impacts with the inner planets including Earth. In Poul Anderson’s Nemesis, a star interacts with the Oort Cloud hurdling objects inwards in a cometary shower of the inner Solar System.

In 2017, there was a paper published that the Sun did form as a part of other stars, but that they would have separated over four billion years ago. We also have the telescope technology today that would be able to detect something as dull as a brown dwarf at a distance of up to ten light years; nothing has been found. Our Sun is doomed to remain single the rest of its existence.

Instead more likely explanations for the periodicity of mass extinctions on Earth that it is possible that the close passage of other stars in the Galaxy or the angular effect of the galactic gravity plane working against the outer Solar System’s orbital plane causes the barrage of outer Solar System bodies to the inner Solar System, hence the mass extinctions. This is also known as the Shiva Hypothesis.

There is a whole new system of worlds out beyond the core of the Solar System. It is waiting to be explored by human craft-there are plans for new missions to the outer Solar System, after the enormous success of New Horizons. Until that time comes (it took New Horizons 26 years to accomplish its goal of reaching Pluto and unfortunately there was no backup so if it failed….) we can only wonder at what we may find. With current technologies as well as the data from New Horizons, the feedback is a source of wonder that goes well beyond a junkyard of icebergs.

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