Everyone on board knows that their benefactor acts out of purely personal motivations… but the true interests of the tycoon and the dangers that he conjures up are beyond anyone’s imagination.
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Ice Moon – The Boxset
All four bestselling books of the Ice Moon series are now offered as a set, available only in e-book format.
The Enceladus Mission: Is there really life on Saturn's moon Enceladus? ILSE, the International Life Search Expedition, makes its way to the icy world where an underground ocean is suspected to be home to primitive life forms.
The Titan Probe: An old robotic NASA probe mysteriously awakens on the methane moon of Titan. The ILSE crew tries to solve the riddle—and discovers a dangerous secret.
The Io Encounter: Finally bound for Earth, ILSE makes it as far as Jupiter when the crew receives a startling message. The volcanic moon Io may harbor a looming threat that could wipe out Earth as we know it.
Return to Enceladus: The crew gets an offer to go back to Enceladus. Their mission—to recover the body of Dr. Marchenko, left for dead on the original expedition. Not everyone is working toward the same goal. Could it be their unwanted crew member?
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Proxima Rising
Late in the 21st century, Earth receives what looks like an urgent plea for help from planet Proxima Centauri b in the closest star system to the Sun. Astrophysicists suspect a massive solar flare is about to destroy this heretofore-unknown civilization. Earth’s space programs are unequipped to help, but an unscrupulous Russian billionaire launches a secret and highly-specialized spaceship to Proxima b, over four light-years away. The unusual crew faces a Herculean task—should they survive the journey. No one knows what to expect from this alien planet.
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Proxima Dying
An intelligent robot and two young people explore Proxima Centauri b, the planet orbiting our nearest star, Proxima Centauri. Their ideas about the mission quickly prove grossly naive as they venture about on this planet of extremes.
Where are the senders of the call for help that lured them here? They find no one and no traces on the daylight side, so they place their hopes upon an expedition into the eternal ice on Proxima b's dark side. They not only face everlasting night, the team encounters grave dangers. A fateful decision will change the planet forever.
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Proxima Dreaming
Alone and desperate, Eve sits in the control center of an alien structure. She has lost the other members of the team sent to explore exoplanet Proxima Centauri b. By mistake she has triggered a disastrous process that threatens to obliterate the planet. Just as Eve fears her best option may be a quick death, a nearby alien life form awakens from a very long sleep. It has only one task: to find and neutralize the destructive intruder from a faraway place.
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The Hole
A mysterious object threatens to destroy our solar system. The survival of humankind is at risk, but nobody takes the warning of young astrophysicist Maribel Pedreira seriously. At the same time, an exiled crew of outcasts mines for rare minerals on a lone asteroid.
When other scientists finally acknowledge Pedreira’s alarming discovery, it becomes clear that these outcasts are the only ones who may be able to save our world, knowing that The Hole hurtles inexorably toward the sun.
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Silent Sun
Is our sun behaving differently from other stars? When an amateur astronomer discovers something strange on telescopic solar pictures, an explanation must be found. Is it merely artefact? Or has he found something totally unexpected?
An expert international crew is hastily assembled, a spaceship is speedily repurposed, and the foursome is sent on the ride of their lives. What challenges will they face on this spur-of-the-moment mission to our central star?
What awaits all of them is critical, not only for understanding the past, but even more so for the future of life on Earth.
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The Rift
There is a huge, bold black streak in the sky. Branches appear out of nowhere over North America, Southern Europe, and Central Africa. People who live beneath The Rift can see it. But scientists worldwide are distressed—their equipment cannot pick up any type of signal from it.
The rift appears to consist of nothing. Literally. Nothing. Nada. Niente. Most people are curious but not overly concerned. The phenomenon seems to pose no danger. It is just there.
Then something jolts the most hardened naysayers, and surpasses the worst nightmares of the world’s greatest scientists—and rocks their understanding of the universe.
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Mars Nation 1
NASA finally made it. The very first human has just set foot on the surface of our neighbor planet. This is the start of a long research expedition that sent four scientists into space.
But the four astronauts of the NASA crew are not the only ones with this destination. The privately financed ‘Mars for Everyone’ initiative has also targeted the Red Planet. Twenty men and women have been selected to live there and establish the first extraterrestrial settlement.
Challenges arise even before they reach Mars orbit. The MfE spaceship Santa Maria is damaged along the way. Only the four NASA astronauts can intervene and try to save their lives.
No one anticipates the impending catastrophe that threatens their very existence—not to speak of the daily hurdles that an extended stay on an alien planet sets before them. On Mars, a struggle begins for limited resources, human cooperation, and just plain survival.
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Mars Nation 2
A woman presumed dead fights her way through the hostile deserts of Mars. With her help, the NASA astronauts orphaned on the Red Planet hope to be able to solve their very worst problem. But their hopes are shattered when an unexpected menace arises and threatens to destroy everything the remnant of humanity has built on the planet. They need a miracle—or a ghost from the past whose true intentions are unknown.
Mars Nation 2 continues the story of the last representatives of Earth, who have found asylum on our neighboring planet, hoping to build a future in this alien world.
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Mars Nation 3
Does the secret of Mars lurk beneath the surface of its south pole? A lone astronaut searches for clues about the earlier inhabitants of the Red Planet. Meanwhile, Rick Summers, having assumed the office of Mars City's Administrator by deceit and manipulation, tries to unify the people on Mars with the weapons under his control. Then Summers stumbles upon so powerful an evil that even he has no means to overcome it.
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A Guided Tour of Neptune
The solar system’s outermost planet is a hotspot, even though it revolves around the sun at such a distance. There are blustery high-speed storms in its atmosphere. In addition, large vortex systems like those on Jupiter are not uncommon. Neptune’s moon, Triton, which orbits the planet in the ‘wrong’ direction, is also a puzzle.
Those visiting the solar system for the first time could easily take its two outer planets for siblings. Uranus and Neptune are nearly the same size and glow blue in visible light. Neptune, however, seems to have gotten a little bit more of everything. It’s a little heavier and considerably denser than Uranus. The sphere looks much bluer and, most notably, is more temperamental.
Temperamental Planet
Primarily because of its temperament, Neptune has presented planetary scientists with several problems. This is because, as every Neptune tourist knows, the sun’s heat here is about one-thousandth of what it is on Earth, 33 times less than on Jupiter, and approximately half as strong as on Uranus. Nevertheless, the Neptune storms
that scientists have measured are probably the fastest in the solar system, reaching up to 2,100 kilometers per hour, or six times the speed of Earth’s strongest storms. And the cloud bands that usually wind around the planet like stripes move at 1,500 km/h at the equator and 600 km/h at the poles.
There’s a lot of energy that goes into this movement, and scientists are still puzzling over its origins. There is no observable planetary contraction, which is the primary source of Jupiter’s energy. One possible mechanism could be the waste heat from radioactive decay. Neptune is denser than Uranus, so comparable layers are exposed to higher pressures on Neptune. Under such conditions, methane may be converted into other materials such as diamond and long-chain hydrocarbons. Such heavier reaction products would then slowly sink toward the planet’s core, and energy would be released from the friction.
Finally, it is also conceivable that the violent movement in the lower atmosphere could cause disruptions in Neptune’s gravitational waves, releasing energy. The exact functioning of these processes is not known, but their results are clearly observable. Temperatures of up to 500 degrees have been observed in the upper atmosphere, for example. And then there are the big, long-lasting storms.
For instance, Voyager 2 discovered an anticyclone similar to Jupiter’s Great Red Spot, which is the size of the Eurasian continent. This storm did not appear in subsequent observations with the Hubble telescope, though there was a similar spot in the northern hemisphere. Then there was ‘scooter,’ a cyclone that raced around Neptune in 16 hours. Voyager 2 also photographed the ‘Little Dark Spot,’ likewise a cyclone. The assumption is that the individual dark areas permit a view of the underlying cloud layer, while bright spots are indicative of gas rising from the inside.
Beautiful, Blue Neptune
The atmosphere of Neptune is, as is the atmosphere of Uranus, very complex. Anyone attempting to reach the planet’s core would first encounter a layer of hydrogen and helium, the density of which is slowly increasing. The planet’s blue color is attributable to the traces of methane. Herein lies another mystery. While the two planets have similar levels of methane, Uranus is less of a sky blue and more of an ocean green. Does this mean that Neptune’s atmosphere contains additional substances that have not yet been discovered? Ultraviolet radiation partially decomposes methane into ethane and ethyne. In addition, traces of carbon monoxide and hydrogen cyanide have been detected.
As pressure increases with depth, the methane starts to condense, forming the clouds of the topmost layer. Beneath it, there are additional cloud layers of ammonia, ammonium sulfide, hydrogen sulfide, and ultimately, water. However, at the level of the water clouds, the conditions are already uncomfortable, with pressure here at 50 atmospheres and the temperature at around zero degrees. The farther down you go, the warmer it gets. As the pressure increases even more, the water and methane are soon frozen.
But don’t imagine that the ice is like the cubes in your Moscow mule. This ice is basically a hot, very dense, and viscous flowing liquid that is, in terms of texture, more comparable to lava. This area is known as the water ammonia ocean. Since the liquid can conduct electricity, it is also responsible for the formation of the magnetic field.
Superionic water
It is possible that at this depth, the pressure becomes so great that the bonds of water molecules break apart. The oxygen atoms then arrange themselves in the shape of a lattice, while the hydrogen ions—which are identical to protons—move freely through the lattice. This state of aggregation, which is only hypothetical, since it has only been produced in computer simulations, is called superionic. The material would be as hard as steel and shine bright yellow, though it would still have the characteristics of a liquid because of the free hydrogen ions.
Neptune’s Core
Inside Neptune, there seems to be a solid core that is similar to Earth’s. It is estimated that its temperatures reach 5,200 degrees, and that it consists of iron, nickel, and rock, with a mass about 1.2 times that of Earth’s.
Since Neptune’s axis is oblique to its orbital motion, its seasons are pronounced. While temperature differences of ten degrees between summer and winter seem minor to Earthlings, it’s important to bear in mind that the sun warms the planet far less. While one year on Neptune lasts about 165 Earth years, one day—a rotation around its own axis—is just 16 hours.
A Place in the Sun
If you ever end up on Neptune, it’s best to choose a dwelling right where the sun shines. If you stay close to the poles, you’ll likely have sunlight around the clock for the rest of your life. However, you’ll have far less of it than you would on Earth—something like the intensity of the light from a full moon, for example. It would be harder to decide at what elevation to park your flying home. Although the air pressure on the surface is as high as it is on Earth and the gravitational acceleration on the surface is only slightly higher than what you’re used to, it’s not exactly homey at minus 201 degrees.
The Exploration of Neptune
Neptune was the first planet to be discovered indirectly. In 1821, relatively early in terms of mapping the solar system, astronomers noticed something strange about the orbit of Uranus. The calculations eventually led to the discovery of Neptune in 1846 at almost the exact position that had been predicted. The discoverer was therefore not Johann Gottfried Galle, the German astronomer who first saw it in the telescope—even Galileo is sure to have noticed it, though not recognized it as a planet—but rather the Frenchman Urbain Le Verrier, who gave the accurate projections that made it possible to finally track down Neptune.
It was Le Verrier himself who had initially suggested the name Neptune, for the Roman god of the sea. However, he then attempted to give the new planet his own name, an idea that was not received enthusiastically outside of France. The English then advocated for the name Oceanus, while the Germans preferred Janus. Neptune prevailed, and this is what the planet is referred to in almost all of the world’s languages. Only the Greeks make an exception with Poseidon, after the Greek god of the sea.
The Ring System
Neptune also has a ring system. As with Jupiter and Uranus, it is not very bright, which means that it is more likely to consist of rock dust rather than ice. It is almost reddish in color, and it likely receives new materials from asteroids that crash into Neptune’s moons.
There are unusual clumps—accumulations of material within the rings—which led astronomers to initially suspect that the rings were not complete. Presumably they are attributable to the gravitational effects of the ring moons.
Particularly striking is the Adams ring, named after discoverer John Couch Adams, which is the outermost of the rings. It contains five clearly visible arcs bearing French names: Courage, Liberté, Egalité 1, Egalité 2, and Fraternité. The existence of these arcs contradicts the ring formation theory, according to which the material had to distribute uniformly in a relatively short period of time. According to one theory, it is the nearby moon Galatea that is responsible for these disturbances. In fact, some of the arcs seem to be short-lived. Liberté, for example, may already be gone in 100 years.
Neptune’s Companion
Thus far, astronomers have detected 13 moons around Neptune. The biggest is Triton, which, with its ice geysers, is unquestionably the most exciting. Generally, it is possible to distinguish the inner and the outer moons. The inner moons are closely connected to the ring system and move regularly, or in the direction of the planet’s rotation, around Neptune and consist mostly of ice. Nevertheless, they are quite dark because their surfaces are contaminated by dark materials that are theorized to be organic compounds.
Orbiting the planet further out are the irregular moons, including Triton. Scientists suspect that Triton migrated from somewhere outside, and that its arrival disrupted Neptune’s moon system. For example, it may have forced Nereid, the third-largest moon, into its now very eccentric orbit.
Triton is easily the leader in terms of mass. It accounts for m
ore than 99 percent of the total mass of the moons. Triton likely threw the original inner moons out of their orbits, and when they collided, the fragments formed the rings and today’s inner moons.
For Neptune, there is an advantage to being so far out in the solar system—the planet can keep its moons on a longer leash without needing to worry about them being stolen away by the competition. The distance between Neptune and its two moons Psamathe and Neso, probably created by the break-up of an earlier celestial body, is 125 times greater than the distance between the Earth and our moon.
Nereid—the Eccentric Moon
Before the Voyager 2 spacecraft made its trip, there was knowledge of only two Neptunian moons, Nereid, which was discovered in 1949, and the mighty Triton. Nereid owes its discovery to its very eccentric orbit, which brings it almost as close as a million kilometers from Neptune before it swings out to a distance of 10 million kilometers. The moon was either captured by Neptune from the Kuiper belt or thrown into this orbit by Triton.
The Triton Disaster: Hard Science Fiction Page 27
