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 Venus
Because it is the brightest object in Earth’s night sky after the moon, humans have known Venus since antiquity. It has one unusual feature—it appears only as a morning or evening star. Astronomers only figured out relatively recently why that is.
Venus’s Place in Space
Just like the Roman Goddess of Love, after whom the planet was named, it likes to hide its secrets behind a veil. You will learn what astronomers and space researchers have uncovered, despite the planet’s secrecy, as you read the following pages.
Venus orbits our central star with a near-perfect circular orbit, maintaining an average distance of 108 million kilometers from the sun. (The average distance from Earth to the sun is just under 150 million kilometers.) The deviation of Venus’s orbit from a perfect circle is less than that of any other planet in the solar system. Only a few asteroids have orbits that show smaller deviations. However, Venus does not move in the same plane as Earth around the sun—its orbit is inclined to the Earth’s orbit by about 3.4 degrees.
Venus’s orbit directly affects how it appears in Earth’s sky. Because Venus always has to be between us and the sun as we gaze outward from Earth, it appears as either a morning or evening star, but never at midnight. Did you know that Venus is the only planet that can cast a shadow on Earth? However, this only works in areas without light pollution, and only on nights when the moon does not outshine Venus. The planet can even be seen in the daytime sky, when it is right above the horizon.
Venus is also the planet whose orbit brings it closest to Earth. This occurs when Venus is furthest from the sun and Earth is closest to the sun—that’s the point when the two planets are in closest proximity. However, this happens quite rarely. We had the last Venus proximity in 1850, at 39,514,827 kilometers. In 2101 the distance will be 39,541,578 kilometers. But that’s still more than a hundred times the distance between Earth and our moon. By comparison, the shortest distance to Mars is about 54,000,000 kilometers.
The degree of Venus’s brightness in Earth’s sky has relatively little to do with its absolute distance from Earth, for, like the moon, it shows phases. However, they are only clearly visible with a telescope. Its greatest apparent brightness is minus 4.3. At that point, 30 percent of the sunlit surface can be seen. Its apparent size varies between 10 and 60 arc seconds.
Interestingly, over time, the orbits of Earth and Venus have adapted to each other. Their orbit durations have a ratio of 13:8—after 13 Venus orbits and 8 Earth orbits, they are in the same starting locations again.
Venus’s rotation about its axis is especially remarkable and unique. As you know, the Earth revolves once a day, rolling along its orbit—as if you were rolling a ball around the sun. Venus, however, rotates backward! It’s is like pushing a ball around the sun and revolving it once backward per complete orbit. However, there is no bound rotation. While an orbit around the sun takes 224 Earth days, Venus needs 243 days to complete one rotation around its axis. Since it moves around the sun while rotating, this results in a day length of nearly 117 Earth days—that is, every 117 days, the sun appears in the same spot in Venus’s sky. And due to the reverse rotation, it rises in the west and sets in the east. The only other planet that rotates in the ‘wrong’ (opposite) direction is Uranus.
Why the planet doesn’t rotate faster is not yet known. Astronomers suspect Venus was ‘grazed’ by an asteroid, which could have been the cause. It is also conceivable—and there is scientific evidence for this—that its dense atmosphere, which is heated up by the sun, plays a role.
Planet without a Moon
Like Mercury, the planet closest to the sun, Venus has no moon. We are not sure why that is the case. Some researchers argue that Mercury could even be a former moon of Venus. Others hypothesize that Venus’s moon—or moons—crashed into the planet a long time ago, perhaps as a result of an asteroid impact.
However, from Venus’s vantage point, the planet certainly has a companion. Asteroid 2002 VE68—the name tells you it was discovered in 2002—apparently ‘orbits’ Venus. That is, it is sometimes in front of it, sometimes behind it, and sometimes beside it. In fact, the approximately 400-meter wide asteroid orbits the sun. The asteroid’s orbit has a 1:1 resonance with Venus’s orbit. Viewed from Venus, this results in a kidney-shaped path, during which 2002 VE68 achieves a distance of about 30,000,000 kilometers from the planet on either side. This appears to have been true for the past 7,000 years, and will probably continue to be the case for another 500 years. Perhaps it was Earth’s gravitation that gave it its present orbit. In such a case, researchers speak of a quasi-satellite. It will also be the Earth that will push the quasi-satellite onto a different orbit one day when it flies past Earth.
The Atmosphere: Venus’s cloak
Like a modest goddess, Venus is always cloaked in a dense cloud cover. However, some of the planet’s properties can be determined from its trajectory. For instance, scientists have been able to calculate that the planet has about 81 percent of the Earth’s mass and 95 percent of the Earth’s radius.
Since Venus is a rocky planet like Earth, one can say it is Earth’s little sister. However, the resemblance is limited to size and weight. While the Earth likes to show every viewer its continents and oceans, Venus is covered by a dense, opaque atmosphere, indeed an exceptional atmosphere. It consists mainly of carbon dioxide (96.5 percent) and nitrogen (3.5 percent). There also are minute traces of sulfur dioxide. The atmosphere’s mass is 93 times that of Earth’s atmosphere, which leads to a pressure of 92 bar on the surface (1 bar is the pressure of the Earth’s atmosphere).
The dense atmosphere creates a strong greenhouse effect, resulting in temperatures of 462 degrees at the surface—higher than the melting point of lead, tin, and zinc. This makes it hotter than on Mercury, which is much closer to the sun, even though Venus receives only a quarter of the solar energy that reaches Mercury, and even though the outer layers of Venus’s atmosphere reflect a large part of the sunlight.
The high pressure at the surface transforms the carbon dioxide from its normal, gaseous state, into a supercritical fluid. The limit for this is 74 bar and 31 degrees, and both conditions are easily fulfilled on Venus. Supercritical CO2 covers Venus’s surface a bit like a planet-encompassing ocean. Its density, however, is much lower than that of water. Therefore, it would not feel like wading through water to someone wandering around in it. The supercritical fluid conducts heat very well, which helps to balance the temperature difference between day and night. It is, therefore, almost as hot on the dark side of Venus as it is on the bright side.
The structure of Venus’s atmosphere is also unusual. The troposphere extends upward from the ground to an elevation of about 65 kilometers, and makes up 99 percent of the atmosphere’s mass. There is almost no wind on the surface, but the upper parts of the troposphere travel at an enormous speed around the planet, essentially a constant super-hurricane with wind speeds of 360 km/h. Researchers call this ‘super-rotation’—the atmosphere only needs four Earth days to complete one rotation, while Venus’s rocky globe takes much longer. It’s as if Venus were swirling its cloak around its body very quickly, while spinning its body slowly.
The wind speeds differ depending on the geographic latitude. At the equator, the clouds rotate more slowly than in the mid-latitudes. Approaching the poles from the middle latitudes there are strong, very fast downdrafts, which are directed at the surface.
There are also weather patterns at the poles that we are not familiar with on Earth—'two-eyed cyclones’ with four times the force of the strongest storms on Earth. The storms have two eyes—centers of rotation—connected by an S-shaped band of clouds. Their other name is ‘polar dipoles.’
Earth-like conditions prevail in a zone that is part of the Venusian troposphere. At an altitude of 50 kilometers, the pressure is just one Earth atmosphere. The temperature drops at an altitude of 52 to 54 kilometers to 20 to 31 degrees. The spaceship in the novel, modeled on an actual NASA project, traveled in this zone. Because carbon dioxide is heavier than oxygen, a spaceship such as this one could be filled with oxygen for buoyancy, which could also be used as breathable air.
The mesosphere lies above the troposphere, extending from an altitude of 65 to 120 km. The thermosphere (120 to 350 km) rests atop the mesosphere. The clouds extend up to the lower mesosphere, where it is minus 43 degrees. Above that, it continues to get colder at first. The thermosphere, on the other hand, is cold on the night side (minus 173 degrees) and warm on the day side (27 to 127 degrees). In addition, an ionosphere forms on the day side in the mesosphere. The ionosphere is a layer with a high concentration of charged particles. On Earth, the ionosphere makes intercontinental radio communication possible.
At least three-quarters of the clouds are made up of numerous sulfuric acid droplets. It is due to these clouds that we see nothing of the surface of Venus. They reflect so much sunlight that it is only as bright on Venus’s surface as on a cloudy day on Earth. The sulfuric acid is formed when carbon dioxide, sulfur dioxide, and water vapor react in the presence of sunlight. However, this moisture doesn’t reach the surface. When it rains, the drops evaporate at a high altitude due to the heat.
There are occasional, unexplained storms in the cloud layer. Interestingly, researchers have observed numerous lightning flashes, but they hold differing theories regarding how these flashes originate, because the atmosphere should be too electrically conductive to allow lightning to form. Some researchers speculate that volcanic activity is the reason for the lightning.
The Surface: Venus’s skin
For a long time, due to Venus’s dense atmosphere, one could not directly view the surface. In the 1970s, the Russian Venera landers took the first photos of the surface, and in the early 1990s, NASA’s Magellan probe mapped 98 percent of the surface with a resolution of 120-300m (horizontal) by 30m (vertical). It turned out that gently undulating volcanic slopes cover 80 percent of Venus with differences in elevation of less than a thousand meters.
A small percentage of the surface consists of lowlands (up to 2 km below normal altitude), and an even smaller percentage of highlands (1.5 km above normal altitude). The difference in elevation from the lowest to the highest point of the Venusian surface is only 12 kilometers—on Earth, it is nearly 20 kilometers. Almost all formations have been given female names—the only exceptions are the Maxwell Montes and the Alpha and Beta Regio.
The two highlands correspond approximately to Earth’s continents. Aphrodite Terra is as big as South America and straddles the equator as part of the equatorial highland belt. Ishtar Terra lies between the 45th and the 80th latitude north and is about the size of Australia. It is where the 10,800-meter-high Maxwell Montes is located.
The plateau Lakshmi Planum is situated in the western part of Ishtar Terra. It is unusually flat by Venusian standards. It is about 4 kilometers high and is surrounded by several mountain chains that reach a height of up to 6.5 kilometers. These mountain chains look just like ‘fold mountains.’ However, no plate tectonics have been detected on Venus, so they are probably not folds. Perhaps the mountain chains arose due to volcanic folding directly beneath Ishtar Terra.
The summits of some Venusian mountains look bright in the radar image, as if covered by snow. However, the ‘snow’ is probably not frozen water, but the remnants of rainfall containing lead or bismuth sulfide. It rains lead—in the form of lead sulfide—on Venus.
The ‘cube world’ on Venus’s surface is also fascinating. The so-called tesserae consist of blocks that are each 20 kilom
eters wide, probably created by tectonic strain. The resulting faults intersect at almost right angles, creating the impression of tiles. Some tesserae rise directly from the lowlands.
Of course, Venus has a lot of old scars, i.e., meteorite craters. Only big chunks made it through the dense atmosphere. Therefore, its craters are wide. The largest, Mead, has a diameter of 270 kilometers. Larger craters, like those found on the moon, aren’t to be found here, probably because Venus’s crust is still relatively young due to its volcanic activity. Thus all traces of the ‘great bombardment’ during the early period of the solar system were erased.
Eighty-five percent of Venus’s surface is marked by volcanic activity. Scientists have counted well over 50,000 volcanic elevations. Some 167 volcanoes have a minimum diameter of 100 kilometers at their base. These volcanoes are conspicuous. The base of the 4.5-kilometer-high Theia Mons even has a diameter of 700 kilometers (the distance from Munich to Hanover, or New Orleans to Atlanta). It is thus wider than the highest volcano in our solar system, Olympus Mons on Mars. Like Venus’s highest volcano, Maat Mons, Theia Mons lies in the equatorial belt.
Why is Venus so active? Researchers suspect that the heat from the interior of the planet does not radiate continuously, as on Earth, but in surges. Venus’s volcanism is particularly intensive when there is a surge phase. There are currently signs of volcanic activity. For example, sudden increases in temperature on the surface, and increases in the percentage of sulfur dioxide in the atmosphere, have been measured.
The Clouds of Venus: Hard Science Fiction Page 29
