Its central star probably expanded into a red giant approximately 18 million years ago and in doing so swept away the planet’s atmosphere. This is what might happen to Earth a few billion years from now. The planet might have been engulfed by the atmosphere of its star at one time, but its rocky core survived, nevertheless.
WASP-12b
When WASP-12b was discovered in 2008, it ran counter to all expectations. Since then, it has been considered one of the hottest planets. It is more than 50 percent larger than Jupiter. But this Hot Jupiter is particularly interesting because it is being eaten alive. It orbits its sun so closely—one revolution takes 1.1 Earth days—that it probably loses 6 trillion kilos of mass every second, while its atmosphere is being blown away. It is assumed that the planet will die within 10 million years.
In addition, the planet might exhibit a high concentration of carbon in the form of carbon monoxide and methane. This means it could have a solid core containing a lot of diamond. Perhaps millions of years from now only a gigantic diamond will be left of WASP-12b. In addition, this planet was long considered the fastest-moving known planet. It moves at an impressive speed of 830,000 km/h.
Gliese 436 b
Gliese 436 b acts like a comet, because it drags a long tail behind itself. In its orbit, it seems to lose between 100 and 1,000 tons of hydrogen per second. It is assumed that during its existence Gliese 436 b has lost up to ten percent of its atmosphere. But its huge tail, which is approximately 50 times larger than the central star, obscures the sun during its orbit of less than three days.
There had been suggestions that planets with comet-like tails might exist, but Gliese 436 b was the first one actually discovered. Due to its size and proximity to its central star, it is called a Hot Neptune. Its gaseous tail might continue to exist for a longer period, because the sun that the planet orbits is a relatively cool red dwarf.
Janssen
On this world, one of the few with a real name, diamonds aren’t just a ‘girl’s best friend.’ Janssen, alias 55 Cancri e, is a Super-Earth and one of the five planets orbiting its star, the A component of the binary system Copernicus. We used to believe that a lot of water exists on 55 Cancri e. However, today researchers assume that the planet consists mainly of carbon in the form of graphite, diamond, and other minerals. An entire third of the planetary mass, about three times the mass of Earth, could be a single huge diamond.
Due to these findings, it is assumed that far-away rocky planets don’t have to be similar to Earth. They could be completely different, and Janssen was the first rocky planet to be detected that had a totally different composition than ours. On the day side, the planet reaches temperatures up to 2,400 degrees, while the night side is refreshingly cool with a maximum of 1,100 degrees.
HAT-P-1b
When astronomers discovered HAT-P-1b in 2006, they were amazed to find that it is almost twice the size of Jupiter, while weighing only half as much. Accordingly, its density is only a quarter of the density of water and it is lighter than cork. In a giant bathtub, it would float three times higher than Saturn. So far, nobody knows why this is the case. Perhaps additional heat reaches the interior of the planet, but there is also no explanation for that. One possibility is that the planet might be ‘lying on its side’ and rotating vertically to its orbit, like Uranus in our system. However, as this position is very rare, and other ‘bloated’ planets have already been discovered, this theory definitely does not apply to all of them. The planet’s star, by the way, is part of a binary system.
Gliese 1214 b
Gliese 1214 b is a Super-Earth. Its mass reaches almost 7 times that of Earth, and its radius is estimated to be more than two and a half Earth radii. It orbits its star at a distance of only 2 million kilometers. The most interesting aspect is that observations indicate its atmosphere consists mostly of water vapor.
The density of the planet might be around 2 grams per cubic centimeter. For comparison, that of Earth is 5.5 grams, and water weighs 1 gram per cubic centimeter. Scientists concluded that there must be lots of water there from the time the planet was farther away from its sun, in the habitable zone. The current close orbit and the high temperatures evaporate the water into a hot haze enveloping the planet. The planet is still considered one of the exoplanets most likely to have an ocean, but with a surface temperature of 120 to 280 degrees it would be so hot you’d better not jump into the water.
HD189733 b
The next time you stand in the rain, you might want to think of the inhabitants of HD 189733 b, even though it is rather unlikely they exist. On this planet there is not only a scorching temperature of 850 degrees, but perhaps also a rain of glass falling sideways, driven through the atmosphere by winds reaching up to 8,700 km/h. The cobalt blue color of the planet is not caused by oceans but by silicate particles in the clouds of its atmosphere. When these silicates condense in the extreme heat, they are turned into small drops of glass, which not only create the blue light, but are also carried around the planet by hurricanes. The planet is 30 times closer to its sun than Earth is to ours, and it has a captured rotation, meaning it always faces its star with the same side. The enormous temperature difference further reinforces the storms.
HD80606 b
All the planets in our solar system have relatively circular orbits, so that their closest and most distant points from the sun are not so different. The orbit of HD 80606 b, on the other hand, is strongly elliptical. During an orbit lasting 111 Earth days, the distance of HD 80606 b from its sun varies between 0.03 AU and 0.88 AU, where one astronomical unit equals the distance from the Earth to the sun. When it approaches the point closest to the sun, the temperature rises from 500 to 1,200 degrees within just six hours. Accordingly, the seasons on HD 80606 b are not determined by the angle of inclination but by its orbit. If you stayed high up in the atmosphere of the planet for one orbit, you would observe its star getting 30 times as large as the apparent size of our sun in our sky, while increasing its brightness by a factor of 1,000. The extreme temperature changes must create storms just as extreme, with winds blowing at 18,000 km/h.
TrES-2 b
Could there be a world that is darker than the color black? Of course! The best example is TrES-2 b, one of the darkest exoplanets discovered so far. It only reflects one percent of the incoming sunlight, but it glows in a dull red like a heating coil, because an extreme heat of more than 1,000 degrees exists there. TrES-2 is about 750 light years away from us, in the direction of the constellation Draco, and it orbits its star at a distance of only 5 million kilometers. Unlike Jupiter, this planet apparently has no reflective clouds that can repel sunlight—in Jupiter’s case, more than a third of it. Instead, it contains many light-absorbing chemicals that capture 99 percent of the radiation.
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Glossary of Acronyms
AGCT – Adenine, Guanine, Cytosine, Thymine (the base amino acids of DNA)
AI – Artificial Intelligence
ALMA – Atacama Large Millimeter Array
AU – Astronomical Unit (the distance from the Earth to the sun)
DNA – DeoxyriboNucleic Acid
E-ELT – European Extremely Large Telescope
ESO – European Southern Observatory
ISU – Independent Sensor Unit
IT – Information Technology
NASA – National Aeronautics and Space Administration
PMO – Planetary Mass Object, or Planemo
RNA – RiboNucleic Acid
UV – UltraViolet
VR – Virtual Reality
Metric to English Conversions
It is assumed that by the time the events of this novel take place, the United States will have joined the rest of the world and will be using the International System of Units, the modern form of the metric system.
Length:
centimeter = 0.39 inches
meter = 1.09 yards, or 3.28 feet
kilometer = 1093.61 yards, or 0.62 miles
Area:
square centimeter = 0.16 square inches
square meter = 1.20 square yards
square kilometer = 0.39 square miles
Weight:
gram = 0.04 ounces
kilogram = 35.27 ounces, or 2.20 pounds
Volume:
liter = 1.06 quarts, or 0.26 gallons
cubic meter = 35.31 cubic feet, or 1.31 cubic yards
Temperature:
To convert Celsius to Fahrenheit, multiply by 1.8 and then add 32
To convert Kelvin to Celsius, subtract 273.15
Excerpt: Proxima Dying
February 19, 19
They actually did it! Marchenko 2 shakes his head, but immediately rejects this human gesture. That ungrateful pack—they threw him out of his own base! And he had been so full of hope when he finally saw Adam and Eve again. My children! He had recognized them immediately, even though he had not seen them for 14 years. They had grown into beautiful children. What am I thinking? They aren’t children anymore, they’re grown-ups.
Marchenko 2 thought about it for a long time. Should he try to avenge this betrayal? Should he lie in wait for them when they leave the station? On the second day he stopped outside the range of all sensors, sat on the ocean floor, and pondered his options and strategies.
His hardware, the robot J, gives him freedom to endure. He can exist underwater for as long as he wants, because he has all the resources he needs. He is able to generate energy by using the temperature differences between various water levels. Using this energy, his fabricators can produce anything he needs to get along in this underwater world.
I have decided—I am going to accept their judgment… He is already on the way to the dark hemisphere of this planet, a planet that always faces its same sunburnt and hot side toward Proxima Centauri, its sun. The decision has not been easy for him. It might be interpreted as acceptance of the injustice done to him. That was the only reason he hesitated so long, because he obviously did not accept the verdict of his children. His children... When he thinks of them he feels the infinite love he had to suppress for so many years. He is not responsible for what happened, not he, because he is the victim.
It wasn’t easy sweeping away this argument, but finally a probabilistic analysis opened his eyes. He calculates which courses of action were open to Adam and Eve. He knows a lot about Proxima b, things that they have yet to find out. They are stupid—they should have disassembled his body in order to extract his knowledge. This would have saved them a lot of disappointment in the near future. But the knowledge he acquired over the years also tells him that Adam and Eve will inevitably venture into the dark hemisphere during their search for the former inhabitants of this planet. It is only a question of time, but he will see them again. If he gets going now, he will have a chance to thoroughly prepare for their arrival.
The ground ahead of him is sloping down slightly. The pressure sensors report a cool current moving towards the north-northwest. He scans the ocean floor with his searchlight. That is an old, deeply human habit. He does not need light to discover obstacles, but now and then he feels the need to see, just like he used to in his former life. He decided a long time ago to put away such behavioral patterns. They do not belong to him anymore. They are part of what he once was, a human being with all his shortcomings.
Today he is much more than that. He can be whatever he wants to be. For humans, that is a utopian idea and will always remain so. For him, it is a reality. During the first four years of his space voyage, he still believed he owed something to humans. But after the flare killed Adam and Eve, and the ship denied him a new start-up for the Adam and Eve project, he realized he owed humans no debt. He is alone, but that doesn’t matter: He can learn indefinitely, and his power is without limits. Still, he can clearly feel something is missing. The Creator has denied him the ability to create life, and it logically follows that his omnipotence is wasted if he has nobody to protect and to support with it. He needs Adam and Eve, and he knows they will come to him.
February 21, 19
“Shit! It’s cold!” Adam yells. The water level in Valkyrie sinks as fast as the bilge pumps can manage.
“Don’t make such a fuss,” Eve replies, already starting to take off her thin pressure suit.
I can easily understand Adam. Taking a short trip in Valkyrie is much too cumbersome. The battle with the other Marchenko—Marchenko 2—for the station set us back seriously in terms of technology. My robot body, J, still has not been completely repaired. We also haven’t yet had the time to upgrade Valkyrie with a real airlock, or at least with a coupling port to attach itself directly to the station, meaning Adam and Eve have to swim through cold water. While the suit-heating mechanism is working at its maximum, trying to keep them warm, water has a high thermal conductivity and the cold ocean quickly reduces their body heat.
The problem down here at the bottom of the sea is energy supply. The nano-fabricators can produce almost anything from practically any material, but they need the energy to do so. On the surface of the planet, the local sun— Proxima Centauri—provides more than enough energy, but the underwater station laboriously generates it from currents and the temperature differences between various water layers. That limits our options.
It is Eve’s fault we are starting our first excursion today, only a week after the dramatic conflict. She complained until I finally gave in. The two of them were not convinced by my counterargument that Marchenko 2 might have chosen to lurk nearby and, if so, I could not help them without J.
Our destination is the alien transmitter, the only trace left of the former inhabitants, as far as we know. It must have some function!
“Well, shall we go?” Eve is really in a hurry. Is this caused by curiosity, or by boredom with life at the bottom of the sea? She and Adam spent many years on board Messenger, which is very similar to the station down here. Marchenko 2 must have deliberately placed his ship here and then expanded it.
“Another 37 seconds,” I answer via the loudspeaker. “The pumps are almost finished.”
“And then?” Adam asks.
“We will have to see,” I say. “Eve is in charge today.”
Adam sits down in the seat near the stern end of the cabin and buckles himself in. Eve sits down as well and turns the monitor towards herself. She checks where the transmitter is shown on the map, but she doesn’t yet choose a course. Adam gives her a puzzled look, but she does not notice it. Then she reaches for the control levers to the right and left of the monitor. Valkyrie starts moving. For a few seconds a metallic scraping can be heard, until the vessel is far enough above the sea floor.
Eve does not seem to be taking the direct way. The small arrow on our screen indicates our direction of travel, and it points into areas we haven’t yet explored. At this depth there is eternal darkness anyways, which makes it hard for me to talk of a dark hemisphere.
“What would happen if we just keep going straight?” Adam wants to know.
“We know too little about that,” I reply. Yet the very question feels good. Columbus and his crewmates must likewise have agonized about that.
“Couldn’t it just go on forever? The hair plants on the bottom seem to have adapted to the environment.”
“We don’t know, though, whether the ocean covers the entire dark hemisphere. Perhaps there are gigantic mountain ranges there. Think of the Antarctic on Earth.”
Adam glares at me. “I don’t give a shit about Earth!”
“I just wanted to say that, on a certain planet in the solar system, the South Pole is not accessible by submarine, but the North Pole is.”
“I did understand,” Adam says, abruptly turning away. He doesn’t realize that this gesture is futile, because there is always a camera I can use to look at his face. But I better not rub his nose in
it.
“Stop arguing,” Eve says. She calmly focuses on the screen that shows the radar scan of the environment. “There are no discernible changes in the surface structure as far as the instruments reach… but that doesn’t mean anything.”
“Shouldn’t we start thinking about what to do next?” asks Adam with his head lowered. He has gotten out of his seat and is slowly pacing.
“Yes, Adam, I am setting course for the transmitter. Perhaps that will give us a clue.” Eve uses the right lever to control the thrust of the jets. I notice a force seeming to act on us from the outside, but it is really just our own inertia. Adam places a hand on the steel wall of the inner hull. The vessel changes its course.
While we approach our destination, Eve has the sensors checking in all wavelengths. The first measurement spike we detect is in the infrared range. The water temperature at the bottom is almost universally at four degrees. But on the monitor displaying infrared intensity, it looks as if, far away from us, somebody lit a candle in the dark. As I know more than the infrared sensor, namely the exact position of the object, I can calculate its emissions. This is definitely not a candle but rather a small heating plant. I try to match this with the image of the transmitter I remember, but that doesn’t work.
Proxima Rising Page 27