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Humankind has finally reached up and touched the sun–well, figuratively anyway, by means of NASA’s Parker solar probe. The spacecraft is the fastest human-created object ever made (so far) and travels at a blistering 532,000 kilometers per hour (330,000 mph). Since its launch in 2018, it has been circling closer and closer to the sun, and yesterday mission controllers announced that the craft had finally flown through the corona of the star (which can reach toasty temperatures of one million degrees Kelvin (1,800,000 degrees Fahrenheit)). Fortunately the upper atmosphere portion of the sun which the craft flew through was a mere 2500 degrees Fahrenheit and the crafts stout carbon shielding protected its sensitive instruments just fine.
During its time in the hot seat (which actually occurred back in April, but which is just being announced now), the Parker solar probe sampled solar particles and analyzed the sun’s magnetic fields so that scientists can try to understand more about the fundamental dynamics of stellar physics. The probe will continue to circle the sun during the course of its seven year mission and should provide ample material for physicists to analyze.
If you are like me, you yearn for the color-changing abilities of an octopus or a flamboyant cuttlefish. It’s going to be a long time before we have such capabilities ourselves, but surely technology can let us change the color of our surroundings and effects without repainting them. For a while now, the great laboratories and technology gurus have been promising us color-changing paint–where you walk into a room and turn a dial to change the wall color from green to pink to yellow to blue. I had a friend who shot some ads for GE who swore that this technology was about to hit markets (although since those ads were ten years ago, I am starting to have my doubts).
The Mood Ring!
What we do have is color changing chemicals which alter their tone based on temperature or light. The compounds that change color based on temperature were used for “mood-rings” back in my parents’ day. Then by the time I was a kid in the 80’s we had light-sensitive polymers.
Zartan, the ultra-mercenary
There was a GI Joe toy–Zartan the super mercenary–which was featured in a series of jaw-dropping animated commercials. In the ads, Zartan was a color-changing mercenary with super-ninja skills–a formidable chameleon of death! However the actual doll looked more like a middle-aged professional wrestler heading off to KISS night at Fire Island. Also Zartan did not change color very rapidly. One of my friends had the figurine and it engendered lots of dubious phrases like “look his arm is already turning a little bit gray….I’m sure of it.” Zartan’s legacy was not dissimilar from that of “The Diving Dolphin” a way to teach kids that ads do not necessarily reflect reality.
Anyway, all of this is to introduce the fact that I won a minor bet with my roommate! In a fog of victory, I jokingly asked for a jet (assuming that this was a way to permanently dismiss the subject) but she went online and bought me a super-awesome color-changing toy plane! It has been sitting next to me at the office as the seasons change and the Heating/Air-Conditioning goes haywire in various colleague-enraging ways. Here, therefore are actual photos of this astonishing color changing jet still in its original packaging.
Neutral Jet
The jet’s ambient color at neutral office temperatures is bright mauve. When the pilot flies his craft into the cold temperature of the upper atmosphere (or alternately, into the freezer next to the frozen peas) the plane turns dark puce and then dark brown!
Cold Jet
Flying out of the freezer, this experimental craft next landed on the sweltering environs atop of a huge mug of hot coffee. Soon the brown faded back to purple and then to blotchy magenta, and finally to pure US Air Force gray.
Hot Jet!
Mattel really outdid itself–this is a great toy! Zartan would be green with envy…eventually…well, maybe a little bit by his elbow? Let’s hope GE gets its act together so we can change our walls from bright magenta to gray to chocolate brown. That will be a future worth having!
Humankind is always fixating on the Moon and Mars as the most likely spots for the first space colonies, but there is another crazy possibility. Aside from the Sun and the Moon, Venus is the brightest object in the night sky. Earth’s closest planetary neighbor, Venus is a veritable sister planet with extremely similar mass and volume. Because of its size and position in the solar system, a great deal of early science fiction concentrated around Venus. Dreamers and fabulists posited that beneath its ominously uniform cloud cover was a lush tropical rainforest filled with lizard people and pulchritudinous scantily clad women (the fact that the planet’s Greco-Roman name is synonymous with the goddess of love and beauty seems to have influenced many generations of male space enthusiasts).
Maybe we should head over there and check it out…
Alas, the space age quickly dispensed with mankind’s sweaty-palmed fantasies about life on Venus. In 1970 the Soviet space probe, Venera 7, was the first spacecraft to successfully land on another planet (after a long series of earlier space probes were melted or crushed by atmospheric pressure). In the 23 minute window before the probe’s instruments failed, the craft recorded hellish extremes of temperature and pressure. The temperature on Venus’ surface averages around 500 °C (932 °F), (higher than the melting point of lead) and the pressure on the ground is equal to the pressure beneath a kilometer of earth’s ocean. The planet’s surface is a gloomy desertlike shell of slabs interspersed with weird volcanic features not found elsewhere in the solar system (which have strange names like “farra”,” novae”, and “arachnoids”). Additionally the broiling surface is scarred by huge impact craters, and intersected by immense volcanic mountains (the tallest of which looms 2 kilometers above Everest). The tops of these mountains are covered with a metallic snow made of elemental tellurium or lead sulfide (probably).
A photo of the surface of Venus from Venera 13
The atmosphere of Venus is a hellish fug of carbon dioxide which traps the sun’s energy in a self replicating greenhouse gone wrong. Above the dense clouds of CO2, the upper atmosphere is dominated by sulfur dioxide and corrosive sulfuric acid. Once Venus may have had water oceans and more earth-like conditions, but rampant greenhouse heating caused a feedback loop which caused the planet to become superheated billions of years ago. Without an magnetosphere, solar winds stripped Venus of its molecular hydrogen (yikes!).
Artist’s Impression of the Surface of Venus
Thus Venus does not initially present a very appealing picture for colonization! Yet the planet’s mass is similar to Earth (and humans’ long term viability in low gravity is far from certain). The planet is closer than Mars and windows of opportunity for travel are more frequent. Fifty kilometers (30 miles) above the surface of Venus, the temperature is stable between 0 and 50 degrees Celsius (32 to 122 degrees Fahrenheit). Light crafts filled with oxygen and nitrogen would float above the dense carbon dioxide. Today’s visionaries and dreamers therefore have stopped thinking of tropical jungles and envision instead a world of Aerostats and floating cities. Although the rotation of Venus is too slow to craft a space elevator, the flying colonists of Venus probably could build some sort of skyhook with existing or near future technology. Such a hook could be used to lift raw materials from the surface to manufacturing facilities in the skies. As more aerostat habitats were built, the colony would gain manufacturing strength, safety, and a greater ability to alter the barren world below (increasingly overshadowed by flying cities and hovering countries).
Imagine then a world like that of the Jetsons where the surface was unseen and not thought about (except by scientists and industrialists). Floating forests and croplands could be assembled to mimic earth habitats and provide resources for a bourgeoning population of Venusian humans. Skyships would cruise between the flying city states dotted jewel-like in the glowing heavens. Over time these flying habitats could be used to alter the planetary temperature and shield the desolate lands below. Humankind and whatever friends and stowaways came with us would finally have a second home in easy shouting distance of Earth. How long would it be then before we took steps to take Earth life even farther into the universe?
Discovered by Sir William Herschel in 1781, the seventh planet in our solar system is named for the Greek deity Uranus, the original skygod of the Greek cosmology. In classical myth Uranus was castrated and supplanted by his youngest son Cronus (Saturn) who then fell before Zeus (Jupiter) and indeed, the third largest planet in our solar system (in volume) is often overlooked by astronomers, whose eyes are trained on the dramatic gas-giants Jupiter and Saturn. Only one mission has flown by Uranus–Voyager II, which captured the following undramatic photo in 1986 as it whipped through on its way to Neptune.
Photograph of Uranus taken by Voyage II in 1986 (not a cue ball!)
All of this is a shame, Uranus is not only the first ice-giant planet but it is unique in the solar system for rotating vertically rather than horizontally (probably thanks to some apocalyptic super collision long ago in the planet’s history). From our perspective, the moons of Uranus orbit around it like a clock’s hands and its sporty red rings sometimes give it the appearance of a target. Uranus has an incredibly long rotation around the sun. One Uranus year equals 84 Earth years. Because it spins vertically rather than horizontally, one pole is cast in a super winter which lasts twenty of our earth years (remember the poles of Uranus are on the equator). Voyager flew by during the deep freeze of winter to get that boring photo up there, but now the seasons are changing and spring is coming to Uranus’ northern pole while fall is coming to the south (I wish there were a different name for the side poles—this is really confusing to write about).
Planet Uranus is seen in this composite image by the Keck II Telescope at near-infrared wavelengths. (Lawrence Sromovsky, UW-Madison Space Science and Engineering Center)
Because of the seasonal change, huge storms (the size of a continent on Earth) are tearing through the Uranian atmosphere with 500 kilometer-per-hour methane winds. Keep in mind that Uranus has the coldest atmosphere in the solar system, probably because the collision which knocked it on its side dissipated its primordial heat (although nobody really knows). Temperatures there get down to a chilly –224 °C. Brrr!
A similar bright spot photographed by Hubbel in 2005 just before the vernal equinox
The spring storms are apparently dramatic and fierce enough to be seen from Earth. Yesterday astronomers reported the appearance of a huge white speck with an albedo ten times that of the planet. This methane storm probably looks like an immense immense thundercloud spreading above the usually placid blue cloud cover of the ice world. Saturn has been going through its own cycle of super storms recently (in addition to the great hexagonal storm raging on its north pole). Its tempting to adapt the folksy mannerisms of country smalltalk and suggest that weather in the solar system has been bad lately–but humankind is probably only just now able to apprehend such phenomena!
The Eocene (Illustration by Bob Hynes for the Smithsonian Institution)
The Eocene epoch (which lasted from 56 million ago to 34 million years ago) was hot! Temperate forests ran all the way to the poles. Steamy tropical jungles grew in the latitude where Maine is now and the equatorial regions of earth were (probably) sweltering. Tropical reefs formed in the coastal waters around a heavily forested and ice-free Antarctica. Since there was not year-round ice at each pole, the sea levels were much higher.
A Global Map of the Early Eocene (map by Dr. Ron Blakey)
The Eocene was a time when most of the contemporary mammalian orders first appeared. The earliest artiodactyls, perissodactyls, rodents, bats, probiscideans, sirenians, and primates all originated during this time. Of course mammals were not the only story: the Eocene was also a time of great diversification for birds and many familiar orders of avians developed then. Reptiles begin to put the setbacks which marked the end of the Cretaceous behind them and several giant new species emerged including an immense tropical ur-python and a host of crocodiles and turtles. It is harrowing to think that the first wee dawn horses and cute little early atiodactyls were forced to contend with a 13 meter long super snakes and giant crocodilians (which flourished in the great hot swamps of Alaska), but such is the case.
Titanboa with Ancient Crocodilian (painting by Jason Bourque)
The high temperatures of the Eocene are perplexing to scientists. By contrast, the temperatures of the Paleocene (which was the first era of the Cenezoic and had directly preceded the Eocene) were much more temperate. In fact the temperature spike of 56 million years ago seems to have ended the Paleocene and brought about the diversification of Eocene life. The rapid warming is known as the Palaeocene-Eocene thermal maximum and scientists have been vigorously debating what caused the climate change. An immense amount of carbon seems to have entered the atmosphere at this time, which in turn led to greenhouse warming. It remains controversial as to how such a large quantity of carbon got into the atmosphere. Comet/meteorite impact, massive peat fires, and volcanic activity have been suggested as triggers, however supporting evidence is lacking. The release of globally significant quantities of hydrocarbons–which had been trapped in undersea clathrates seems like a more feasible hypothesis, as does the idea that the earth’s orbit brought the planet closer to the sun for a time.
Phenacodus, a goat-sized grazer of the Eocene era (painting by Heinrich Harder)
The end of the Eocene was also linked to the carbon cycle. Reduced carbon dioxide in the atmosphere seems to have led to global cooling and newly evolved varieties of grasses began to invade large swaths of the world. Additionally two massive meteor strikes in Siberia and Maryland combined with substantial volcanic activity to finish off the long hot summer. But during the Oligocene, the era which followed the Eocene, the world was a much more familiar place inhabited by orders of animals which are still here with us today (or are us–since primates first evolved during the Eocene).
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