The Surface Of Mirkheim

Copied from Poul Anderson Appreciation, 20 June 2013.

Mirkheim, the supermetal-coated remnant of a giant planet of a massive star that went supernova, is unlit by any sun so might resemble a rogue planet except that its surface is:

not covered by dust or frozen atmosphere;

 
not cratered;

metallic, hard, blank, dimly shining, almost mirror-like;

in some places, fantastically ridged and corrugated by congealed moltenness;

with five Terrestrial gravities and enough radioactivity to kill in weeks.

Rogue planets, which feature in more than one work by Anderson, are sunless because they move through interstellar space. Mirkheim, which appears in a short story and a novel, is sunless because its sun exploded a long time ago. Sunlessness suggests sameness but Anderson takes the trouble to imagine the differences, as summarized above.

Shortly before Sandra Tamarin visits Mirkheim, David Falkayn has visited the sub-Jovian Babur. Thus, although Anderson describes many beautiful humanly colonized planets like Hermes, Avalon and Dennitza, he also envisages planetary surfaces that are as inhospitable as space itself and also shows us what his characters see when they explore such places.

Living beings venture to Mirkheim not to live there but to mine the supermetals which are so valuable that a war is fought over them.

The Mystery Of Mirkheim

The following propositions are facts within Poul Anderson's History of Technic Civilization:

planetary systems do not condense around giant stars;

Beta Centauri is a giant star with planets because, while it was condensing, its nebula retarded, then captured, a group of rogue planets;

van Rijn says somewhere that scientists are still trying to figure out how the red giant Betelgeuse has planets;

Mirkheim was a planet of fifteen hundred Terrestrial masses orbiting a star as bright as a hundred Sols.

So how did Mirkheim exist? We are told how it was found:

"From the known distribution of former supernovae, together with data on other star types, dust, gas, radiation, magnetism, present location and concentrations, the time derivatives of these quantities: using well-established theories of galactic development, it is possible to compute with reasonable probability the distribution of undiscovered dark giants within a radius of a few hundred parsecs....The most you can learn is the likelihood (not the certainty) of a given type of object existing within such-and-such a distance of yourself, and the likeliest (not the indubitable) direction."
-Poul Anderson, David Falkayn: Star Trader (New York, 2010), p. 653.

But the "...given type of object..." has to be possible, however improbable, in the first place. Surely Astrocenter would not have been able to compute the probability of a condensing giant star capturing several rogue planets? So how was Mirkheim's probability computed?

At Mirkheim And Its Sun

Copied from Poul Anderson Appreciation, 13 Jan '15:

What sun? It exploded. Yes. However, a nova or supernova always leaves a remnant. Mirkheim is the remnant, the blasted core, of a companion planet too large to have been entirely vaporized or disintegrated by the stellar explosion. Similarly, the supernova itself left a remnant, imperceptibly shrinking towards black hole status. Thus, two unusual heavenly bodies still orbit in close proximity. Coya Conyon says that they had originated as a double stellar system, not as a star with a planetary system.

The stellar remnant is six Solar masses compressed into one Terrestrial volume. Therefore, it "...has stupendous gravitational power..." (David Falkayn: Star Trader, p. 676) which warps space so that "...the laws of nature take on an eerie aspect." (ibid.) Anderson does not elaborate although readers of popular science and science fiction have learned that spatial distortions affect time and matter in counter-intuitive ways described by Einstein, not by Newton or by common sense. (Common sense generalizes our experience on a macroscopic scale but at sub-relativistic velocities.)

Secondly, the fantastically rapid spin of a dwarf star also "...generates relativistic forces, describable only if you have determined the precise quantities involved." (ibid.) Thirdly (I think that this is a separate point), pulsations usually found only inside atomic nuclei stretch across interplanetary distances. Fourthly, as with any star, there is radiation although this is comparatively easy to guard against, dim visible light but lurid gamma and X-rays.

The Ythrian spaceship, Dewfall, chartered by Nicholas van Rijn, finds the sun - so small as to be undetectable except within a few parsecs but van Rijn had known where to look. Maximum photoamplification reveals a white spark but makes other stars painfully brilliant. Expensive equipment installed by van Rijn detects the light-bending due to a sub-stellar object between forty and fifty astronomical units from the star. To establish its position, they need a long baseline which would take weeks at sublight speeds. However, Dewfall's engines are well-tuned enough to use hyperdrive even this deep in a gravity well.

As Dewfall approaches Mirkheim, three Supermetals warships move to intercept and block escape. The Ythrian ship's approach has been observed. Relative speeds and distances are such that one ship can engage until the others arrive. They intend to detain crew and passengers but will fire if Dewfall attempts to escape. Having come prepared, van Rijn takes charge and accelerates on negagrav back towards the sun. No enemy missiles can accelerate fast enough "...to get past defensive fire..." (p. 675) Dewfall goes hyper, though not at full speed, and reverts to normal state when nearly at the sun but still continues toward, then around, it. Prior computations ordered by van Rijn and readings taken by Coya as they approached the sun are in the data banks. Now Coya inserts current data that enable van Rijn and Hirharouk to steer. Commodore Nadi of Supermetals can neither pursue nor predict where his enemy will emerge.

The Ythrian beats his wings while the man kneels in prayer. They must cope with a meteoroid swarm and a plasma cloud but:

"They won past reef and riptide..." (p. 677)

I have found it rewarding to summarize other battles in space. See here and here.

Hermes

Originally published on Poul Anderson Appreciation, 21 April 2012.

The planet Hermes:

is in the system of the star Maia in Sector Antares;

has 97% G;

has two moons, Caduceus and Sandalion;

has one large continent, Greatland, with an arid interior;

was colonized early mainly by northern Europeans;

was developed by private corporations which became the basis of the Hermetian state;

began as a Grand Duchy with a stratified society;

gained stewardship of the industrially valuable planet Mirkheim after the Babur War;

at that time also became an ordinary crowned republic while remaining nominally a Grand Duchy;

during the Troubles, developed a military-oriented society with authority concentrated in the executive and rule by whoever commanded the greatest armed force;

lost Mirkheim when Hans Molitor became Emperor;

rioted against forced demilitarization under Molitor and was pacified by the Marines;

prospered under Grand Duke Edwin Cairncross who reclaimed the interior with canals, landscaping, imported species, urbanization, commerce and a castle on an extinct volcano.

Greatland divides the Auroral Ocean to the east from the Corybantic Ocean to the west. The city of Starfall is on the east coast where the Palomino River flows into Daybreak Bay. Tilirras sing from millionleafs and there are colorfully winged, trilling nidifexes.

When Hermes declared independence from Terra, its new constitution recognized the Kindred as the Thousand Families controlling the "domains": either landed estates or corporations. The presidents of the domains elect the Duke or Duchess of Hermes from the Tamarin family which must not own a domain. Ancestors of Kindred and Tamarins were the first to arrive from Earth but, instead of founding a corporation, the Tamarins free lanced as scientists etc. "Followers," holding entailed shares, are junior partners in domains, each holding a single vote in domain affairs whereas Kindred have ten. "Travers," hirelings or unaffiliated business people, descended from latecomers, are not taxed and have no vote. The Liberation Front demands full rights for Travers who, as a result of "Libby" campaigns, gain a vote in choosing municipal officers. Travers bow to the Duchess, Followers salute, Kindred shake hands.

The Asmundsens, Followers of the Runebergs and tenants on the Brightwater estate, manage the Runeberg's copper industry. A younger Asmundsen, who explores and develops other planets in the Maian system, is obliged by custom to give preferential promotions to fellow Followers but acknowledges that his strike-threatening Traver employees have legitimate grievances which he tries to address by negotiating in person with their leaders and offering compensations like extra vacations. Hornbeck, the estate of the Falkayn domain, is on a plateau jutting from Mount Nevis in the Thunderhead Mountains. Sam Romney, independent ship-owner, fisherman and loyal Traver, does most of his business with the Falkayns. 

Baburite invaders appoint Benoni Strang, an embittered Traver, as High Commissioner for Hermes. Strang, as Bayard Story of the Galactic Developments company and the Seven in Space cartel, had secretly armed Babur. As Commissioner, he intends to impose a social revolution, democratizing the domains and obliging them to conduct all operations through a central trade authority. Through Duchess Sandra Tamarin-Asmundsen, he announces that a Grand Assembly to draft a new constitution, as provided for in the existing constitution, will be held when procedures for the election of delegates are in place. Christa Broderick, the Liberation Front leader welcomes Strang's proposed social reforms but Strang bypasses the Front, many of whom oppose the invasion, and his Traver supporters form a new party.

Broderick's city and farming Followers snipe and sabotage while guerrillas operate in the Arcadian Hills and the Thunderheads. Both groups attack Starfall while the returned Ducal Space Navy engages orbiting Baburite craft. After the liberation, the Duchess receives a petition. Revolutionary terror has weakened the domains and the Liberation Front has gained confidence. It is agreed that a constitutional convention must await a firm peace but then Hermes, while remaining nominally a duchy, will become in practice a republic. Later, Cairncross is not a Tamarin though he is remotely descended from the Founder of the Empire, Manuel Argos.

Hermes, like Avalon, Aeneas and Vixen, is an entire inhabited planet imagined in detail by Poul Anderson.

Sources: Mirkheim and A Stone In Heaven.

Unusual Heavenly Bodies

Originally published on Poul Anderson Appreciation, 21 April 2012.

In Poul Anderson's History of Technic Civilization:

Planets

Jupiter has solid land masses because that was a reasonable assumption when Anderson wrote about it.
Diomedes' poles are in the ecliptic plane. Each spends half the year in winter and night. Intelligent Diomedeans are winged migrators.
Although the planet Woden has two and a half Terran gravities, its sun is so energetic that Wodenite life can grow massive.
Tidal action has forced one hemisphere of the small, eccentrically orbiting, librating planet Ikrananka to face its red dwarf sun but such slow rotation generates a weak magnetic field so that the planet retains an atmosphere although most of its water has frozen on the cold side making the warm side a slowly deteriorating desert whose inhabitants, struggling for survival in their season-less, rhythm-less environment, regard nature as hostile, believing in demons but not in gods, whereas dwellers on the edge of the Twilight Zone with rain, snow, day, night and constellations, more conventionally believe in an annually dying and rising god and a single devil whose power can be neutralized. The latter are easier to trade with.
Pressure and temperature gradients on Daedalus refract light around the curve of the planet so that there is no horizon. Sunset is a ring of fire.
Nike is very small but holds an atmosphere and biosphere because it is so old that its weak gravity has had enough time to pull heavier elements into an atmosphere-generating solid core. Age explains its sun's variability which adversely affects Nikean weather.

Giant Stars and Rogue Planets

The red giant Betelgeuse has planets, some of them with life, because that was a reasonable assumption when Anderson wrote about it.
David Falkayn brags of finding a rogue (sunless) planet between Tau Ceti and 70 Ophiuchi although this adventure really happened to someone else.
The Merseians keep a base on Vorida, a rogue planet in the Betelgeuse sector.
The rogue planet Satan bypassing the blue giant Beta Crucis in a hyperbolic orbit becomes a base for the industrially valuable transformation of elements into heavier isotopes when its cryosphere becomes atmosphere and hydrosphere, coolants for heat waste.
A condensing giant star's gravity prevents the condensation of planets but nebular friction around the condensing blue giant Beta Centauri converted the hyperbolic orbits of a cluster of passing rogue planets into eccentric elliptical orbits.
A rogue planet hitting the star Saxo causes it to explode destroying its planets, including the inhabited Starkad.

Giant Planets and Eccentric Orbits

The captured planets of the blue giant Beta Centauri have eccentric orbits. See above.
Another star passing near Siekh skews its planets' orbits. The planet Talwin's distance from Siekh varies from 0.87 to 2.62 astronomical units. Huge ice caps form and melt each twice Terran year. There are floods and rain storms. One intelligent race hibernates in caves. Another estivates at sea. They do not meet.
In the Cerulian system, resonance with the jovoid planet Ogre has multiplied perturbation and brought the eccentricity of the terrestroid Vixen's orbit close to one-half so that, with a 24 degree axial tilt and midsummer nearly at periastron, once every eighteen month year the northern hemisphere is scorched with four times the radiation that Terra receives from Sol - snow melts, rivers overflow, lakes bake dry, storms rage, fires break out, erosion prevents mountain formation, hot wind blows dust and ash across dry plains.
A subjovian planet, which lost most of its lighter gasses when an eccentrically orbiting moon crashed on it, now has 15 Terran masses concentrated in a solid globe called Paradox but 8% of its atmosphere remains helium which diffuses through any material, ruining unprotected equipment.
The Cloud Universe globular cluster's eccentric orbit passes through dense clouds near the galactic center, gathering gas and dust which condense into heavy-metal-rich stars and planets.

Supernovae

When a superjovian planet of 1500 terrestrial masses orbits a star that goes supernova, the planetary core, now called Mirkheim, survives coated in valuable supermetals which are impossibly expensive to synthesise.
The massive star Valenderay, older than normal for its type in its region, must have come from elsewhere. Its supernova explosion will cause ecological disaster on the planet Merseia a parsec away unless artificial force screens protect the planet.
A nearby supernova causes a superjovian planet of 3000 Terrestrial masses to lose all its hydrogen and helium, over 90% of its mass, transforming it into Ramnu, a glacial globe of 310 Terrestrial masses, later inhabited by small, intelligent gliders.
A peak of radiation from the planet Dathyna's massive, metal-rich, irregularly variable sun, which probably condensed near a recent supernova, destroyed civilization but produced a killer mutation which exterminated the parent race, appropriated its technology and now threatens the Polesotechnic League.
Periodic ingestion of new matter by the Cloud Universe (see above) causes several supernovae per century for at least a million years.

Notes on the Above

Falkayn spells out why Satan alone is ideal for producing heavier isotopes. This cannot be done:

on inhabited planets because heat and radioactive waste would make them uninhabitable;
on uninhabited planets because heat waste added to solar radiation would vaporize the rivers needed for coolants;
on uninhabited planets with orbiting albedo-raising dust clouds because these would trap home-grown heat;
in newly formed systems because factories would be bombarded by meteors and asteroids;
on airless planets because the necessary heat exchangers are expensive and put engineering limits on the size of a plant;
on Jovoid planets because free hydrogen diffuses through materials and interferes with nuclear reactions;
on ordinary rogue planets because temperatures near absolute zero affect the properties of matter and because liquid water and gaseous atmosphere are necessary coolants.
 

Anderson invented several ways to disrupt familiar celestial processes:

a giant star capturing rogue planets;
a supernova transforming one of its own planets into the industrially valuable Mirkheim;
a supernova potentially devastating a planet in a nearby system;
a supernova transforming a planet in a nearby system into the massive but solid Ramnu;
a supernova affecting the condensation of another star;
a rogue planet causing a nova by hitting a star;
a rogue planet becoming the industrially valuable Satan by just missing a star;
a star causing eccentric planetary orbits by just missing another star;
an eccentrically orbiting moon transforming its planet into the massive but solid Paradox by hitting it;
an eccentrically orbiting globular cluster causing new stellar condensations and novae by gathering dust from clouds near the galactic center;
planets with eccentric axial tilts;
a planet with no horizon;
a planet with a very close horizon!

Unscientific readers forget technical details so it is good to summarize them. The explanations begin to sound similar but, in each case, they are used to create a unique effect. Supernovae:

usually destroy all their own planets;
can affect planets in nearby systems;
possibly affected the condensation of a nearby star. 
 

In "A Sun Invisible," Anderson planned to introduce the unexpected Beta Centaurian system as the solution of a puzzle so he had Falkayn mention rogue planets earlier in the story. Thus, it was not a deus ex machina when captured rogues turned out to explain why there are planets orbiting a giant star. In Ensign Flandry, Anderson introduced the planet Starkad only to reveal, near the end of the novel, that its sun was doomed to be hit by a rogue planet so, again, Anderson made sure that a rogue, Vorida, had been mentioned much earlier in the novel.
 

These features recur:
 

giant stars;
superjovian planets;
novae and supernovae;
industrially valuable planets;
massive but solid planets;
stellar and planetary condensations;
metal-rich stars and planets;
rogue planets;
collisions;
near misses;
eccentric orbits;
other odd planets;
intelligent fliers or gliders.

Responding to these phenomena, Anderson's characters:

negotiate with Ikranankans and Betelgeuseans;
let extra-solar hydrogen-breathers who have colonized Ogre colonize Jupiter;
colonize the Beta Centaurian system;
trade with Diomedeans;
save Merseia;
incorporate Wodenites and Dathynans;
evacuate some Starkadians;
exploit Satan, Mirkheim and the Cloud Universe;
study Talwin, Ramnu and Paradox;
live on Kirkasant (in the Cloud Universe), Vixen, Daedalus and Nike.

Added on 12/5/12: A revised text explains that the Betelguesean planets were seeded and colonized but should they have existed? 

Added, 23/5/12: Data on Diomedes that I missed above: the system is metal-poor though not old possibly because the electromagnetic action of a passing neutron star fractionalized the original cloud of dust and gas. Consequently, Diomedes has 4.75 terrestrial mass but a low density so its gravity is only 1.10.

An Inhabited Mirkheim!

Originally published on Poul Anderson Appreciation, 3 Dec 2013.

In Poul Anderson's and Gordon R Dickson's Hoka (New York, 1985), a nearby supernova blew away the atmosphere of a superjovian planet and covered its solidified core with heavy elements, including radioactives. This is familiar Anderson territory, a cosmic accident with an unlikely but nevertheless possible outcome.

It is also the planet Mirkheim revisited but with one big difference: life, taking energy from local radioactive material "...rather than the feeble red sun." (p. 174) Animals eat isotopes concentrated by plants. A Brobingnagian (for such is the human name of the planet) does not oxidize organic materials, "...like most creatures in known space..." (ibid.), but fissions nuclei and is correspondingly strong.

His internal processes produce little radiation which is, in any case, absorbed by his stomach but he must take precautions when disposing of body wastes. Brobdingnagians, evolved on an airless planet, have neither nose nor ears and instead communicate by transmitting and receiving vibrations through the ground via tympani on their meter-long feet. The large round head and body are covered by blue fur and the brown eyes are bone dry.

How much of this is serious scientific speculation and how much is comical exaggeration in keeping with the comedy of the rest of the Hoka series? 

Living In The Galaxy

Originally published on Poul Anderson Appreciation, 21 April 2012.

After five thousand years of interstellar travel, mankind has thinly occupied parts of two or three spiral arms. Old Earth, still called Home, is a half remembered myth in another spiral arm. Daven Laure, from the Fireland mountains on New Vixen, has never seen Earth, has never met anyone who has seen Earth and has no family record of any ancestor who had seen Earth. As a Ranger of the Commonalty, he trained at Starborough near Irontower City on Aladir, travels in a ship with a consciousness level computer and encounters nonhuman sophonts. The Commonalty, a service organisation, not a government, has members on an estimated ten million planets but:

"We know that other branches of humanity have their distinctive ways, and hear rumors of yet stranger ones." (1) 

The colonized planet Serieve, poor in heavy metals, is close to the northern verge of its spiral arm with only the galactic halo of scattered ancient globular clusters and a very thin interstellar medium beyond it. The only concentration of gas and dust in the region, the Dragon's Head Nebula, is in transit. New colonists of an entire planet usually build low but the Serievans have built a high rise industrial city, Pelogard, on an arctic island where they can extract minerals from ocean currents. Flocks of blue, winged, bird-like organisms circle above trees with fronded silver leaves.

Several interlocking narratives of the Technic History conclude in the Commonalty period:

(i) Terrans colonized Aeneas;
Dominic Flandry of Terra exiled Aenean rebels;
the rebels colonized Kirkasant hidden in the "Cloud Universe" global cluster;
a ship from Kirkasant made an epic journey to the colony planet Serieve.

(ii) Terrans colonized Hermes and Vixen;
David Falkayn of Hermes discovered the industrially valuable planet Mirkheim and initiated the Supermetals company to exploit it;
Henry Kittredge of Vixen was the Supermetals ground operations chief on Mirkheim;
the Vixenite share in Supermetals bought badly needed weather stations;
Flandry and Catherine Kittredge of the Vixenite weather engineering department successfully resisted alien invasion of Vixen, at one stage hiding in a weather station.

(iii) Helen Kitteridge of Vixen, Terran Space Navy energy weapons controller, joined Olaf Magnusson's revolt;
intelligence gathered by Flandry's daughter brought down Magnusson.

(iv) Vixenites colonized New Vixen;
Daven Laure of New Vixen integrated Kirkasanters into interstellar civilization after a ship from Kirkasant had reached Serieve.

These interlocking narratives touch on the histories of several planets and highlight eight individuals: three Vixenite Kittredges, three major figures - Falkayn, Flandry and Magnusson - and two others, Flandry's daughter and Daven Laure. As with the history of the Ythrians (see here), we would like to know more but this was all that Anderson had space to tell us.

Beyond the Dragon's Head is unexplored space. Directly behind this Nebula is the "Cloud Universe" globular cluster. A globular cluster comprises old, red, metal-poor stars in a nearly perfect vacuum. However, the Cloud Universe's eccentric orbit passes through dense clouds of gas and dust near the galactic center. The cluster gravitationally gathers gas which makes it opaque and condenses into new stars. Periodic ingestion of new matter causes several supernovae per century for at least a million years. Stars are unstable and radiation levels prevent any life in the center of the cluster. From within the Cloud Universe, space appears as neither dark nor empty but as bright and star-filled. Stars are light months apart.

A fleet fled from the Terran Empire. One ship fled as far as possible, a quarter way round the galaxy through two spiral arms, and hid as well as possible, on Kirkasant in the Cloud Universe. Such a long trip in an early vessel required frequent repair, resupply and refilling of nuclear converters. On arrival, the ship needed a rebuild but the Kirkasanters, as they now were, needed five millennia to build the industrial capacity for interplanetary travel. High radiation and a harsh environment hastened evolution. The first generation mined and forged metal. The second supported a literate class. When scientific method was rediscovered, relativity theory, based on observations from within the Cloud Universe, implied a universe two or three hundred light years across with space tightly curved by the concentrated mass. The Kirkasanters progressed from moon rockets to hyperdrive in a single lifetime. They knew it was possible and were guided by old texts and the hulk of the ancestral ship.

The first interstellar ships visited stars visible from home. The Makt crew went further, believing that they would be able to steer home by already charted stars. However, because of the haze and shine in the Cloud Universe, absolute magnitudes and therefore relative distances had not been calculated accurately. Bypassing home space, the ship became lost in the Cloud until it exited the cluster. Theory implied that they had made a dimensional crossing into another universe, even though each universe was visible from the other. Legendary references to space as dark suggested that the ancestors had come from here. When they had re-entered the cluster three times to no avail, telescopes revealed a distant black cloud (the Dragon's Head). Reasoning that the ancestors, fleeing an enemy, might have passed through such a cloud, the Makt crew approached and traversed the Nebula. Then they used neutrino detectors to find the nuclear power plants of an advanced civilization and, nearly out of fuel, reached Serieve.

Entering the Cloud Universe, Jaccavrie (Laure's ship) and Makt could not find Kirkasant and were in danger from radiation, hidden bodies and unpredictable stellar processes. Laure explored several planets both to confirm that they were rich in heavy metals and to establish a claim of ownership for himself and the Makt crew. When miners swarm into the cluster, the Kirkasanters will be rich and the miners' beacons will enable them to map the cluster and find their planet: a neat solution to a technical problem.

That the Kirkasanters were descended from the Aeneans is a reasonable inference given that Anderson did not write anything further to contradict it. It is certainly unlikely that any other human group fled that far that early.

Thus, Anderson constructed an sf story about:

vast interstellar distances albeit traversed by hyperdrive;
unusual celestial bodies and processes;
human communities isolated for millennia in different environments, thus becoming distinct species;
no nonhuman intelligences in this story although they are mentioned once;
no interstellar empires although they had existed earlier in this fictitious history;
a new form of interstellar organization meriting further discussion.

Poul Anderson, "Starfog" IN Anderson, The Long Night, New York, 1983, pp. 242-310, AT p. 248.

Cynthia And Woden

Cynthia
"Oh, treetop highways under the golden-red sun of Cynthia!"
-Poul Anderson, "How To Be Ethnic In One Easy Lesson" IN Anderson, The Van Rijn Method (Riverdale, NY, 2009), pp. 175-197 AT p. 183.

"Oh, to be back on Ta-chih-chien-pi, Lifehome-under-Sky, again in a treetop house among forest perfumes!"
-Poul Anderson, "The Trouble Twisters" IN Anderson, David Falkayn: Star Trader (Riverdale, NY, 2010), pp. 77-208 AT VI, p. 138.

"Ta-chih-chien-pi - 02 Eridani A II or Cynthia to humans - felt even more distant than it was, warm ruddy sunlight and rustling leaves around treetop homes lost in time as well as space."
-Poul Anderson, "Day of Burning" IN David Falkayn: Star Trader, pp. 209-272 AT pp. 224-225.

"'Light across a sea of leaves, but down below full of shapes and mysteries, a cry of color on wings and petals, a glen where a rill comes joyful -...'"
-Poul Anderson, Mirkheim IN Anderson, Rise Of The Terran Empire (Riverdale, NY, 2011), pp. 1-291 AT XXI, p. 289.

Woden
"Adzel's thoughts turned sentimentally back to Woden, the dear broad plains under the brilliant sun, where his hooves spurned kilometers..."
"The Trouble Twisters," V, p. 132.

"'That wild bright openness where the winds run loose, horizons endlessly before us but also flowers underfoot, a land that that is the living Nirvana -...'"
-Mirkheim, p. 289.

I will quote more about either planet if I find it.

Dark Satanic Mills

Ten years after passing Beta Crucis, Satan should have (many unknown, remember) calmed down:

it will no longer be illuminated any more than inhabited planets;

the cold, exposed rocks will have absorbed any excess heat that has not been re-radiated;

temperature will be tolerable and decreasing steadily though not rapidly;

 industry will be able to build;

heat output will be balanced with loss;

the atmosphere will be poisonous and most jobs will be automated so radioactive waste will be unproblematic;

the surface will be warm, lit by stars and lamps;

radio beacons will guide cargo shuttles;

there will be nuclear conversion units everywhere;

tons of formerly rare materials will be exported daily;

hopefully, SSL will monopolize the sale of franchises;

there will be both great wealth and great war potential as later with Mirkheim which Falkayn will seek, find and not hand over to van Rijn.

Moving Planets

"Men can alter a world, or ruin one; but they cannot move it one centimeter off its ordained course. That requires energies of literally cosmic magnitude.
"So you couldn't ease this planet into a suitable orbit around Beta Crucis. It must continue its endless wanderings."
-Poul Anderson, Satan's World IN Anderson, David Falkayn: Star Trader (Riverdale, NY, 2010), pp. 329-598 AT p. 357.

Would gravity control not allow the moving of planets? In James Blish's Cities In Flight, men move a planet between galaxies faster than light with graviton polarity generators. In Olaf Stapledon's Star Maker, the telepathic galactic mind launches a star cluster between galaxies.

Satan, the planet passing close to Beta Crucis, is a rogue. It seems that Anderson is correct when he tells us that there are many such planets. Satan's cryosphere becomes atmosphere and hydrosphere at periastron passage but re-forms during recession.

"'Nothing basic would have happened.'"
-op. cit., p. 356.

- except that the planet can be put to massive industrial use while it is energized. Satan and Mirkheim are two amazing creations by Anderson and the latter idea was suggested by his editor, John W. Campbell.

The Center Of The Cloud Universe

Copied from Poul Appreciation Appreciation, 4 May 2014.

Poul Anderson, "Starfog" IN Anderson, Flandry's Legacy (New York, 2012), pp. 709-794. 

The "Cloud Universe" in Poul Anderson's "Starfog" is simultaneously both a globular cluster and a gaseous nebula. I have tried to convey the richness of Anderson's imagination by summarizing his accounts of this spatial environment but there is always more. The accounts permeate the narrative rather than being confined to an introductory passage.

At the center:

nebular gas and dust are so dense that they present "...a nearly featureless glow..." (p. 772);
the glow is pearl-colored, with rainbows;
the stars are so close that thousands are visible despite the "starfog";
the plasma is actively energetic;
denser clouds conceal hazards - drifts of dust, rogue planets and dead stars;
the hazards, "...more than fog...," are compared to "...shoals, reefs, and riptides" (ibid.);
the two exploratory spacecraft are compared to "...frigates on unknown seas of ancient Earth..." (ibid.), but this sea is not flat and has no horizon;
gas and dust are so gravitationally concentrated that there is an unbelievable rate of star-production;
every time the cluster gathers material from the clouds of the galactic center, there are several supernovae per century for at least a million years;
radiation has sterilized every planet within a fifty light year radius;
atoms have been through a dozen supernova explosions, far more than elsewhere;
giant planets do not have shells of frozen water and smaller ones do not have silicate crusts;
iron, gold, mercury, tungsten, bismuth, uranium and transuranics abound;
some planets will have to be explored only by heavily armored robots;
the planets will be intensively mined for heavy elements rare elsewhere but abundant here;
the discoverers, drawing royalties on millions of the richest mines in the galaxy, will "'...command more resources than many civilizations...'" (p. 791).

Wealth beyond the dreams of Nicholas van Rijn: Satan and Mirkheim were each only one planet. An entire new phase of interstellar history, now spread across several spiral arms, is about to begin as the series ends.

"A Wilderness Of Stars"

Originally published on Poul Anderson Appreciation, 21 April 2012.

Even with faster than light spacecraft, science fiction (sf) characters rarely venture outside their home galaxy. While traveling within the galaxy, Poul Anderson's David Falkayn sees "...a wilderness of stars...", including the Milky Way, its satellite galaxies, the Magellanic Clouds, and its sister galaxy in Andromeda. (1) These names evoke a few other sf works. Both Isaac Asimov and Larry Niven present an entire species fleeing from the Milky Way to a Magellanic Cloud. Asimov's non-human beings, few in number, need only a hyperspace ship or two whereas Niven's beings, an entire population, travel at sub-light speeds in a Fleet of Worlds.

 

In James Blish's Okies tetralogy:

New York flies to the Greater Magellanic Cloud;
Mayor Amalfi of New York becomes Mayor of the Cloud;
the dirigible planet He flies from the Milky Way to and through the Andromeda galaxy, then to the Greater Magellanic;
Hevians, accompanied by Amalfi and other New Earthmen, fly He to the Metagalactic Centre where they briefly survive a cosmic collision;
the concluding one and a quarter volumes are, unusually, set entirely outside this galaxy.

Although Falkayn, while viewing the Magellanic and Andromeda galaxies, makes only a comparatively short interstellar journey, he addresses cosmic issues, like the aftermath of a supernova, that match those presented by Blish. Falkayn does not expect to travel much further:

"...the Magellanic Cloud and the Andromeda galaxy made small and strange by distances he would never see overleaped." (1)

Centuries after Falkayn, human beings have travelled around two or three spiral arms but remain within the galaxy. 

 

Elsewhere, Anderson does present:

faster than light intergalactic travel by human beings in The Avatar;
an intergalactic civilization in World Without Stars;
slower than light (STL) travel as far as the Magellanics and the Andromeda by self-programming artificial intelligences in Genesis; 
relativistically accelerating STL flight between clusters of clusters of galaxies and into the next universe in Tau Zero.

In World Without Stars, human beings no longer die of old age or disease and spaceships can make instantaneous jumps across intergalactic distances albeit with time-consuming spatial journeys between jumps. There is therefore both time and capacity for intergalactic exploration and for trade with the "Yonderfolk" of other galaxies although most of the action of the novel occurs on a planet orbiting a lone star located between galaxies. Anderson's attention to details and to scientific precision ensure that his works match the sometimes more spectacular-sounding events of Niven's Known Space or Blish's Okies.

(1) Poul Anderson, Mirkheim, London, 1978, p. 59.

The Last Planet

The last planet explored by Laure in the Cloud Universe:

unlike the others, it has an atmosphere - thin, mainly noble gases;

he wants to check element distribution on the surface;

the charged ionosphere prevents him from radioing the orbiting Jaccavrie;

nebular friction causes the planet to spiral towards its primary;

surface temperature is about 50 degrees Centigrade;

very little water;

large red dust storms;

a fiery ring of refracted light;

a jumbled plain;

chaotic terrain;

bare mountains;

gleaming black and brown rock;

deep purple sky;

hard ground;

1.22 Gs caused by planetary density;

strong wind;

high radiation;

heavy metals and radioactives -

- suddenly an exploding sky. Our old friend, the lethal unexpected.

As on Satan and Mirkheim, Poul Anderson creates drama in an uninhabited and uninhabitable environment.

A Few More Details About Hermes

(This may be the last post for December although I am not sure yet. We have just returned from a solstice ritual.)

Hermetian trees include stonebark and rainroof.
Ornithoids and buzzbugs fly between them.
One flying predator is called a steelwing.
Athena Falkayn wears "...a necklace of fallaron amber." (Rise Of The Terran Empire, p. 216)
The Falkayn manor house derives its name from the nearby Hornbeck brook.
Wyvernflies fly above the brook.
Terrestrial food and drink taste odd to Hermetians so no doubt the reverse would be true.

Sandra Tamarin flies near the Palomino River as it crosses an agrarian property of the Runeberg domain. She sees red-tiled houses of Follower families and the Runeberg mansion which, she knows, contains ancestral portraits and long tradition.

The Insignia Room, its walls decorated only by the colorful devices of the thousand Kindred, is on a high floor with  a view of sky and distant ocean. Grand Duchess Sandra sits at her desk before a three dimensional communication screen occupying half a wall and displaying the image of a hydrogen-breathing Baburite conqueror in his ship in synchronous orbit above Starfall.

The theme of Mirkheim is that times change. They can hardly change more than this.

Other Environments

Two other Technic History planets meriting discussion and documentation are Ivanhoe and Babur:

"The Three-Cornered Wheel" and "The Season of Forgiveness," both set on Ivanhoe, are collected in the first Technic Civilization Saga volume, The Van Rijn Method;

Mirkheim, with a passage set on Babur, is collected in the third volume, Rise Of The Terran Empire.

My next agendum is to reread these two stories and the relevant passage of the novel, then to summarize details of these planetary environments here on Poul Anderson's Cosmic Environments. Meanwhile, however, blog readers are of course welcome to preempt me with any information on either of these planets?

18 Oct 2014: See Ivanhoe and Babur.