Notes on the Aliens knocked up for Scone ======================================== Solar System and Planet ----------------------- Star E Indi is 11.2 light years away in the Indus constellation (southern sky RA 22 Dec -57), a K5 star with surface temperature 4500K, its radiation peak is at 644 nm (red) , with luminosity 4.8e25 (12% Sun). Mstar = 1e30kg, 50% of Msun The planet Plando orbits 1.73E11 m (1.15 au) from the star, once every 1.75 years, The insolation received gives a radiative temperature of 260K (cf 280 for Earth). [Something feels wrong here] Other planets are Paline at 0.30 au orbiting every 0.23 Earth years (510 K), Plune is in a 3/2 resonance, at 0.34 years, 0.39 au, (446K) with an asteroid belt at 0.93 au (289K). Can't be bothered with gas giants The planet is metal rich, with much larger inner cores and thinner crust. The large amount of radionucleides encourages active plate tectonics and high CO2 recycling, hence a CO2 atmosphere (0.1% cf 0.033 Earth), keeping the overall temperature up to about 15'C at the equator, but with extensive ice caps. The active vulcanism has resulted in small platelets and many island chains. The oceans are much less extensive, and rarely very deep, as the thin crust tends to form spreading zones that fill ocean depths. Atmosphere, 2 bar N2, what about O2? Because of the large metallic core, Plando's gravity is 1.5 g The orbit is elliptical, causing temperature variations and strong storms in the islands. No moon [implies problems getting on land] The Aliens ---------- Life originated around the nutrients spewing from volcanic vents on the margins of island chains. No description of DNA equivalent (how about dextro rather than laevo or vv). Standard ocean life, with aggressive carivores that can leave the ocean for short times. Keen on multiples of 2. The aliens evolved from 8 legged hippo-like creatures. As they came on land, the first pair of legs atrophied to form 4 fingered hands, the third pair are used to cradle the infants. The aliens are hermaphrodite, with seasonal hormonal changes that make them male for the winter, female for the summer. Lungs are placed at the sides, with only weak muscles to control them, walking expands and contracts them to improve efficiency. WHAT ABOUT THE PROBLEMS WHEN STATIONARY. How about using the 3rd pair of limbs to massage the lungs. Because of this the creatures never sleep. [Getting less keen on this, as it ssems impractical] Brain internal, with local nerve centres near eyes (binocular pair at front at base of arms, one at top of each other leg. The mouth is placed between the 2 front legs, which have moved outwards to accommodate it. Due to high G, animals must be smaller, say 3 feet at the shoulder. The aliens evolved intelligence on the sea-shore (cf Aquatic Ape), with limited ecological pressure due to small islands, strong competition from the sea. Fast reactions needed on high g world, achieved by effecient brain and local signal processing at extremeties. Short life span - 30 earth years Young start with gills in warmed rock pools, developing in 5 Plando years from neuter to male at autumn change. I/R vision helps with night hunting. Communicate by hoots produced by controlling lung flaps (good in dense atmosphere). Visual communication by color changes in flaps of skin with variable blood supplt. Hence written language extensively colour-coded. Smell very poor, but good taste organs on fore-limbs. The Culture ----------- The main events of the year are the Changes, when all the creatures change sex. On the male-female change, the transfer of 'sperm' occurs, triggering hormonal changes. JUSTIFY HOW THIS COULD HAVE EVOLVED - STORMS? Learnt English from "I Love Lucy" and the OU. Very strong communal feeling. Concept of the individual, but not the leader, all decisions made by committee/PR. Art heavily influenced by this, with all artform participative, little concept of A playwright or composer. Rabid vegetarians, living on sea-food (seaweed etc). Very strong associations between meat-eaters, their predators and so evil. Early understanding of fire due to volcanoes. Civilisation based on geothermal power, religion worshipping the volcano (Land on Hawaii, astronomers as priests?) Very strong emphasis on building on what has gone before, gradual progress, evolution rather than revolution. Duplicity very rare, decisions made slowly. Limited concept of war. Seamless integration of computers into life, with VR dominant in democracy and leisure. Concencus, consistency and compatibility are watchwords. Technology advanced rapidly due to extensive geothermal power and easy access to metals. Currently involved in mining rest of solar system Purpose of visit to Earth is scientific curiosity. 1935 Radio traffic out 1947 Expedition planned 1957 Expededtion leaves, using antimatter technology to launch a very advanced computer that can pretend to be the aliens themselves The Message ----------- Broadcast on 4.4623 GHz (pi * 21cm), picked up at Parkes in Australia by John Bellingham at Ames, as part of NASA's SETI Microwave Observing Project, using the targetted search (nearest 800 stars, 1 Hz discrmination) Later a new signal is spotted at 4.0566 GHz (ie blue shifted by 0.1c), increasing by 0.0096 Ghz per day (ie arrival in 4 weeks, deceleration at 1.5 g. Work out distance! Technology strong in metals, computers, spaceglight, particle physics, weak in medecine and cosmology