The Nacreous Oughts

15 October 2018

ground control to major trump 

(via jim pike at memories of dallas on fb)

If there really was a book that contained the secret of life, it would not, assuredly, be called The Secret.

09 October 2018

the legend of woolly syrup 



01 October 2018


(theseastorm via)

Writers who use an extensive vocabulary (Ryling, A Theroux, Pynchon) are like microtonal composers; they just need more notes.

Rumi & "The Guests."

The Vulcan discovery paper finds an 8.47 earth-mass planet in a 42.378 day orbit around the star HD 26965 (omicron-2 Eridani A, HIP 19849, "Keid," HR 1325 & Gliese 166A), which is a triple with a white dwarf-red dwarf pair at 82" (some 418 AU), making one revolution in some 8000 years. The age of the system is given as 6.9 billion years--though the white dwarf may only be 122 million years old & must have been some kind of red giant before that (& then a "planetary nebula"--thought to be toxic for any nearby planetary life). Hipparchos gives the parallax as 0".1985657 & the visual magnitude of the K0 V primary as 4.43. It is metal-poor (Fe/H -0.42).

Some more general reflections...

Using a Bolometric Correction of -0.21 & a stellar temperature (given) of 5072 K, I get a visual luminosity of 0.373414809 & a bolometric luminosity of 0.453097366. (The radius works out to be 0.880224122--given as 0.87--so perhaps the BC should be a tad less.) With a stellar mass of 0.78 & a revolution period of 0.116022619, I find the semimajor axis of the planet to be 0.218974383. This gives a blackbody temperature of 490.3502805 (compare Venus at 328 & Mercury at 449): this is not by any means a habitable world! (Too bad nobody figured this in the dozens of news reports about "Spock's home planet"...)

If the planetary mass is 8.47 (given), its radius should be around 1.76; then I derive a density of 1.55, gravity of 2.73, & escape velocity of 2.19 times the Earth's (safely under the 3.19 that would hold molecular hydrogen at this temperature, thus producing a gas giant instead of a rocky world at start). The real question is how much of its original atmosphere will be left after its violent history with the evolution of 40 Eridani B (now 0.573 times the mass of the sun, but formerly at least an F-type star with some twice this). If I just plug in a low albedo like Mars's (0.15), I get a greybody temperature of 198 C. Greenhouse effect would presumably increase this. At surface temperatures such as this (I am ignoring for the moment the problem of a trapped--rotation climate), the atmospheric pressure must be at least 16 atmospheres for water not to boil. Would there still be this much left in the end? Could even a highly advanced civilization survive 10,000 years of living underground?


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