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Faber-Jackson (spheroidals) & Tully-Fisher (disks)

if


then (dividing by R²)


relating the surface brightness (I) to the square of the surface density (). i understand that relation to be the crucial core of the FJ/TF relations, linking light-generation & star-formation (I) to physical characteristics of galaxies (M,R). The fact that star-formation increases with the square of the disk density underlies the TF relation for disk-galaxies. Something similar occurs for spheroidals.

Note too


the contours of constant surface-brightness and mass-to-light ratio have the form M ~ R²; the contours of constant total luminosity have the form M ~ R. These lines can be plotted on the (M,R) plane; and the positions of various galaxy types can be over-plotted, adapting from the figure from Galaxy Formation & Evolution:


Given the correlation between Irregulars evolving into Spirals (Ir --> S), perhaps the presence of large, luminous (high L), but dim (low I), spiral-type LSB galaxies, e.g. Malin 1, implies the presence of a corresponding class of irregular-type LSBs ? Because LSB are "crouching giants", lurking below the ambient background sky surface-brightness, pattern recognition techniques may only extract "nice neat spirals" from the noise. But, even as conventional Irregulars disk down into Spirals, perhaps there exist large but dim LSB Irregulars slowly disking down into LSB Spirals like Malin 1 ??

what about Mag-Lev for freight trains ? Perhaps electro-magnetic forces could "carry" larger loads, more energy efficiently, e.g. "you could recoup your energy costs, whilst the train decelerates" ? Mag-Lev technology resembles "rail-guns" & "mass-drivers"; ergo development of super-heavy-payload Mag-Lev freight-trains could help develop "mass-drivers", to accelerate super-heavy-payloads, e.g. space-factories, to orbital velocities, for economic exploitation, of space:


theoretically, earth-orbiting "EM wiffle-ball-scoops" could "catch" and decelerate moon-launched payloads. Hypothetical earth-launched Mag-Lev "cargo vehicles" would resemble space-shuttles, which would release payloads in orbit, before gliding back down to earth:

CharonY, on 5 April 2012 - 11:43 PM, said:

are you denying, that NRPs, are assembled, by NRP-Ss, which are themselves gene-encoded Proteins, assembled on Ribosomes ?

CharonY, on 4 April 2012 - 11:33 PM, said:

Today, after four billion years of losing competition to Ribosomes, extra-Ribosomal Proteins (NRPs) are limited to the "molecular margins" of bio-chemistry, i.e. "secondary metabolites". But, the "relic remnants" of the NRP system, seen today, are (plausibly) a "dim echo" of the original system -- many of whose functions were replaced, by Ribosomally-generated Proteins, over the aeons. I.e. some Ribosomal Proteins, today, (plausibly) perform the functions that, 4Gya, NRPs performed (less well).

Quote

The "earlier form of peptide synthesis [which] must have existed" was referenced, in passing, as the "Non-Ribosomal Protein" (NRP) system. Wikipedia has an entry on the topic, which I cited.

Ipso facto, the article implies:

• an archaic NRP system existed >4Gya
  
• NRPs are assembled from NRP-S, which today are standard gene-encoded, Ribosomally-assembled, Proteins
  
• i.e., today, w.h.t.: DNA ---> Ribosomes ---> NRP-S ---> NRP
  
• ergo, archaically, w.h.t.: proto-ribosomes ---> NRP-S ---> NRP

Prima facie, implied proto-Ribosomes were "proto-Genes", composed of fragile RNA, augmented by Protein scaffolding for molecular structural support; numerous such (RNA+P) existed (originally individually, later conglomerating into multi-gene complexes), coding for numerous NRP-S/NRP molecules; with the evolution, of DNA, Genes were "backed up" onto superior DNA, and the (RNA+P) complexes remained, only to translate between DNA vs. Proteins; many NRP-S/NRP pathways were superceded, over the aeons,


until today only a few "molecular fossils" remain.

could you recover the source you mentioned, or anything on NRPs (the Wikipedia article discusses only a single class of NRPs).

CaptainPanic, on 5 April 2012 - 08:26 AM, said:

many asteroids are "carbonaceous", i.e. rich in carbon. Ergo, "carbonaceous" materials already exist, in situ, at least in the main asteroid belt. And, would not silicon work well, too (to form SiO2)? Silicon is perhaps the most common element in asteroids.

perhaps "nuclear broilers" are buildable, using "hot-running fission cores" as "light-bulb-elements", backed by a reflective shield, like a "nuclear-bulb flash-light":


heat radiation, from the fission cores, would be radiated onto, and reflected back onto, space-ores in the "hopper" or "crucible" below (per artificial gravity).