20 evolution: the ages and tomorrow 



Thus, Hoyle and Lyttle set up their cosmos with an ex- 

 planation of the origin of whole galaxies, and they continue 

 with an outline of mechanics which gives some promise of 

 helping to understand the history of the stars and their 

 planets. In fact this ambitious theory takes into account 

 nearly all known cosmic phenomena. They believe that 

 planets are formed when one member of a binary system 

 blows up to produce a nova, a phenomenon which is known 

 to occur in our galaxy about every 250 years. They develop 

 ingenious mechanics for this planetary subtheory which 

 seems to explain quite well some of the unusual features of 

 our solar system, not the least of which is the concentration 

 of heavy elements in the planets and not in the sun. Our sun, 

 these cosmologists point out, is a stable, conservative hydro- 

 gen burner; that is, the energy generated is balanced by the 

 energy radiated. This will go on for some ten bilHon more 

 years before our sun will begin to flare up as a nova and 

 finally consume its inner planets including the earth. Hoyle 

 and his colleagues, Bondi and Gold, think that the expand- 

 ing universe concept is wrong because the galaxies are re- 

 ceding from each other much too fast. Their calculations, 

 based on the speed of the outer galaxies, would give a time 

 for the original explosion that would make the whole uni- 

 verse younger than some of its stars and our planet. Bondi 

 and Gold assume that the universe is actually in a "steady 

 state" and that the recession of the galaxies is due to the con- 

 stant addition of new matter, about one atom of hydrogen 

 to one gallon of space every 200,000,000 years. These as- 

 tronomers do not, at present, try to explain the constant 

 and regular appearance of hydrogen in the cosmos. They 

 do assume, however, that as space stretches to the limit the 

 outer galaxies, then apparently racing at the speed of light, 

 spill out of the system and disappear— a cosmos in which 

 equilibrium is maintained by the synthesis and annihilation 

 of matter in equal quantity. The organizing force that cre- 

 ates hydrogen is a main enigma of the cosmos. 



