Beyond Apollo looks at Werner von Brauns pitch in 1969 to the Nixon administration to create a nuclear space program around the Nerva nuclear thermal rocket for shuttles and Mars rockets.
Von Braun concluded his presentation by discussing how the Mars program would provide a culmination for NASA’s Integrated Program Plan. Additional Mars expeditions would occur in 1983-1984, 1986-1987, and 1988-1989. NASA would establish a 50-person Mars Base in 1989, in time for the 20th anniversary of his presentation. By that time, NASA’s annual dollar outlay would stand at $5 billion and its share of Gross National Product would have declined to 0.3%, assuming a steady 4% per year growth in the national economy.
Centauri Dreams looks at the recent discovery of Brown Dwarf stars. Massive Astrophysical Compact Halo Object, (MACHO) a term for large astronomical bodies that can explain what seems to be dark matter in galactic haloes).
The final paper of the MACHO collaboration, published in 2000, concluded that a Galactic halo consisting entirely of MACHOs was now ruled out, and estimated that about 20% of the Galactic halo was in the form of MACHOs. The EROS team preferred to present its results as an upper limit on the number of MACHOs in the halo, with no more than about 8% of the halo in MACHOs having masses of about one-tenth to one times the mass of the Sun. A combined analysis of the two experiments showed that, within the uncertainties of each experiment, they are consistent with each other and that less than 20% of the halo is in the form of MACHOs.