Hubble Space Telescope secondary mirror vertex radius/conic constant test

The Hubble Space Telescope backup secondary mirror was tested to determine the vertex radius and conic constant. Three completely independent tests (to the same procedure) were performed. Similar measurements in the three tests were highly consistent. The values obtained for the vertex radius and conic constant were the nominal design values within the error bars associated with the tests. Visual examination of the interferometric data did not show any measurable zonal figure error in the secondary mirror

FEDERAL-STATE RELATIONSHIPS IN AGRICULTURE

Agricultural and Food Policy,

The Faustian Grip of Academic Publishing

The journal acquisition budget of libraries is not increasing at the same rate as subscription rates creating the serials' crisis. Many solutions have been proposed including the freely available electronic journal. However, all the solutions suffer the same Faustian Grip - namely that the actors in the academic publishing game have little or no incentive to stop publishing in the current journals. We examine those incentives concluding that even with a better more efficient technology, the actors will not change from the current academic publishing institution, and the serials' crisis will remain.serials crisis journal pricing academic publishing

GOALS OF DEMOCRACY

Public Economics,

Assessment of the present NASA optical metrology capabilities and recommendations for establishing an in-house NASA Optical Metrology Group

An investigation into when it was first recognized that there was a deficiency in NASA optical metrology oversight capability, why this deficiency existed unnoticed for so long, and a proposal for correcting the problem is presented. It is explained why this optical metrology oversight is so critical to program success and at the same time, why it is difficult to establish due to the nature of the technology. The solution proposed is the establishment of an Optics Metrology Group within the NASA/MSFC Optics Branch with a line of authority from NASA S & MA

Congratulatory Note on the Occasion of the Centennial Celebration of the Iowa State University College of Veterinary Medicine

A note from President W. Robert Parks congratulating the College of Veterinary Medicine on its centennial anniversary

Pulsed plasmoid electric propulsion

A method of electric propulsion is explored where plasmoids such as spheromaks and field reversed configurations (FRC) are formed and then allowed to expand down a diverging conducting shell. The plasmoids contain a toroidal electric current that provides both heating and a confining magnetic field. They are free to translate because there are no externally supplied magnetic fields that would restrict motion. Image currents in the diverging conducting shell keep the plasmoids from contacting the wall. Because these currents translate relative to the wall, losses due to magnetic flux diffusion into the wall are minimized. During the expansion of the plasma in the diverging cone, both the inductive and thermal plasma energy are converted to directed kinetic energy producing thrust. Specific impulses can be in the 4000 to 20000 sec range with thrusts from 0.1 to 1000 Newtons, depending on available power