Co- and counter-helicity interaction between two adjacent laboratory prominences

The interaction between two side-by-side solar prominence-like plasmas has been studied using a four-electrode magnetized plasma source that can impose a wide variety of surface boundary conditions. When the source is arranged to create two prominences with the same helicity (co-helicity), it is observed that helicity transfer from one prominence to the other causes the receiving prominence to erupt sooner and faster than the transmitting prominence. When the source is arranged to create two prominences with opposite helicity (counter-helicity), it is observed that upon merging, prominences wrap around each other to form closely spaced, writhing turns of plasma. This is followed by appearance of a distinct bright region in the middle and order of magnitude higher emission of soft x rays. The four-electrode device has also been used to change the angle of the neutral line and so form more pronounced S-shapes

Comparisons of cross-section predictions for relativistic iron and argon beams with semiempirical fragmentation models

Cross-section predictions with semi-empirical nuclear fragmentation models from the Langley Research Center and the Naval Research Laboratory are compared with experimental data for the breakup of relativistic iron and argon projectile nuclei in various targets. Both these models are commonly used to provide fragmentation cross-section inputs into galactic cosmic ray transport codes for shielding and exposure analyses. Overall, the Langley model appears to yield better agreement with the experimental data

Space Exploration: Where We Have Been, Where We Are and Where We Are Going: A Human Perspective

NASA is moving forward towards the agency's new vision for space exploration in the 21st Century encompassing a broad range of human and robotic missions including missions to Moon, Mars and beyond. Exposure from the hazards of severe space radiation in deep space long duration missions is the show stopper. Langley has developed state-of-the-art radiation protection and shielding technology for space missions. The payload penalty demands a very stringent requirement on the design of the spacecrafts for human deep space missions. The exploration beyond low Earth orbit (LEO) to enable routine access to more interesting regions of space will require protection from the hazards of the accumulated exposures of space radiation, Galactic Cosmic Rays (GCR) and Solar Particle Events (SPE), and minimizing the production of secondary radiation is a great advantage. The better understanding of radiation environment (GCR & SPE) and their interaction is a key to the success of the program due to the vital role and importance of cosmic rays for space missions