An observation about the relative hardiness of bacterial spores and planetary quarantine
An observation of ionospheric convection and auroral arc motion
An observation of plasma inside of microwave boosted thruster
An observation of polar aurora and airglow from the ISIS-II spacecraft
An Observation of the Soft X-ray Diffuse Background with High Energy Resolution Micro-calorimeters
An Observational Demonstration of Angle Error in Visual Magnitude Estimates
An Observational Error Model, and Application to Asteroid Mass Determination
An Observational Investigation of the Comet-Asteroid Connection
An Observational Perspective on Some Aspects of Early Stellar Nucleosynthesis
An observational search for large-scale organization of five-minute oscillations on the sun
An observational study of astronomical magnetic fields and their role in star formation
An Observational Study of Diurnal Variations of Marine Stratiform Cloud.
An observational study of quiescent novae
An observational study of the variability of ocean wind stress and sea surface roughness
An observational test for the ionospheric or magnetospheric origin of night-time geomagnetic positive bays at low and mid latitudes
An occultation by Charon
An oceanic flood basalt province within the Caribbean plate
An oceanic flood basalt province within the Caribbean plate
An Odd Couple: Designing A Common ACMS for Two Very Different Spacecraft
An odyssey for the turn of the millennia