from the surface of Mars. The big unanswered question is, What belched? Subsurface Martian cows are highly unlikely. But scientists are seriously considering the possibility of bacteria. " As The Independent picks up the story: " One possibility is that the methane is produced by Martian microbes living deep enough for underground water to be in liquid form. At this depth they could be living o...

[1] We argue that key features of thrust earthquake triggering, inhibition, and clustering can be explained by Coulomb stress changes, which we illustrate by a suite of representative models and by detailed examples. Whereas slip on surface-cutting thrust faults drops the stress in most of the adjacent crust, slip on blind thrust faults increases the stress on some nearby zones, particularly ab...

Close circumnavigation is an important function indispensable for servicing satellites. We discuss the bielliptic yaround maneuver by impulsive thrust control for a small and low cost servicing satellite ying around a target satellite. An optimal feedback control scheme for the thrust is proposed to maintain this trajectory in the presence of disturbances. The extended Kalman lter is employed t...

Objectives To analyze the kinematics of cervical rotation-traction manipulation (CRTM). Methods An experimental study measuring the kinematics of CRTM was conducted. A total of 18 healthy volunteers participated in the study. A single manipulator operated the CRTM for all subjects. Motion capture technology was adopted to track the trajectory during the CRTM operation. Results The manipulat...

The Main Central Thrust shear zone is the dominant crustal thickening feature in the Himalayas, largely responsible for the extreme relief and mass wasting of the range. Along the Bhagirathi River in NW India, the Main Central Thrust is several kilometers thick and separates high-grade gneisses of the Greater Himalayan Crystallines from Lesser Himalayan metasedimentary rocks. Th-Pb ion micropro...

The Himalayan mountain range has been the locus of some of the largest continental earthquakes, including the 2015 magnitude 7.8 Gorkha earthquake. Competing hypotheses suggest that Himalayan topography is sustained and plate convergence is accommodated either predominantly on the main plate boundary fault, or more broadly across multiple smaller thrust faults. Here we use geodetic measurements...

New flight test maneuvers and analysis techniques for evaluating the dynamic response of in-flight thrust models during throttle transients have been developed and validated. The approach is based on the aircraft and engine performance relationship between thrust and drag. Two flight test maneuvers, a throttle step and a throttle frequency sweep, were developed and used in the study. Graphical ...

successful development, evaluation, and qualification of propulsion systems such as turbojet and turbofan engines and rocket motors require the measurement of the performance and reliability of these systems. thrust stands or testers are instruments for solid and liquid motors test. in this paper, a method for calculating of solid motors random vibrations effects on a thrust stand structure is ...

High thrust-to-power ratio on Hall-effect thrusters allows for more efficient thrust generation and better overall performance. It allows Hall-effect thrusters to perform more thrust-intensive maneuvers such as orbit raising, thus saving the mass of a second engine purely for those maneuvers. This paper presents the initial performance measurements of aHall-effect thruster using in-channel elec...