the outer shell of a seed is called husk.
the outer shell of a seed is called husk.
what is the outer shell of a seed called?
husk
husk









































husk (or hull) in botany is the outer shell or coating of a seed. it often refers to the leafy outer covering of an ear of maize (corn) as it grows on the plant. literally, a husk or hull includes the protective outer covering of a seed, fruit, or vegetable. it can also refer to the exuvia of bugs or small animals left behind after moulting.









































in cooking, hull can also refer to other waste parts of fruits and vegetables, notably the cap or sepal of a strawberry.
husk
zero-drag satellites or equivalently "drag-free satellites" are satellites where the payload follows a geodesic path through space only affected by gravity and not by non-gravitational forces such as drag of the residual atmosphere, light pressure and solar wind. a zero-drag satellite has two parts, an outer shell and an inner mass called the "proof mass". the proof mass floats freely inside the outer shell, while the distance between the outer shell and the proof mass is constantly measured. when a change in the distance between the outer shell and the proof mass is detected, it means that the outer shell has been influenced by non-gravitational forces and moved relative to the proof mass. thrusters on the outer shell will then reposition the outer shell relative to the proof mass so that its distance is the same as before the external influence changed it. the outer shell thus protects the proof mass from nearly all interactions with the outside that can cause acceleration, except those mediated by gravity, and by following the proof mass, the outer shell (which is to say, the rest of the spacecraft, carrying instruments, etc.) itself follows a geodesic path.
zero-drag satellite