TW meaning in Space Science ?

A tailwind is a wind that blows in the direction of travel of an object, while a headwind blows against the direction of travel. A tailwind increases the object's speed and reduces the time required to reach its destination, while a headwind has the opposite effect.

In aeronautics, a headwind is favorable in takeoffs and landings because an airfoil moving into a headwind is capable of generating greater lift than the same airfoil moving through tranquil air, or with a tailwind, at equal ground speed. As a result, aviators and air traffic controllers commonly choose to take off or land in the direction of a runway that will provide a headwind. However while on take-off and landing, headwinds are good because they allow you to use a shorter runway, in flight, headwinds are bad because they slow you down and require that you use more fuel to get to your destination. Conversely, tailwinds are bad on take-off and landing, but are good in flight.

In sailing, a headwind may make forward movement difficult, and necessitate tacking into the wind.

These two terms are accordingly used in business/finance.

Tailwinds and headwinds are commonly measured in relation to the speed of vehicles — commonly air and watercraft — as well as in running events — particularly sprints.