suborbital

Suborbital refers to a spaceflight trajectory that reaches outer space but does not complete an orbital revolution around Earth. In a suborbital mission, the vehicle does not achieve the velocity required to stay in orbit; after ascending to a maximum altitude, it follows a ballistic or gliding path back to Earth, experiencing a temporary period of weightlessness during the flight.

Suborbital profiles come in two main forms. Ballistic suborbital flights follow a curved, ballistic arc with minimal lift, while glide or spaceplane suborbital flights involve some lift-assisted flight during ascent and reentry, often ending with a runway landing. Altitudes commonly cited for suborbital missions are around the edge of space, roughly 100 kilometers (62 miles) and above, though exact definitions of space boundaries vary by organization. The flight duration is typically short, often around ten minutes from launch to landing, with a few minutes of microgravity.

Uses of suborbital flights include scientific research, technology testing, and commercial tourism. Researchers use short-duration microgravity and upper-atmosphere environments to conduct experiments in fields such as fluid physics, materials science, and life sciences. For reliable operations, suborbital missions are regulated by national agencies, which issue licenses and oversee safety and launch activities.

Notable examples of suborbital programs include Virgin Galactic’s SpaceShipTwo and Blue Origin’s New Shepard, both designed to reach space-like altitudes and then return for a controlled landing, enabling experiments and passenger flights without achieving orbital velocity.