Suborbital vehicles are spacecraft designed to travel into space but do not achieve the speed or altitude necessary to enter a stable orbit around the Earth. These vehicles typically reach altitudes above 100 kilometers, known as the Kármán line, where they experience a brief period of weightlessness before descending back to Earth. They are often used for research, tourism, and testing new technologies. Examples of suborbital vehicles include the Blue Origin New Shepard and the Virgin Galactic SpaceShipTwo. These vehicles provide opportunities for scientific experiments and commercial space tourism, allowing passengers to experience a few minutes of microgravity and view the curvature of the Earth.