Suborbitals

Suborbitals refers to objects or spacecraft that travel into space but do not complete an orbit around a celestial body. To achieve orbit, an object must attain a specific horizontal velocity to counteract the gravitational pull. Suborbital flights reach altitudes above the Kármán line, the internationally recognized boundary of space at 100 kilometers (62 miles), but their trajectory is such that they fall back to the surface before completing a full revolution.

These flights are characterized by a parabolic trajectory. After ascending into space, the object travels along this arc, reaches its apogee (highest point), and then descends back to Earth. The duration of suborbital flights is typically short, often measured in minutes, with a significant portion of that time spent in the vacuum of space.

Suborbital technology has various applications. It is used for scientific research, allowing instruments to gather data in the near-space environment without the complexity and cost of orbital missions. It also forms the basis for space tourism, enabling passengers to experience weightlessness and view the curvature of the Earth from a vantage point typically between 80 to 110 kilometers above the surface. Companies are developing and operating suborbital vehicles for both research and commercial passenger flights. Early pioneers like X-15 conducted suborbital flights in the mid-20th century, and modern efforts continue to advance this capability.