Virgin Galactic’s VSS Unity (Virgin Space Ship Unity) made its second flight into space, reaching an altitude of 55.87 miles (89.9 kilometers) on February 22, 2019. The American space company released amazing footage of the flight.
The first “spaceflight” of VSS Unity was on 13 December 2018. The suborbital spacecraft Notes 1 reached an altitude of 82.7 km (51.4 miles), officially entering outer space by US standards. Notes 2
On February 22, 2019, during the second spaceflight, the supersonic, rocket-powered VSS Unity has reached an altitude of 295,007 feet (89,918 meters) and a top speed of Mach 3.04 (2,255 mph, 3,629 km/h).
It three crew for the first time: two test pilots (Dave Mackay, the company’s chief pilot, and Michael “Sooch” Masucci) and a mission specialist (Beth Moses, Virgin Galactic’s chief astronaut instructor).
The crew enjoyed extraordinary views of Earth from space and, during several minutes of microgravity. Moses floated free to complete a number of cabin evaluation test points.
VSS Unity lifted by a plane named “WhiteKnightTwo” until the altitude high enough to fire its hybrid rocket motor.
1. Suborbital spaceflight
When a spacecraft reaches outer space, but its trajectory intersects the atmosphere or surface of the gravitating body from which it was launched so that it will not complete one orbital revolution, this is called a “suborbital spaceflight”.
2. Where the outer space begins?
There is no clear boundary between Earth’s atmosphere and space, as the density of the atmosphere gradually decreases as the altitude increases. There are several standard boundary designations, namely:
- The Fédération Aéronautique Internationale (FAI, the world governing body for air sports) has established the Kármán line at an altitude of 100 km (62 mi) as a working definition for the boundary between aeronautics and astronautics. The line is named after Theodore von Kármán (1881-1963), a Hungarian American engineer and physicist, who was active primarily in aeronautics and astronautics. He was the first person to calculate at which altitude the atmosphere becomes too thin to support aeronautical flight. At an altitude of about 100 km (62 mi), as Theodore von Kármán calculated, a vehicle would have to travel faster than orbital velocity to derive sufficient aerodynamic lift from the atmosphere to support itself.
- The United States designates people who travel above an altitude of 50 miles (80 km) as astronauts. Based on this standard, the USS Unity has reached the outer space.
- NASA’s Space Shuttle used 400,000 feet (76 mi, 122 km) as its re-entry altitude (termed the Entry Interface), which roughly marks the boundary where atmospheric drag becomes noticeable, thus beginning the process of switching from steering with thrusters to maneuvering with aerodynamic control surfaces.
In 2009, scientists reported detailed measurements with a Supra-Thermal Ion Imager (an instrument that measures the direction and speed of ions), which allowed them to establish a boundary at 118 km (73 mi) above Earth. The boundary represents the midpoint of a gradual transition over tens of kilometers from the relatively gentle winds of the Earth’s atmosphere to the more violent flows of charged particles in space, which can reach speeds well over 268 m/s (600 mph).
- “Virgin Galactic Reaches Space Again, Flies Test Passenger for 1st Time” on Space.com
- “Virgin Galactic makes record-breaking second space flight with 3 crew aboard” on New Atlas
- “Virgin Galactic spacecraft sets a new speed, altitude record” on India Times
- VSS Unity on Wikipedia
- Suborbital spaceflight on Wikipedia
- Outer space on Wikipedia