A NEW space race is on, not between superpowers, but between three billionaire businessmen with their space-based enterprises. Their goal, each in their own way, is to pioneer space tourism and to move space travel away from an exclusive activity involving select, rigorously trained astronauts often with military backgrounds to one in which, theoretically, ordinary people can participate.

The first stage of this race has been won by 71 year-old flamboyant British civil aviation magnate Richard Branson of the Virgin Group of companies including Virgin Airways and his space venture, the rather grandiosely named Virgin Galactic. On July 11, 2021, the Virgin Galactic spaceplane VSS2 on its Unity 22 mission successfully completed the craft’s fourth crewed sub-orbital test flight up to the edge of space and back, carrying two pilots and four passengers including Branson, Virgin’s lead operations engineer and its (female) chief astronaut instructor, and India-born Virgin Galactic vice president of Government Affairs and Research Operations Sirisha Bandla looking after passenger experience. The passengers experienced four minutes of “weightlessness” floating around inside the craft, saw a near-black sky and marveled at the sight of a blue spherical Earth with its horizon curving away in the distance. These are the key features being promoted to potential passengers of future commercial space tourism flights.

Around 600 persons have already booked seats on future Virgin Galactic flights at an eye-popping $250,000 (Rs1.86 crores) each, putting into realistic perspective the claims of space tourism being opened up to the “common man”.

Towards further perspective, Branson and Unity 22 did not really reach space, but remained at sub-orbital altitudes. Nor was Branson the first civilian space tourist. That achievement belongs to American multi-millionaire businessman and former aerospace engineer Dennis Tito who paid a whopping US$ 20 million (Rs150 crore) to rocket up to the International Space Station in 2001 aboard a Russian Soyuz launcher and spent eight memorable days in the ISS. We shall discuss these aspects further below, but first a closer look at the Unity 22 mission itself.
  
VSS UNITY 22
MISSION
The Unity mission took off from the company’s Spaceport America, partly funded by the state government, near the town of Hot Springs, New Mexico, at 8:40 am local time.  The spaceplane VSS Unity, with wings that can fold both backward and horizontally from an upright position, was attached to the underside of the “mother ship,” a Virgin White Night 2 launcher plane named VMS Eve after Richard Branson’s late mother.

The aircraft climbed slowly over 45 minutes to an altitude of 50,000 feet (about 15 km) where the Unity craft was released and its rocket engine ignited.  Over the next 60 seconds, Unity then rocketed up to its maximum 53 miles or 86 km altitude above the earth’s surface at Mach 3 or three times the speed of sound. At this point, the engine cut out and spacecraft climbed to its peak altitude. During this period, the passengers experienced “weightlessness,” unbuckled themselves and started floating in the cabin. While this is popularly called weightlessness, sometimes confused with zero gravity which is definitely not the case, reality is that the earth’s gravity continues to have most of its influence at this altitude. The sudden deceleration of the spacecraft balancing the residual forward momentum and the micro-gravitational pull result in this momentary period where objects and people float in apparent “weightlessness”.

After about a minute, the pilots maneuvered the spacecraft with its belly down in preparation for descent. This maneuver also enabled the passengers to get a better view of the black sky above and the Earth below.

At this point, the craft’s wings are “feathered,” that is raised to a near-vertical position much like a badminton shuttlecock, and commences its descent. At an altitude of around 24 km, the wings are lowered to their normal near-horizontal position for the final glide and normal runway landing back at the Spaceport. The total journey took about 90 minutes.

SPACECRAFT AND PLANE 
Virgin Galactic’s launcher aircraft and spaceplane are about twice the size of their predecessor models, White Knight 1 and Virgin Space Ship1 or VSS1, originally designed and developed in the early 2000s by Scaled Composites, a company founded and run by the late Paul Allen, co-founder of Apple, and aircraft engineer Burt Rutan. Their prototype won the prestigious Ansari X Prize in 2004. Virgin first entered into a partnership with the company and jointly set up The Spaceship Company to manufacture the craft, ordered five sets, and eventually took over the company in 2012.

The rocket engine, originally designed and made by Nevada Space Corporation (NSC), a sub-contractor for Scaled Composites, has undergone many changes in design and fuel, and has at least been partially responsible for the long delay between Branson announcing his plans for space tourism in 2004 to the rehearsal flight on July 11. Today the redesigned engine is made wholly in-house by Virgin Galactic. Currently, the engine runs on polyamide plastic fuel with nitrous oxide as oxidiser.

The space ship is specially designed for sub-orbital flight, enabled by the slow speed of descent through the earth’s atmosphere compared to conventional spacecraft in orbit around the Earth that must re-enter the atmosphere at high speeds and withstand enormous heat and mechanical stresses thereafter, necessitating heat shields and other structural features. VSS2 is also capable of descent at almost any angle and uses its foldable wings and “feathering” maneuver to achieve efficient powered ascent, descent and glide. However, it was a premature “feathering” of the spaceplane before it reached peak altitude that resulted in a horrific crash of a VSS2 craft in 2015.

Virgin Galactic plans to develop an orbital version soon, and also foresees a hypersonic version that could potentially be used as a high speed passenger aircraft.

WHERE DOES
SPACE BEGIN?
Richard Branson had originally planned to fly on the first commercial flight along with the first paying passengers, but apparently flew on this earlier test flight in order to be one up on his rival, the Amazon boss Jeff Bezos, who had announced his first flight along with a very high-paying passenger on July 20, 2021. The one-upmanship has been denied by Branson, but has clearly sparked off some bad blood between the two billionaires. To keep up appearances, however, Bezos himself tweeted a “Godspeed” message to Branson before the Unity 22 mission on July 11, and also congratulated him after the craft landed safely.

On the other hand, the CEO of Bezos’ Blue Origin company, tweeted sarcastic comments comparing Virgin Galactic’s craft unfavourably with Blue Origin’s New Shepard spacecraft. Blue Origin’s craft was a real rocket not a plane, he remarked, had much bigger windows for better passenger viewing and, above all, its passengers “would not have an asterisk after their name” since they would have reached above 100 km altitude, accepted “by 96 per cent of the world” as being the demarcation line for space, not the 83 km peak of VSS2!

100 km or the Karman line is recognised by almost all international aeronautic and astronautic associations as the altitude demarcating space. This definition was arrived at by Hungarian-American scientist Theodor von Karman, revising it upward from his own earlier calculation of 86 km, as the altitude beyond which aerodynamic forces of lift and drag cease to operate and where, therefore, rocket thrusters are required for maneuvers.

However, US agencies such as NASA, the Federal Aviation Administration etc recognise 50 miles or 80 km as the demarcation and awards astronaut wings to anyone flying higher. This is based largely on the reckoning that 50 km is the lowest that an orbiting satellite can fly, albeit in a highly elliptical orbit. However, scientists have pointed out, based on data from many thousands of satellites, that satellites with orbits in the 50-80 km range soon crash. 
 
BILLIONAIRES’ RACE
Jeff Bezos’s Blue Origin will clearly travel above the Karman line. The New Shepard is a fully automated rocket, with the thrill of full thrust rocket-powered flight to space. It is designed to carry six paying passengers, maximising revenue by eliminating pilots and crew and, minus thrusters, its spacecraft will bring passengers back by parachute. An unknown passenger has paid US$ 28 million for the 11 minute ride on July 20 with Bezos, his brother and octogenarian woman aviator Wally Funk. Of course, only time will tell if passengers will shell out much higher amounts for a few thousand kilometres ride extra and the absence of an imaginary asterisk!

However, if altitude is to be the test, Elon Musk has Branson and Bezos beat by a long way. With the hugely powerful SpaceX ‘Heavy’ launchers, Musk plans to take passengers on a seven-day orbital trip on its Crew Dragon at a whopping US$ 25 million and is also planning trips to the International Space Station 400 km above the Earth. Being the super-ambitious person that Musk is, he is even thinking of trips to the Moon!