Basically, two pivotal notions about the nature of the brain have been nullified. __22__ The second is that the brain steadily loses brain cells after age twenty or so and consequently relentlessly declines in mental capacities.  __23__ But scientists thought older brains lost the capacity to grow, and were fixed and static after puberty. It is now known that brain cells can sprout new dendrites and new synapses, forming new communication networks at any age. Thus, although everyone is born with a fixed number of brain cells, that innate figure does not define mental capacity. __24__ Brains with fewer cells can have just as much, or more, mental capacity than larger brains, depending on the lushness of neurons. The idea that a massive and progressive loss of neurons is an inevitable consequence of aging has also been thoroughly disproved. 

According to Russell L. Blaylock at University of Mississippi Medical Center, “The process by which the brain is ‘wired’ and even ‘rewired’ is referred to as plasticity. __25__ We now know that even the brains of adults are constantly changing and being rewired.”

    With spacecraft that can carry tourists into orbit and connect Paris to New York in less than two hours, the new heroes of space travel are not astronauts but daring captains of industry. This new breed of space pioneers are all using private money to push the final frontier as government space programs fall away. Times have changed. Once the space race was led by the likes of the U.S. space agency NASA that put the first man on the moon in 1969. 

    Today it is entrepreneur Elon Musk — the founder of Tesla electric cars and space exploration company Space—who wants to reach Mars in the 2020s. The furthest advanced — and most highly publicized — private space project is led by Richard Branson, the British founder of the Virgin Group. His shuttle, SpaceShipTwo, will be launched at high altitude from a weird-looking four-engined mother ship — which can carry two pilots and up to six passengers —before embarking on a three-hour suborbital flight. 

    Branson and his sons will be the first passengers aboard the shuttle when it is expected to launch late 2014. His company Virgin Galactic was given the green light in May by the U.S. Federal Aviation Agency (FAA) to carry passengers from a base in New Mexico, which is named “Spaceport America” — the stuff of science fiction. 

    The US$250,000 price of a ticket has not deterred more than 600 people, including celebrities such as actor Leonardo Di Caprio, from booking their seats.