How Will We Get to Alpha Centauri?

About 4. 3 light-years from Earth lies our
closest stellar neighborhood. The Alpha Centauri system consists of three
known stars. Alpha Centauri A and Alpha Centauri B are
a binary pair, which meansthey orbit a common center of mass. The third star, Proxima Centauri, is the closest
to Earth at about 4. 22 light-years away. In 2016, astronomers detected an Earth-sized
planet orbiting Proxima Centauri within thestar’s habitable zone – the right distance
to potentially support liquid water on its surface. Which is why eyes are on Alpha Centauri as
our first destination once we master interstellar travel. So is this deep space journey possible in our lifetime?And if so, how will we get there?Outer space is bigger than we can comprehendand sending a spacecraft into its depths takes a lot of time. NASA’s Voyager 1 is Earth’s farthest spacecraft
to date. It was launched in 1977, and in 2012, it was
the first craft to enter interstellar space. If Voyager 1 was pointed in the direction
of Alpha Centauri, it would still take tensof thousands of years to reach the system. And that’s because its propulsion system is
not ideal for deep space travel. So clearly we need a faster way to get to our stellar neighbors. Some scientists believe that our best attempt
at interstellar travel are lightsails. These sails would be made of ultra-thin sheets
that will be propelledusing light instead of wind. One of the major initiatives researching their
potential is Breakthrough Starshot. The program, initially backed by late cosmologist
Stephen Hawking, aims to create a nanocraftcomprised of a lightsail and a gram-scale
wafer that hosts a number of instrumentscalled a StarChip. The nanocraft has a mirror-like sail design
and is measured at 10 square meters with amass of less than 1 gram. By comparison a penny weighs 2. 5 grams,so these spacecraft will be ultralight. The lightsail will purportedly be accelerated
by laser radiation pressure from Earth atabout 20 percent the speed of light. The planned laser array, called a Light Beamer,
will fire beams as powerful as 100 gigawattsof specific wavelengths of near-infrared light. The nanocraft sail would need to reflect a
huge majority of the laser light to avoidinstantly burning up on contact. The idea is to launch thousands of nanocraft
at once to increase the chances that at leasta few will conquer the elements and reach
Alpha Centauri. If they do make it, it’s estimated, the
journey will only take around 20 years. Though some critics are skeptical about the
ability to execute Breakthrough Starshot,some of the world’s greatest minds are actively
working to make it a reality. The project is pushing the boundaries of science,
challenging humans to create an entirely newmaterial that meets all the extreme needs
of the lightsailsand to design the largest laser ever constructed. But, if engineers and scientists are able
perfect these pint-sized spacecraft and weachieve interstellar travel, humanity will
be rewarded with an entirely new understandingof the alien worlds beyond our own. If you’re looking to learn more about space exploration and astronomical phenomenabe sure to watch this episode of Space Crafts. And don’t forget to subscribe to Seeker for all things science. Thanks for watching!