Siri Goes to Alpha Centauri

Talk is growing concerning sending robotic missions to other planets, in this case the planets in the Alpha Centauri system.  That's right, a mission of many tiny, light-propelled spacecraft traveling at 20 percent the speed of light would leave our solar system to explore the great beyond.  Each little "probe" would cost about the same as an iPhone.  And this proposed voyage to our closest neighboring star system would take only 20 years.

The project is called "Breakthrough Starshot" and it involves space financier Yuri Milner (of the earlier "Breakthrough Listen"), cosmologist Stephen Hawking, and Facebook's Mark Zuckerberg. This is quite a cast of characters sure to encourage more interest and funding.

Here is what they are proposing:

...with current rocket propulsion technology, it would take tens or hundreds of millennia to reach our neighboring star system, Alpha Centauri. The stars, it seems, have set strict bounds on human destiny. Until now.

In the last decade and a half, rapid technological advances have opened up the possibility of light-powered space travel at a significant fraction of light speed. This involves a ground-based light beamer pushing ultra-light nanocrafts – miniature space probes attached to lightsails – to speeds of up to 100 million miles an hour. Such a system would allow a flyby mission to reach Alpha Centauri in just over 20 years from launch, and beam home images of possible planets, as well as other scientific data such as analysis of magnetic fields.

Breakthrough Starshot aims to demonstrate proof of concept for ultra-fast light-driven nanocrafts, and lay the foundations for a first launch to Alpha Centauri within the next generation. Along the way, the project could generate important supplementary benefits to astronomy, including solar system exploration and detection of Earth-crossing asteroids.

Of course, the challenges facing such a mission are enormous, and the initiative has a long list of topics that need to be resolved first, such as battery design, light sail strength, the risks of interstallar dusk, focusing light beams, communication over great distances, and more.  In other words, this mission will not take off tomorrow.  But the $100 million contribution from Mr. Milner will certainly help to get things started.

Trial runs in our own solar system are part of the planning stages.  For instance, we could send a small spacecraft to Pluto in about 3 days rather than 9 years.  So even without reaching distant planets, this project could transform how we study our own solar system.