Monday, June 27, 2016 by spacenews
Stephen Hawking and Yuri Milner’s Breakthrough Starshot initiative wants to send an army of small probes out to Alpha Centauri — at one-fifth the speed of light, no less — to look for aliens and exoplanet habitability.
(Article by Neel V. Patel)
There are at least five big questions as to how they’ll actually get this project off the ground and into space, but one area in which the project seems to be progressing is the design of the little buggers that are supposed to find aliens for us.
For those who are unfamiliar, Milner and Hawking’s plan calls for building inexpensive spacecraft comprised of an obscenely large and ultra-thin solar sail attached to a gram-sized piece of electronic equipment that looks like it came from the inside of a computer. A system like that wouldn’t be capable of doing much more than gathering basic images, but if you’re trying to make something at the cost of a smartphone that you can send out into interstellar space, that’s a pretty notable feat anyways.
And it turns out we should be testing these things out very soon. Cornell University researchers are set to launch 100 prototype “chipsats” to the International Space Station on July 6, where they will be deployed and tested for their ability to collect and transmit data and stay functional. After a few days of this, the miniature satellites will be allowed to drift off and burn up in the atmosphere.
It’s part of the Kicksat-2, the second iteration of a crowdfunding campaign to build cheap spacecraft that could be sent in large quantities to different worlds and make observations. Borne out of a doctoral research project, these chipsats are now the basis for what the Starshot initiative wants to send off to Alpha Centauri. The new test aims to prove that the chipsat platform is a cost-effective-yet-viable way to study other environments in space.
In fact, at Breakthrough Starshot’s introductory announcement, Milner held up a chip-sized computer that was actually based on designs created by the Kicksat engineering team.
These chipsats — called Sprites — will never actually replace what a state-of-the-art telescope can do in observing other planets and stars across the electromagnetic spectrum. But the square-shaped Sprites — about as wide as a few postage stamps — have some big advantages to them that bigger probes lack. You can send a ton of them out without having to worry if a few (or even most) are damaged during the journey. They’re small and lightweight, so they can travel much faster (which is how Milner and Hawking aim to get to Alpha Centauri in just about two decades’ time).
The launch of Kicksat-1, which was geared to test out the first generation of Sprites, was a failure. The container holding all the wee lil things failed to deploy, and instead just fell back into the atmosphere and burned up. Hopefully the Cornell crew has better success with the crowdfunded Kicksat-2 mission.
The main objectives include testing out the Sprites’ communication protocols and navigation systems. As is the theme of this project, inexpensive systems are key. So the communication system the Cornell team has built into the devices uses the same method that cellphone towers use to correspond with multiple mobile phones over the same radio bandwidth.
Meanwhile, the navigation system is comprised of a simple wire capable of generating a small magnetic field that basically turns the chipsat into an interstellar compass, with Earth’s magnetic field as ‘north.’
Developing both of these systems for long-distance travel is key, and the Sprites are nowhere close to having the capability of communicating with us or navigating on their own during a 4.3 light-year journey to Alpha Centauri. Also important will be developing an energy system that keeps the chipsats charged and running by the time they get to their destination.
Let’s hope the July test goes well. Then the only major obstacle holding back Starshot is figuring out how to fire off a 100-gigawatt light beam that launches the spacecraft without instantly vaporizing them. The Kicksat team is letting others figure that one out.