Once upon a time, humankind had ambitions that led to such incredible projects as the first manned flight into space or the mission to the moon. The next step will be the colonization of the planets, and then the interstellar journey. The initiative of Breakthrough Starshot becomes the successor of human ambitions and promises to pave the way for the nearest stars.
Breakthrough Starshot, the brainchild of Russian businessman billionaire Yuri Milner, became known in April 2016 at a press conference in which famous physicists, including Stephen Hawking and Freeman Dyson, took part. And although the project can not be called full-fledged yet, the preliminary plan involves sending thousands of chips the size of a postage stamp on large silver sails that first enter the earth’s orbit and then be accelerated by ground-based lasers.
In two minutes of laser acceleration, the spacecraft will accelerate to one-fifth of the speed of light – a thousand times faster than any artificial device in the history of mankind.
Each device will fly for 20 years and collect scientific data on interstellar space. Having reached the planets in the star system of Alpha Centauri, the integrated digital camera will photograph in high resolution and send pictures to Earth, allowing us to look at our nearest planetary neighbors. In addition to scientific knowledge, we can find out whether these planets are suitable for human colonization.
The team that deals with Breakthrough Starshot is as impressive as the technology. The board of directors includes Milner, Hawking and Mark Zuckerberg, creator of Facebook. The role of the executive director is taken by Pete Warden, former director of the Ames research center at NASA. Several well-known scientists, including Nobel laureates, advise the project, and Milner put $ 100 million of his own funds to start the work. Together with colleagues, they invest more than $ 10 billion over several years to complete the work.
Although the whole idea seems to be absolutely sci-fi, there are no scientific obstacles to its implementation. This, however, does not necessarily have to happen tomorrow: in order for Starshot to be successful, a number of advances in technology are needed. Organizers and academic advisers believe in exponential progress and the fact that Starshot has been realized for 20 years.
Next you will find a list of eleven Starshot technologies and what hopes for their exponential development for the next twenty years are assigned by scientists.
Detection of exoplanets
Exoplanet is a planet beyond our solar system. Although the first scientific discovery of the exoplanet took place only in 1988, as of May 1, 2017, 3608 exoplanets were discovered in 2702 planetary systems. Although some of them resemble planets in the solar system, among them there are many unusual, for example, with rings 200 times wider than the rings of Saturn.
What is the reason for such a flood of discoveries? Significant improvement of telescopes.
Just 100 years ago, the largest telescope in the world was the Hooker telescope with a 2.54-meter mirror. Today, the Very Large Telescope of the European Southern Observatory consists of four large telescopes with a diameter of 8.2 meters and is the most productive ground-based astronomical facility that issues one scientific article per expert review per day.
Scientists use OBT and a special tool to search for solid extrasolar planets in the potentially inhabited zone of the star. In May 2016, scientists using the TRAPPIST telescope in Chile found not one but seven exoplanets of terrestrial dimensions in a potentially habitable zone.
Meanwhile in space NASA Kepler, specially designed for this task, has already identified more than 2000 exoplanets. The James Webb Space Telescope, which will be launched in October 2018, will provide an unprecedented view of whether exoplanets can support life. “If these planets have an atmosphere, JWST will be the key to uncovering their secrets,” says Doug Hudgins, an exoplanet scientist at NASA headquarters in Washington.
The mother ship Starshot will be launched aboard the missile and will release a thousand ships. The cost of transporting payloads using disposable rockets is enormous, but private service providers such as SpaceX and Blue Origin have demonstrated success in launching reusable rockets that are expected to significantly reduce launch costs. SpaceX has already reduced spending to $ 60 million for the launch of Falcon 9, and as the private space industry expands and reusable rockets become more common, the price will fall and fall.
Each 15mm Starchip (“star chip”) should contain a large array of ingenious electronic devices, such as navigation system, camera, communication laser, radioisotope battery, camera multiplexer and its interface. Engineers hope that they can squeeze all this into a small machine the size of a postage stamp.
In the end, the first computer chips in the 1960s contained a handful of transistors. Thanks to Moore’s law, today we can fit billions of transistors on each chip. The first digital camera weighed several kilograms and made 0.01-megapixel images. Today, the sensor of the digital camera makes high-quality color images of 12 megapixels and fits in the smartphone – along with other sensors like GPS, accelerometer and gyroscope. And we see how these improvements seep into the exploration of space with the advent of small satellites that provide us with qualitative data.
For Starshot’s success, we need to have a chip mass of about 0.22 grams by 2030. But if the improvements continue to come at the same pace, the forecasts suggest that this is quite possible.
The sail should be made of a material that will have a high reflectivity (in order to gain the maximum pulse from the laser), minimally absorbing (not to burn out of heat) and at the same time very light (it allowed to accelerate quickly). Three of these criteria are extremely important, and at the moment there is simply no suitable material for them.
Necessary achievements can come from automating artificial intelligence and speeding up the discovery of new materials. Such automation has come to the point that machine learning methods today can “generate libraries of candidates for suitable materials in tens of thousands of positions” and allow engineers to determine which ones are worth fighting for and which ones should be tested under certain conditions.
Although Starchip will use a tiny radioisotope battery during its 24-year journey, we still need conventional chemical batteries for lasers. Lasers will need to release enormous energy in a short time, which means that the energy will have to be stored in batteries nearby.
Batteries improve by about 5-8% per year, although we often do not see this, because the level of energy consumption is increasing. If the batteries continue to improve at this rate, in twenty years they will be 3-5 times more capacious than today. Other innovations may follow large investments in the battery sector. The joint venture Tesla and Solar City already delivered 55,000 in Kauai to supply most of its infrastructure.
Thousands of powerful lasers will be used to advance the apparatus along with the sail.
The lasers obeyed Moore’s law in much the same way as integrated circuits, multiplying power by half every 18 months. Over the past decade there has been a sharp acceleration in the scaling of the power of diode and fiber lasers. The first struck 10 kilowatts from single-mode fiber in 2010 and a 100-kilowatt barrier in a few months. In addition to raw power, we also need success in combining phased matrix lasers.
Our ability to move fast … moved quickly. In 1804 the train was invented and very soon gained an unheard of speed of 100 kilometers per hour. The spacecraft “Helios-2” eclipsed this record in 1976: at the fastest time, Helios-2 was moving away from the Earth at a speed of 356 040 km / h. After 40 years, the spacecraft “New Horizons” reached a heliocentric speed of 45 kilometers per second (more than 200,000 kilometers per hour). But even if you move at such a speed, it will take a long time to get to Alpha Centauri four light years from us.
Although the acceleration of subatomic particles to near-light speed has become commonplace for particle accelerators, macroscopic objects have not been able to disperse so much. Achieving 20% of the speed of light will be a 1000-fold increase in speed for any object built by man.
The basis for calculations was the ability to store information. Starshot will be dependent on the continued decline in the cost and size of digital memory to provide enough space for storing its programs and images made in the star system of Alpha Centauri and its planets.
The cost of memory has declined exponentially for decades: in 1970, a megabyte costs about a million dollars; Now – a mere penny. The size required for storage also shrank: from a 5-megabyte hard drive, loaded in 1956 with a forklift, to 512-gigabyte USB drives weighing several grams.
Once Starchip takes the pictures, they will need to be sent to Earth for processing.
Telecommunications have progressed significantly since Alexander Graham Bell invented the phone in 1876. The average speed of the Internet today is about 11 megabits per second. The bandwidth and speed required to send digital images within 4 light years – 40 trillion miles – will require the latest advances in telecommunications.
Extremely promising is the technology of Li-Fi, the wireless transmission of which promises to become 100 times faster than Wi-Fi. Also, there are experiments in the field of quantum telecommunications, which will not be fast, but safe.
The last step of the Starchip project will be the analysis of the data returned by the spacecraft. To do this, we will have to rely on the exponential development of computing power, which has increased by a trillion times in the last 60 years.
Reducing the cost of computing recently strongly associated with the clouds. Looking ahead and using new calculation methods like quantum ones, we can expect a thousandfold increase in power by the time Starshot returns data. Such exceptional computing power will allow us to perform complex scientific modeling and analysis of our nearest neighboring stellar system.