Investor Yuri Milner will invest $100 million in the project of a flight to Alpha Centauri. For this purpose, a ship will be built capable of reaching a speed of 160 million km/h. In an interview with RBC, Milner spoke about the details of the interstellar project

Investor Yuri Milner (Photo: Bloomberg)

— Why do you want to build a nanoship and not an inhabited starship, for example?

“When people imagine interstellar travel, they see it something like in Star Wars: a huge ship flying through some kind of wormhole at the speed of light, on which a lot of interesting things happen. But this topic is impenetrable in advance, because it is impossible to speed up a thing of such a huge size. Even with the availability of energy sources that we do not yet have.

What is the main problem of interstellar travel - there was no engine that would be adequate for the tasks. People thought about thermonuclear energy, antimatter, there are only three or four options. One of them is a photonic solar sail. The problem with all other options is that we simply do not have the scientific basis. We cannot yet, even on earth, use thermonuclear energy, it is not possible yet, and we have no idea where to get so much antimatter, where to store it, and so on. We run into fundamentally scientific problems.

There were no fundamental scientific problems with the sail, there were technical problems: the sail itself and the entire spacecraft were always very heavy. And it is unclear where to get so many photons, and the sun is not enough for this. The whole topic was at a standstill, and it was believed that for several hundred years there was no need to worry about it.

- What has changed now?

- The solution to the problem lies in an unexpected direction, namely: let's make the spaceship very small. So small that it will weigh a few grams or one gram. We will also make a very light sail. And if this can be done, the problem becomes fundamentally solvable. And why it succeeds is because the last 15 years have seen advances in microelectronics, which have mostly been applied to mobile phones and other devices.

Let's take a camera - over the last ten years it has become 100 times cheaper and approximately 100 times smaller in size. On Amazon you can now buy a camera for $10, which will weigh a few grams. This happened not only with cameras, but also with other devices that should be on any self-respecting spacecraft. Mini engines that run on photons, batteries, navigation equipment. All this, according to our analysis, can be done within one gram - cumulatively.

— When can such a device be built?

— The device can be made today, there is no need to wait 20 years. The most complex part is the photon engine, the laser complex - this is far beyond what we can do today. But on the other hand, this is a question of scaling. The idea is that in order to make this project, nothing new needs to be invented, everything has been invented over the past 15 years. We take the latest achievements and try to scale them up and apply them specifically to astronautics. The application of Moore's law to astronautics is a fresh idea, it seems to me.

— Do you have an idea of how many years it will take to implement the project?

Unfortunately, there is no such understanding, as in any large project. We say that, in principle, such a project can be implemented within the lifetime of one generation. Still, going beyond the solar system has been a long-standing dream of humanity, and the fact that we can, in principle, realize it is no longer trivial.

The first stage is research, the second is a prototype. As for the ship, I have no particular doubts. Next in complexity is the sail; here additional research will be needed. Well, the most difficult part is this laser design. Of course, we can show some results, we can do trial runs, and so on. I think this is not a discrete project, but a gradual one. You can’t immediately move to a speed of 100 million km/h, you can gradually. The main thing is that this can be done - it’s just ordinary physics, there can be no debate here.

But if you send something somewhere into the Universe, everyone needs to agree among themselves. And this requires building some kind of global consensus, and this too may take 20–30 years to simply agree on. Even if we prove that this is technically possible, the next question is: will the public support us, you know? (laughs)

Yuri Milner - RBC: “Let's make a spaceship weighing one gram”