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The Israeli astrophysicist's journey to Proxima Centauri

Prof. Avi Leib from Harvard University says in an interview with the Hidaan website that one should invest in risky projects in science like a venture capital fund invests in risky ventures, if they succeed they will return the investment several times

Physicist Stephen Hawking, and behind him investor Yuri Milner (left), Freeman Dyson and Avi Leib at the announcement of the STARSHOT project in New York in April 2016. PR photo
Physicist Stephen Hawking, and behind him investor Yuri Milner (left), Freeman Dyson and Avi Leib at the announcement of the STARSHOT project in New York in April 2016. PR photo

 

More of the topic in Hayadan:

A terrestrial planet has been discovered around Proxima Centauri, the closest star to the Solar System

Is there life on the nearest planet, Proxima Centauri b?

Stephen Hawking and Mark Zuckerberg are aiming for the stars

The triple star system Alpha (A and B) and Proxima Centauri, the first two of which are similar to the Sun and the third a red dwarf, is in the spotlight for containing the star most similar to Earth possible, Proxima b, which researchers from the European Southern Observatory reported this week in the journal Nature.
Prof. Avi Leib, an Israeli researcher at Harvard University and the Harvard Smithsonian Institute, said in recent days that if it turns out that the new planet, or any other planet in the Proxima Centauri system is suitable for life, there is a chance that it could serve as a home for humanity when the Earth is hostile to life. It would be worthwhile to do this even if the science takes generations.
Humans may have trouble getting there quickly, but there is no reason why information cannot be gathered from there and transmitted to Earth in a reasonable amount of time. This is what Prof. Leib, who serves as a scientific advisor to the Breakthrough Starshot project, is dealing with, which wants to send a fleet of tiny spacecraft to this system to photograph and study the system.

Even if it is a neighbor, the journey there with the technology that exists today will require tens of thousands of years. There are those who would like to see it in their lifetime. This man's name is Yuri Milner, who in July 2015, about a year ago, announced Breakthrough Initiatives - a scientific program to research the fundamental question of life in the universe. He announced the initiative at a conference of the British Royal Society in London in the presence of Stephen Hawking, Martin Rees, Frank Drake (the developer of the famous formula for estimating how many life-bearing planets there are in space), Jeff Marcy and van Druyen, Carl Sagan's widow.

The initiative consists of two sub-initiatives: one is Breakthrough Listen - to increase listening for the detection of signals from intelligent aliens, and the other - which is managed by Pete Warden, former director of NASA's Ames Center in California - Breakthrough Starshot - launching tiny spacecraft to the Alpha Centauri system to investigate it and if there is any Planets around him (as it was discovered now, a year after they started the project) also to photograph them.
Worden recently lectured on this as part of the Space University held at the Technion (an article about it soon), and he is the one who recruited the scientific director of the project, Prof. Avi Leib from Harvard University.
It should be noted that the interview with Prof. Leib also took place before the current discovery. Leib started his career as part of the Talfiot project where he served at MMG in Nahal Sorek, where he proposed together with an experimenter named Zvi Kaplan, later head of MMG and later as director of the Israel Space Agency, a project for electromagnetic propulsion to accelerate masses to high speeds.
"I really wanted to engage in research instead of engineering or supervising technological work, which was what was accepted. When I arrived at Nahal Sorek, Israel participated in the development of "Star Wars". We received a significant amount from the USA and established a new division at MMG in which I was responsible for the theoretical side and Kaplan for the technological side."

"Since the project was joint, we visited Washington every few months, and at one of the conferences where we presented our work, someone suggested that I visit the Institute for Advanced Studies in Princeton where Einstein worked at the end of his days and offered me a position there instead if I switched to astrophysics. I then had a year left to finish the eight-year commitment (three years of mandatory service and then work at the MMG)."

In the end, Leib settled at Harvard University and the Harvard-Smithsonian Institution, reaching senior academic positions.

"Starshot is the closing of a circle because I started with a practical project that was successful and then I researched the field of astronomy and now the new project combines the two fields of knowledge that I dealt with."

The story started about a year ago when Yuri Milner and Pete Worden - the head of NASA's Ames Center in California finished his position and Milner recruited him for the position. They both came to my office in Harvard in May about a year ago to convince me to join Frutech. They had a number of projects they were thinking about and finally in July of that year we announced the project to search for alien signals. Before we announced the Breakthrough Starshot project I wanted to do a feasibility assessment. The idea was to launch spacecraft there that would touch the neighboring planet in our lifetime. Since the distance to Alpha Centauri is 4.4 light-years, it would take one-fifth the speed of light to get there in 20 years.
I recruited 12 people around me and for six months we tested all the ideas proposed in the literature and we also tested new ideas and we came to the conclusion that the best way to reach such speeds is to push with strong radiation a sail that is connected to a phone that contains a camera and communication components. "
"The ability to miniaturize electronics today makes it possible to build such tiny spaceships, something that could not even be dreamed of ten years ago, however, it has not yet been used in space. The idea is to miniaturize the system to the gram scale. An iPhone without the shell that protects it weighs about a gram. It is possible to minimize the entire electronic system to this size, including cameras, communication components and everything needed to send such a spacecraft into space, while in the past all the systems sent into space weighed much more - by orders of magnitude."

"The possibility of building interstellar spaceships was examined in the past, but it was found that in order to implement it, a nuclear fusion engine is needed, a technology that has not yet been demonstrated even in a laboratory. Since the propulsion system is a very heavy component in the spacecraft, to reach a speed of 20% of the speed of light it is necessary to leave the fuel behind."
"If you push a sail with the help of light, you can reach a speed that is close to the speed of light and the energy system remains on Earth. A powerful laser, and here too there was a technological development: small lasers can be connected to a powerful system - many lasers that direct their beams. This is a technology developed for combat systems - it was demonstrated recently."
"At the end of December 2015, I stayed with my wife at goat farms in the Negev (proper farms) near Sde Boker. Warden called me there and asked to hear a report within ten days. I agreed and wanted to make a presentation but when we got to the farm it turned out that only the office there had an internet connection. At six in the morning I sat with my back to the office and looked at the goats and wrote the presentation to Yuri Milner."
"Ten days later I gave the presentation at Milner's house in California to a group of people that included astronomers who were enthusiastic about the idea. After that, discussions were held for several months and Milner asked difficult questions and examined the risks in a matter-of-fact manner."

"Until in the end he agreed that the project should be announced publicly, and then on April 12 - Yuri's night, named after Yuri Gagarin, who Milner was also named after because he was born a few months after Gagarin's launch, the heads of the project arrived, including Milner and Hawking, and with them Live for the announcement On the roof of the World Trade Center tower. The event was broadcast on fifty television stations, and it was also attended by Freeman Dyson, the physicist who in the XNUMXs proposed detonating small nuclear explosions behind the large spaceship, in order to accelerate its speed and in what was then called Project Orion (as opposed to the current project of that name, which is used for NASA's next manned spacecraft A. B).

The way it is organized - there is Pete Warden the general manager, I am in charge of an advisory committee which is the committee
At this point I am the head of the Department of Astronomy at Harvard and also the head of the Institute for Theory and Computing, I also run the Hawking Institute for Black Hole Research, and STARSHOT is the fourth hat. I don't think I will give up STARSHOT and the management of the other institutes, but I may give up the permission of the department.

Can the spaceships be slowed down when they get to Alpha Centauri?

"It is impossible to stop or slow down, the only way to stop them is to install a similar laser system in the target system, which is obviously not applicable. It is actually a projectile that moves at a constant speed and will continue to move forever. However, the price of the components that will be sent to space is very low, on the order of tens or hundreds of dollars per unit, so it is possible to send many of them. The main cost is building the laser system for launch, which can reach 10 billion dollars, which is already the order of magnitude of Saran or the James Webb Space Telescope."
"But as soon as the system itself is built, the launch itself is very cheap and then it is possible to send a spacecraft every day when the launch area heads towards the Alpha Centauri system. Devices can be installed in each spaceship that will be used for different purposes. It is also possible to send spacecraft throughout the solar system itself, for example spacecraft that will collide with bodies in the solar system and send close-up images, a spacecraft that will pass through the gas jets in Enceladus that will allow us to know the composition of the underground ocean and whether there is life on it. Since they move at a fifth of the speed of light, the time it will take them to reach Pluto, for example, is three days instead of the nine and a half years that New Horizons took. If the ninth planet exists it could be another target.”
And of course it is also possible to go further to a distance of 550 astronomical units and use the sun as a gravitational lens. It will be possible to place on Mars a projectile similar to the one on Earth and the colonists there will be able to send packages that will arrive on Earth within a day.

How would such a tiny spacecraft transmit from a distance of four light years to Earth?
The idea is to use a laser transmitter. Communication using lasers is a fairly new field of research and has a promising future. The idea is to install a XNUMX watt laser on the spacecraft. We checked the numbers - if you build a system large enough to receive the signals on Earth, it will be possible to communicate with the spacecraft and receive images or other data from them.
We compiled a list of about twenty risks and in the first years of the project we will test the programming and test each of these risks, to see how to solve the challenge that involves this risk. One of the most important risks is communication.
Milner allocated one hundred million dollars to the project in the first years to test the programming, and if it seems feasible, he will try to raise the rest of the money for the construction of a larger system. The personal risk I am taking is not great, although it is a project of the order of 30-20 years that will occupy me for a long time but will not prevent me from conducting scientific research at the same time.

"In a lecture at the Breakthrough Award conference in May of this year, I explained that young scientists should diversify their investments in research. To have a sufficiently diverse investment portfolio that contains risks similar to a venture capital fund and to invest 20% of the research in high-risk research, and a third of the time in safe things. The rest of the time can be invested in projects with different degrees of risk. The problem I see at the moment is that most young people invest in safe things because those who do research on the conventional path receive encouragement from the mainstream. In my career I have always taken risks and my conclusion is that it is difficult to make extraordinary discoveries and breakthroughs if you do not take risks. Just like in business."

8 תגובות

  1. A few questions: 1. In terms of the spaceship's time, the journey time will not be 20 years, but much shorter, does this mean that after a generation of years in terms of the Earth of the gift, the spaceship will have less than a minute to photograph the planet before flying away from it?
    2. Is it not possible to rotate the spaceship? A little normal fuel that will only be used for a turning radius and then allow her to slow down when she returns to Israel using the same lasers that accelerated her?
    3. Can't such a fast slingshot be used to penetrate Europa's ice sheet?
    4. Why do you need to enter the URL that you are responding to? It's very difficult to respond like this from a mobile phone. Maybe make a mobile app?

  2. "It will be possible to place on Mars a projectile similar to the one on Earth and the colonists there will be able to send packages that will arrive on Earth within a day."

    Come on, what packages can you send that weigh one gram? If anything, it is better to send a data file that will define for the 30D printer on the other side which product to print. In XNUMX plus years they already knew how to print almost anything, if not everything.

  3. singularity,

    The laser should only push the spacecraft for a few minutes, as soon as the spacecraft reaches maximum speed it continues on its own with the force of inertia, like an asteroid flying in space, most of the journey is without a laser push.

    And yes, until we get the first photographs it will probably be at least 25 years.

  4. How do you overcome the problem of distortion / dispersion of the laser beam at such distances?
    And what about disturbances such as dust?
    You forgot to mention that even if the project starts, it will take 4 years for the communication from the tiny spacecraft to reach the earth

  5. If that's how you can launch spores there on top of a laser beam, and by the time humans get there in a few tens of thousands of years, there will already be primitive life forms there.
    And maybe that's how life on Earth was created.

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