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Directed Energy for Relativistic Interstellar Missions

laser sail adrian mann

Rendition of a laser propelled sail (A. Mann)

DEEP-laser sail

Laser propulsion  (Q. Zhang)

1/4-Scale 19 Element Phased Array with 7 central elements activated and Hexapod from PI - Front View
1/4-Scale 19 Element Phased Array with Hexapod from PI
1/4-Scale 19 Element Phased Array with 7 central elements activated - Bottom View
1/4-Scale 19 Element Phased Array with 7 central elements activated - Front View

Since the beginning of spaceflight, humans have accomplished wonderful feats of exploration and showcased their drive to understand the universe. Yet, in those 60 years, only one spacecraft, Voyager 1 (launched in 1977) has left the solar system. As remarkable as this is, humans will never reach even the nearest stars with out current propulsion technology. Instead, radically new strategies involving the technology already available must be used.

We propose a roadmap to a program that will lead to sending relativistic probes to the nearest stars.

To do so requires a fundamental change in our thinking of both propulsion and our definition of what a spacecraft is. In addition to larger spacecrafts capable of human transportation, we consider “wafer sats”, wafer-scale systems weighing no more than a gram. The wafer sats would include integrated optical communications, optical systems, and sensors. These crafts, combined with directed energy propulsion, could be capable of speeds greater than 0.25 c.

This program has applications for planetary defense, SETI and Kepler missions.

List of our recent Directed Energy related publications: DE_STAR_and_related_References

An online photon propulsion calculator is available Here.

Witches Broom by Ken Crawford 5 fitler image

Array and Hexapod Demonstration

May 2016 – FY 2017 NASA budget request includes Alpha Centauri relativistic mission study

FY 2017 NASA appropriation request – Science

Amy on the Radio – May 22, 2016

Photonic Propulsion for Interstellar Flight

NPR – May 10, 2016

Are we about to send Spacechips to the Stars

Breakthrough Starshot Announcement – April 12 – 2016

Official Webpage for Breakthrough Initiatives
Articles by Scientific American, Wired, Popular Science, and The Economist

Breakthrough Interview on Photon Propulsion

What makes photon propulsion feasible

Video Interview with TIME Magazine – Nov 7, 2015

Time – Inside the Plan to go to the Stars

Recent Publications

A Roadmap to Interstellar Flight – Lubin – submitted April 2015 to JBIS

JBIS Vol 69, Pages 40-72, Feb 2016

A Roadmap to Interstellar Flight

SPIE Optics + Photonics – San Diego – August, 2016

Madajian et al. “LAST: Laser Array Space Telescope”: Paper

Srinivasan et al. “Stability of laser-propelled wafer satellites”: Paper

Lubin et al. “Implications of Directed Energy for SETI”: Paper

Brashears et al. “Building the future of wafersat spacecraft for relativistic flight”: Paper

Kulkarni et al. “Relativistic solutions to directed energy”: Paper

Directed Energy for Relativistic Propulsion and Interstellar Communications – from Aug 2013 ICARUS Starship Congress submitted Jan 2014- Journal of the British Interplanetary Society (pub JBIS 2015 68, 172) – Lubin et al 2015 DE-STAR-JBIS – v13

As published: JBIS – as published – black-white – Lubin

SPIE Optics and Photonics – San Diego – August 2015

Zhang et al. Orbital simulations of laser-propelled spacecraft

Brashears et al. Directed Energy Interstellar Propulsion of WaferSats

Research Mentorship Program – UCSB – Summer 2015

Sturman et al. “Interstellar Flight and Recycling Light: a Bilateral Study”: Paper, Poster

Li et al. “Optimization for Laser-Propelled Spacecraft at All Launching Times”: Paper, Poster

Centauri Dreams – Beaming WaferSats to the Stars – June 25, 2015

February 2016 – NASA 360 Video on Interstellar NIAC Results


Watch it on Facebook

Watch it on YouTube

YouTube NASA 360 Channel

Video from NASA 360

NASA NIAC Fall Symposium – Seattle – October 2015

NASA NIAC June 2015 announcementUCSB Current Article

Audio Interview with the Tennessee Valley Interstellar Workshop 2015

Keck Institute for Space Studies (KISS) 2014 Workshop on “Science and Enabling Technologies to Explore the Interstellar Medium” – final reportFinal KISS ISM Report

SPIE Optics + Photonics – San Diego – August, 2014

Hughes et al. Optical modeling for a laser phased-array directed energy system

SPIE Optics + Photonics – San Diego – August, 2013

Lubin et al. Directed Energy Planetary Defense (plenary)

Hughes et al. DE-STAR: Phased-Array Laser Technology for Planetary Defense and Other Scientific Purposes

Bible et al. Relativistic Propulsion Using Directed Energy

Plentary talk (45 min) by P. Lubin:


SETI Institute lecture– February 2014

SETI Big Picture Science Radio Show Interview: Space For Everyone: Philip Lubin by Niederhoff

Lecture – Presentation: Directed Energy for Planetary Defense and Implication for Searches for Advanced Civilizations

Example of Spacecraft Propelled by Laser
Consider a 10 g payload attached to a 2 m diameter sail (left) and a 1 g payload attached to a 0.7 m sail. The bare spacecraft mass is equal to the sail mass (right). In this example of a small system the laser array propelling the craft has an optical power of 272 kW and is 20 m diameter. The laser and craft both start in low Earth orbit. The array remains in low Earth orbit while the craft is slowly propelled away, spiraling outward from the Earth. The following simulation shows the trajectory of the craft over the first week of propulsion while still in Earth orbit. The craft will ultimately leave the Earth orbit completely in both cases. The left side is an optimized solution while the right is un-optimized for comparison
Orbital Simulation of Laser Propelling a Spacecraft

Funding for this program comes from NASA grants NIAC Phase I DEEP-IN – 2015 NNX15AL91G and NASA NIAC Phase II DEIS – 2016 NNX16AL32G and the NASA California Space Grant NASA NNX10AT93H as well as a generous gift from the Emmett and Gladys W. fund.

The richness of the interstellar medium from the sun to the nearest stars (Keck Institute for Space Studies)


Local stellar system - IBEX - 619253main_D3-Clouds-Astrospheres

Stars and exoplanets within 25 light years of the Sun (NASA/Goddard/Adler/U. Chicago/Wesleyan)