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NEW - SEPT. 2023:
Alone But Not Lonely, Exploring for Extraterrestrial Life
Univ. of Arizona Press
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June 13 - Book talk at Adventurers Club, Los Angeles

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- Handbook of Bioastronautics
Chapter Author: Humans and Robots in Space Exploration
- Space Science and Public EngagemenChapter Co-author: Crowdfunding for Space Science
100 Year Starship Canopus Award Anthology, Roald Publishing LLC, 2023; Chapter - Finding Earth 2.0 from the Solar Gravity Lens Focus, with S. Turyshev 
- CScientific American Essay:  about cooperating with Mars sample return exchanges 


Current work
Into Interstellar Space:

With Slava Turyshev of JPL and a team from JPL, Aerospace Corp., UCLA, Xplore Inc. we are studying a mission to use the 100 billion magnifying Solar Gravity Lens (SGL)  to get high-resolution images of habitable planets around other stars.  To do this we must reach the focal line of the SGL which begins at 547 AU from the Sun and extends toward infinity.  This requires: a very fast spacecraft ~ 20 AU/year, which we get with a new solar sail/ smallsat design invented by Darren Garber (NXTRAC) and Nathan Barnes (L'Garde).

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The solar gravity lens is formed by the bending of light by the gravity of a heavy object-- in this case the Sun.  This was predicted by Albert Einstein in 1916 and observed by Sir Arthur Eddington in 1919. The convoluted image is formed in an "Einstein Riing" and must be deconvoluted.

The interplanetary smallsat sailcraft mission design creates a new paradigm for access to the solar system from inside Mercury's orbit to beyond the Kuiper Belt.  We are now studying new mission concepts such as a close solar polar orbiter, Europa and Enceladus fly-throughs, and fast scout missions to Uranus and Neputne.


To Explore New Worlds and Seek Other Life:

This was why Carl Sagan, Bruce Murray and I formed The Planetary Society.

  • What is our place in the Universe?

  • Are we alone — is life in the Universe iniquitous or unique?

  • Will humankind become a multi-planet species or be limited to Earth?

  • How will Earth and Life evolve:  in cooperative symbiosis or with mutually assured destruction?


The Planetary Society was founded in 1979  as a non-profit, public interest organization to advance3 planetary exploration for all people of Earth.  We promoted interational cooperation on space missions , working closely with space agencies in the U.S. (NASA), the Soviet Union (and later Russia), Europe (particularly the European Spce Agency and the Centre National d'Etudes Spatiales, Japan (ISAS and JAXA) and with citizens around the world.  Among our notable achievements were:

- introducing rovers into the NASA program with our international Mars Rover test program

- advancing international cooperation in space science including on the UN Committee on Peaceful Uses of Outer Space

- first privately funded payload experiment to another world - the Mars Photonics Experiment on Pathfinder

- the first library on Mars:  Visions of Mars on the Phoenix mission

- and the successful privately funded LightSail mission in Earth orbit

Today The Planetary Society is led by Bill Nye who succeeded me as CEO when I retired in 2010.

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In 2020 The Planetary Society celebrated its 40th anniversary.  With its innovative projects, political advocacy and international cooperationnn we have seeded new exploration of the solar system. 


Depicted here is LightSail in orbit over the Earth -- a privately funded mission pioneering a new way into the solar system and beyond.  Remarkably the sailcraft has continued to work in orbit for over two years, showing that even smallsats, thin sails, and creative non-government teams can accomplish great things.  Kudos to all on LightSail, especially the spacecraft builder Stellar Exploration and the operations team at California State University - San Luis Obispo. And thanks to all the private donors to The Planetary Society who made it happen



  M  A  R  S 


 is the only world humans can reach with atmosphere and water; on it will be determined how humankind will evolve as a multi-planet species.  Three possible ways (hover over images for description). 

In 2020 three new missions to Mars were launched from Earth: Mars 2020 from the United States, Tianwen-1 from China,  and Hope from the United Arab Eremites  joining five spacecraft already there.   See a list of all Mars missions; past, present and future.  A fourth mission from  Europe and Russia was planned, but is now delayed to 2022.  Following the launches of the three missions in July 2020, I was asked to give a presentation about them to a general audience -- this is it.  

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