Leaving Earth cover

In 2019 I obtained from my former publisher the last 30 copies of the now out-of-print hardback of Leaving Earth. I sold about half of these, and with only a handful left in stock I have raised the price. To get your own autographed copy of this rare collector's item please send a $75 check (includes $5 shipping) payable to Robert Zimmerman to

Behind The Black, c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652

I will likely raise the price again when only ten books are left, so buy them now at this price while you still can!

Also available as an inexpensive ebook!

Leaving Earth: Space Stations, Rival Superpowers, and the Quest for Interplanetary Travel, can be purchased as an ebook everywhere for only $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from my ebook publisher, ebookit.


Winner of the 2003 Eugene M. Emme Award of the American Astronautical Society.

"Leaving Earth is one of the best and certainly the most comprehensive summary of our drive into space that I have ever read. It will be invaluable to future scholars because it will tell them how the next chapter of human history opened." -- Arthur C. Clarke

NASA pulls funding from private asteroid hunter

Because of a failure to meet its developmental deadlines, NASA has cut its ties with the privately funded Sentinel satellite, designed to spot 90% of all near Earth asteroids that might pose a threat to the Earth.

The problem for the B612 Foundation, the private company committed to building Sentinel, is that they haven’t clearly laid out a way any investors could make money from the satellite. Thus, they have so far raised only $1.6 million from private sources. They need almost half a billion to build it, according to their own budget numbers.

Pioneer cover

From the press release: From the moment he is handed a possibility of making the first alien contact, Saunders Maxwell decides he will do it, even if doing so takes him through hell and back.

Unfortunately, that is exactly where that journey takes him.

The vision that Zimmerman paints of vibrant human colonies on the Moon, Mars, the asteroids, and beyond, indomitably fighting the harsh lifeless environment of space to build new societies, captures perfectly the emerging space race we see today.

He also captures in Pioneer the heart of the human spirit, willing to push forward no matter the odds, no matter the cost. It is that spirit that will make the exploration of the heavens possible, forever, into the never-ending future.

Available everywhere for $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from the ebook publisher, ebookit.

One comment

  • PeterF

    This is sad news for the B612 foundation but not necessarily that bad to people who think that Near Earth Objects are the second biggest threat to all life on earth. (The first being our local star experiencing an “end of life” event.)

    NASA had only agreed to provide analysis and data downlink for this project.

    Perhaps now that they won’t be chasing tax dollars they will find a new efficiency. With the advent of competitive commercial launch services slashing the on-orbit cost, I predict the era of satellites costing hundreds of millions of dollars will be coming to an end. (unless of course they are taxpayer funded)
    The current cost is driven mainly by the desire to trim all extraneous mass so that every gram of material performs at least one critical function. The George Washington bridge would have been a different sort of incredible engineering feat had it been designed using the same paradigm. But then they would not have been able to add a second roadbed.

    My point being, If B612 is not constrained by the cost of lifting excess mass they could probably have any university engineering department build the thing for the 1.6 million they have already raised as a senior class project. I know guys that could probably build an operational mock-up in their basement. (then they would probably then discover that it wouldn’t fit out the door)

    Frankly, I’m surprised that NASA had not implemented a similar satellite program themselves considering congress passed legislation requiring them to locate 90% of all NEOs 140 meters or larger. I suspect the decision to comply with the law using mainly ground based assets was driven by a combination of bureaucratic territorialism and current program budget constraints. A pity because public awareness of the danger posed by NEOs seems to be renewed every few years and that interest drives approval for budget increases.

    Please, Please, PLEASE don’t let this posting devolve into a NASA bash like the Dark Streaks posting did.

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