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

SpaceX postpones Mars Dragon missions

Based on statements from one NASA official, it appears that SpaceX has put its plans to fly a Dragon capsule to Mars on “the back burner.”

Jim Green, head of NASA’s planetary science division, told Spaceflight Now in an interview that SpaceX has told the agency that it has “put Red Dragon back on the back burner.”

“We’re available to talk to Elon when he’s ready to talk to us … and we’re not pushing him in any way,” Green said. “It’s really up to him. Through the Space Act Agreement, we’d agreed to navigate to Mars, get him to the top of the atmosphere, and then it was up to him to land. That’s a pretty good deal, I think.”

It is my impression that, because NASA has forced SpaceX to give up on propulsive landing of its Dragon manned capsules, the company cannot afford to invest the time and money on it themselves, and thus do not have a method yet for landing a Dragon on Mars. Thus, they must postpone this program.

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.


  • ken anthony

    It looks like SpaceX will probably design a SSTO lander between the size of the Dragon and the ITS. Probably optimized for using the thin martian atmosphere for horizontal flight breaking.

    Which completely destroys one chapter of the book I’m working on! Oh well.

  • pzatchok

    Space X will still have to use the dragon rocket engines for the emergency escape system.
    So they will still be used just not used as a landing system yet.

    NASA plays very safe with everything and it probably just doesn’t want to risk and returning experiments to a landing test.

    But if in the near future there is ever just a returning garbage run I bet Space X argues for a landing test.

    Or if Space X ever has a thrice flown Dragon, a Falcon 9 on its last flight and some spare time and cash……

  • pzatchok

    Unless NASA thinks its just to dangerous to have a fueled ship burn back in.

    And in that case they have to drop back to the old Apollo style needle nose system and throw away 5 million or more in parts on each trip.

  • wodun

    The problem with Red Dragon is that it carries too few people to offer any benefits from scaling. Launching more Red Dragons wont create scaling efficiency. It could work ok for some expensive prospecting missions but everything would be expensive enough to prevent almost anyone but government from participating.

    I am pretty far from being an engineer but it looks to me like each environment needs its own specialized vehicle. What works good for getting off Earth wont work as well in space or on Mars. It could be that in-space transportation could be the limiting factor but also once we can build vehicles large enough to carry thousands of people, will be the enabling factor.

  • ken anthony

    You’re right Wodun, but the bigger problem is the Dragon just doesn’t carry enough fuel for safely landing with little margin for error. The ITS is designed for lower per person unit cost, but it’s absolute operating cost is too high. Thus something mid-sized makes sense.

  • Gealon

    Well, at the very least, it provides more time to include a rover in the package delivered to the Martian surface when and if it does fly.

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