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

Chandra looks back at the Crab Nebula

Link here. It is almost twenty years since the Chandra X-Ray Observatory was launched, and in celebration the science team have released another X-ray image of the Crab Nebula, taken in 2017 in league with an optical image from the Hubble Space Telescope and an infrared image from the Spitzer Space Telescope. They have also provided links to all similar past images, going back to 1999.

Some of the images are actually videos, in 2002 and 2011, showing the Crab’s dynamic nature. You can actually see flares and waves of radiation rippling out from its center.

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.


  • Max

    Beautiful picture, the combination of the different wavelengths of light give us a more complete understanding of how different stars work.
    The illustration shows that they believe the Jets do not emanate from the rotational center. Perhaps Local Fluff can weigh in and give his thoughts on whether the bent jet is because the star is moving, or the void in The energy cloud could be caused by local fluff pressure blowing and moving the energy away from the star?

  • Localfluff

    I’m not a real astronomer! I just copy what some of them say. Misunderstandings and selectivity is my value add proposition.

    The local fluff (30 light years) is a puff of gas and stuff ejected by active young stars in the Scorpius–Centaurus Association (400 light years) surrounding the Sun in the local bubble is much smaller than the distance to the Crab Nebula (7000 light years).

    I would guess that the bending of the jet stream in that fantastic imaging of a real neutron star (such an extreme object, such an extreme form of matter!) is not caused by gravity. Rather by precession of the rotational axis of the neutron star out of which poles the jets are streaming, or radically changing magnetic fields. Neutron stars can have hard enough magnetic fields that chemistry ceases to exist in its vicinity. When all the electrons’ orbits around the atom nuclei follow parallel force field lines, no chemical interaction is possible (I think). Whatever is local to it, is not similar to the harmless gas fluff around our garden here in the Sun.

    Neutron stars are more interesting than black holes, because they exist in our universe and can be observed. They consist of real matter, and they are so weird. Like, you see both poles at the same time because the spacetime of its surface is so curved. A geometrical challenge for map projection geographers.

  • Localfluff

    Or the jet’s redirection is maybe caused by a moving very angry “sun spot” on the neutron star without changing its rotational axis (which I imagine would require alot of external energy). The jet might be like a super sun spot active region on the surface of the neutron star. Created by forces in its so called “strange star” kernel (named after the strange quark, as in a quark star, not because it is strange because it already was very strange anyways) that might exist in its relativistic quantum mechanic innerness near the spacetime horizon. It has been suggested that some neutron stars exist only thanks to their high rotational speed. As they slow down they collapse to black holes because the decaying centrifugal force (due to magnetic field interactions) one day doesn’t keep it above the limit of total mass collapse, and the magician suddenly disappears.

  • eddie willers

    It’s a wizard’s hat.

    (nec divinos petasum)

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