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Readers!

 

My July fund-raising campaign to celebrate the fifteenth anniversary since I began Behind the Black is now over. I want to thank all those who so generously donated or subscribed, especially those who have become regular supporters. I can't do this without your help. I also find it increasingly hard to express how much your support means to me. God bless you all!

 

The donations during this year's campaign were sadly less than previous years, but for this I blame myself. I am tired of begging for money, and so I put up the campaign announcement at the start of the month but had no desire to update it weekly to encourage more donations, as I have done in past years. This lack of begging likely contributed to the drop in donations.

 

No matter. I am here, and here I intend to stay. If you like what I do and have not yet donated or subscribed, please consider supporting my work here at Behind the Black. You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:

 

1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.

 

2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
 

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August 22, 2025 Quick space links

Courtesy of BtB’s stringer Jay, who apologizes for the lateness due to a hectic day at work. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

 

The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.


The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
 

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

6 comments

  • Milkman

    Well, They did not steal that 1st stage landing technique from SpaceX.

  • John

    Starship technical update 6pm EST (maybe? IIRC the last one was not held) before launch this evening.

    https://x.com/i/spaces/1PlJQOWdmrkKE

  • Jeff Wright

    There has been some talk of having Starship land on the Moon in a prone fashion. DTAL was to be similar.

    I imagine they want to test that by landing a booster that would be of similar size as their later Starship clone.

    If they stick the landing with Earth’s stronger gravity, lunar landings should be a cinch.

  • Edward

    Jeff Wright,
    You wrote: “There has been some talk of having Starship land on the Moon in a prone fashion.

    Was that talk coming from SpaceX or from others?

  • mkent

    ”If they stick the landing with Earth’s stronger gravity, lunar landings should be a cinch.”

    That’s not how it works. The tipping force is six times stronger on the moon than it is on Earth.

  • Edward

    mkent,
    Your comment reminds me that there are other factors that complicate landings. ULA’s plans for reusability of its Vulcan does not bring bring back the whole booster, because it has only two engines. This means that the minimum thrust is far, far too large for a safe landing. The “hover-slam” landing of Falcon is also because the thrust of a single Merlin engine is too large for Falcon to hover. Vulcan would have a much worse “hover slam” landing problem than the Falcons have.
    https://www.youtube.com/watch?v=BqJ5bKuApbs#t=1066 (Tim Dodd, “Why does Starship do this?” cued up to my point)

    Starship’s engines are designed to land in Earth’s gravity, which would be too strong in the Moon’s gravity. In addition to that, the thrust from Starship’s engines would kick up dust and rock in a terrible way, possibly digging a hole under the landing legs, making a safe landing unlikely. SpaceX’s solution is to put smaller thrusters high up on the Starship body so that a more modest thrust is used in a way that does not dig out the landing zone similar to the first Starship test flight did to its launch pad (“stage zero,” in SpaceX lingo).

    Landing on the Moon is a tricky proposition, and landing a 100-ton Starship lander does not make it any easier. If the payload of that lander is located a hundred feet high, then the center of mass is also high. With a high center of mass, how level does the landing site have to be for a successful landing, and how much more level must it be for unloading the lander by moving payload outside the footprint as it is lowered to the ground? The center of mass is not only high, but it moves around during unloading and loading.

    Sticking the landing on Earth is relatively easy, because Starship has landed on prepared concrete pads, flat and level. Until there are such landing pads on the Moon, finding a suitable flat and level landing site will be another problem. How much length adjustment can each landing leg do in order to adapt to a non-level non-flat landing site?

    The ability for the human pilots to hover, in order to find a suitable landing site, was one of the ways that the Apollo Lunar Modules (LM) were successful in landing on the Moon. How long can a Starship hover while finding a suitable landing site? These LMs were able to successfully launch back to space with a tilt of up to 12°. What kind of tilt is allowable for a safe launch of Starship from the lunar surface?

    Another way they were successful is that they could still have some amount of horizontal motion across the terrain at the moment of landing, but this was a problem for several of the recent unmanned lunar landers. With a high center of mass, this would also be a problem for Starship, making it harder for the craft to search for a suitable landing site. They would have to take the time to completely stop before setting down.

    If Starship lands in a prone fashion, many of these problems are vastly reduced in magnitude, and offloading requires a much reduced descent by elevator, or maybe it can be done by a ramp instead of the complicated mechanism of an elevator.

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