To read this post please scroll down.

 

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.
 

3. A Paypal Donation or subscription:

 

4. Donate by check, payable to Robert Zimmerman and mailed to
 
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652

 

You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.


SpaceX pauses launches after de-orbit of Falcon 9’s second stage misfires

SpaceX today announced that, after its Falcon 9 rocket had successfully placed two astronauts in orbit in its Freedom capsule, the engine burn designed to de-orbit the rocket’s upper stage in a safe zone in the ocean misfired, and for this reason the company was scrubbing a planned launch today until the root cause was found.

After today’s successful launch of Crew-9, Falcon 9’s second stage was disposed in the ocean as planned, but experienced an off-nominal deorbit burn. As a result, the second stage safely landed in the ocean, but outside of the targeted area.

We will resume launching after we better understand root cause

The company provided no further details on exactly what happened. We know the engine fired, and the stage was successfully de-orbited safely over the ocean, but we do not know how far outside its target zone. Nor do we know the extent of the “off-nominal deorbit burn.”

At present today’s scrubbed launch, placing three satellites of Starlink’s competitor OneWeb into orbit, is scheduled for tomorrow, but that is likely a contigency scheduling. SpaceX’s launch teams have gotten very good at rescheduling launches day-to-day, so that as soon as it gets the go-ahead it can go ahead.

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

8 comments

  • Robert Pratt

    You mean SpaceX would stop and investigate something that threatens its success or creates big liability without a government bureaucrat regulator telling it so to do?!

  • Doubting Thomas

    Robert Pratt – Great observation. Enjoy your podcast.

    I wonder how large an area makes up the target area?

    As these things go, I bet there is an additional buffer zone around that target area. I wonder how big that buffer zone is and did the second stage (or debris as it comes in at reentry speeds) land outside the target area BUT INSIDE the buffer zone?

  • Jeff

    “I wonder how large an area makes up the target area?”

    Some recent thoughts on NSF (with graphics):

    https://forum.nasaspaceflight.com/index.php?topic=59683.msg2628588#msg2628588

  • Doubting Thomas

    Jeff – Thanks. Great info. Looking at the site here is what I get out of it.

    Looks to me like the target area was a rough rectangle about 900 nautical miles long and 150 nautical wide (each degree of latitude is roughly 60 nautical miles). Speaking as a guy that used to sail Navy ships around the oceans, that is a pretty big area.

    Talking text boxes on site speculated that, after imperfect reentry burn, second stage fell somewhere between northern end of box and equator or (AT MAXIMUM) about 750 miles outside the area. I would think SpaceX has more precise impact data, but they are under no obligation to share with general public. I am sure that they are sharing with FAA, NASA and DoD (as any responsible US launch provider would).

    Based on the recent discovery that pieces of the Dragon Trunk survived reentry causing SpaceX to shift future landing areas to the Pacific to avoid trunk pieces North America land impact, i wonder how intact the send stage of Falcon 9 is at ocean impact?

    Thanks for great pointer.

  • Ray Van Dune

    Something I’ve been wondering about re promoting the complete incineration of reentering expendable stages: would inducing a longitudinal axis spin promote better incineration?

    Yes: a rapid enough spin might promote the breakup of the stage during reentry stress, creating multiple smaller fragments more likely to completely incinerate.

    No: a spin might tend to more evenly distribute the plasma heating, resulting in fewer extreme hotspots, and promote the creation of larger fragments more likely to survive.

  • Doubting Thomas

    Ray – I have always thought that break up of a stage would induce scattering of pieces over a wider area, some of which would probably survive. I had thought that if an object could reenter fairly intact over the ocean it would reduce the probability of interaction with aircraft of ships over or on the ocean and would just slam down in a single spot under the big ocean / small object theory of safety.

  • Andi

    Minor edit in penultimate paragraph: “we know the extent of”

Readers: the rules for commenting!

 

No registration is required. I welcome all opinions, even those that strongly criticize my commentary.

 

However, name-calling and obscenities will not be tolerated. First time offenders who are new to the site will be warned. Second time offenders or first time offenders who have been here awhile will be suspended for a week. After that, I will ban you. Period.

 

Note also that first time commenters as well as any comment with more than one link will be placed in moderation for my approval. Be patient, I will get to it.

Leave a Reply

Your email address will not be published. Required fields are marked *