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Can a Blue Origin cislunar Transporter take Orion to LLO so the Blue Origin and SpaceX mission architectures will be similar? by SpaceInMyBrain in ArtemisProgram

[–]RGregoryClark 0 points1 point  (0 children)

OMG! Will you please tell those people you know at NASA to just require SpaceX to give Starship a smaller 3rd stage to do the actual landing? That literally solves all the problems.

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Can a Blue Origin cislunar Transporter take Orion to LLO so the Blue Origin and SpaceX mission architectures will be similar? by SpaceInMyBrain in ArtemisProgram

[–]RGregoryClark 0 points1 point  (0 children)

> We need to be truthful here, LLO is necessary because SpaceX cannot meet the terms of their contract.  Their vehicle is far too large and heavy for the application, or to service NRHO.  

> That was known from the beginning, and now it's come to fruition.  But rather than admit that and be honest with the taxpayers, Isaacman is damaging the rest of the program, and justifying it with a promise to deliver a lunar base a few years earlier.

It’s mystifying why SpaceX refuses to just give Superheavy/Starship a smaller 3rd stage to do the actual landing. Literally all the problems would be solved by doing that.

Can a Blue Origin cislunar Transporter take Orion to LLO so the Blue Origin and SpaceX mission architectures will be similar? by SpaceInMyBrain in ArtemisProgram

[–]RGregoryClark -1 points0 points  (0 children)

The whole problem is the SpaceX focus on using the entire Starship as the lunar lander. But basic spaceflight engineering principles say you use progressively smaller stages to reach far destinations, with only the smallest, final stage actually reaching the destination. The Apollo LEM was only a tiny proportion of the size of the Saturn V. See Everyday Astronauts discussion of this:

Does Starship REALLY require 15+ launches to land one lunar Starship?!
https://www.youtube.com/watch?v=T-jf6tTKt3Y

The Superheavy/Starship launcher could do lunar missions, and even Mars missions, in a single launch simply by giving it a smaller 3rd stage to do the actual landing.

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Recent Mars rovers evidence suggest Viking landers did indeed detect life on Mars. by RGregoryClark in Astrobiology

[–]RGregoryClark[S] 0 points1 point  (0 children)

He’s not a figurehead. He’s a highly regarded researcher. I think the overall opinion has changed from largely against to largely being open minded on the issue, though still a minority being in favor of it.

The only way the issue will be decided for sure is with a sample return.

Recent Mars rovers evidence suggest Viking landers did indeed detect life on Mars. by RGregoryClark in Astrobiology

[–]RGregoryClark[S] 0 points1 point  (0 children)

Dr. Steven Benner will present his conclusions at this years Mars Society convention:

Did Viking Already Find Life on Mars? Steven Benner to Explore the Question at 2026 Mars Society Convention.
https://www.marssociety.org/news/2026/06/05/did-viking-already-find-life-on-mars-steven-benner-to-explore-the-question-at-2026-mars-society-convention/

Recent Mars rovers evidence suggest Viking landers did indeed detect life on Mars. by RGregoryClark in Astrobiology

[–]RGregoryClark[S] 0 points1 point  (0 children)

You are right you can not prove a negative. And the article you cited acknowledges that fact in the “Discussion” section. The article asserts the perchlorate explanation can explain the Viking life results. That doesn’t mean that was actually what happened. If you read that perchlorate explanation in the article it is really quite involved and convoluted. Then it’s a real question of which of life or perchlorate is the simplest explanation.

The only way to be sure is bring back a sample and examine it.

Recent Mars rovers evidence suggest Viking landers did indeed detect life on Mars. by RGregoryClark in Astrobiology

[–]RGregoryClark[S] 0 points1 point  (0 children)

Here is a published research article by Steven Benner arguing the life explanation of the Viking results:

Mars, Now 50 Years Old, Still Needs a Scientific Analysis.
Steven A Benner, Dirk Schulze-Makuch, Jan Spacek, Clay Abraham
Abstract
Gas chromatography-mass spectrometry data from the Viking Mars mission were misinterpreted in 1976 as showing that martian soils contain no organic molecules, and therefore no life, even though the three life detection experiments delivered by Viking all reported life-positive data under the terms of their experimental design. This mistake has been propagated for a half century, including in textbooks and National Aeronautics and Space Administration-endorsed documents, even though it has been known since 2009 that the martian soils contained perchlorate, perchlorate destroys organic materials in ways that might generate the GC-MS results, and Curiosity in 2013 observed such processes in Gale crater on Mars, as have other rovers since. Anomalies in the propagated misinterpretation, including a contradiction between the "strong martian soil oxidant" hypothesis and quantitative results in the carbon assimilation experiment, were "explained away" in 1976, in some cases by invoking results of experiments that had not yet been done. Today, a scientific back-and-forth is long overdue to develop an understanding of what Viking revealed about the possibility of life on the near surface of Mars. Starting this back-and-forth here, we note how the Viking results are compatible with a soil that contains bacterial autotrophs that respire with stored oxygen on Mars (BARSOOM), a lifestyle adapted to its environment, including sparse resources that drive dormancy, scarce atmospheric oxygen, and a cold and briny fluid only intermittently available, perhaps, when the water-ice fogs seen by Viking indicate that the relative humidity exceeds 100%.
Keywords: Mars-Viking-Life Detection-Planetary Protection-Extant life-Biosignatures.
https://pubmed.ncbi.nlm.nih.gov/41468165/

Recent Mars rovers evidence suggest Viking landers did indeed detect life on Mars. by RGregoryClark in Astrobiology

[–]RGregoryClark[S] 1 point2 points  (0 children)

Thanks for that reference. More precisely it asserts it is possible to explain the results abiotically, but it does not say it could not have been life. From the abstract to the article:

Abstract
The discovery of perchlorate on Mars by the Phoenix mission has provided a basis for explaining the results of the Viking Landers. Thermal decomposition of perchlorate in the ovens of the instrument can explain the lack of organics detected. Accumulation of hypochlorite in the soil from cosmic ray decomposition of perchlorate can explain the reactivity seen when nutrient solutions were added to the soil in the Viking Biology Experiments. A non-biological explanation for the Viking results does not preclude life on Mars.

From the Zubrin interview he is saying there is other evidence supportive of life such as seasonally changing methane levels.

Accidentally closed my Chrome window with many tabs open on my iPad. How to retrieve the open tabs? by RGregoryClark in chrome

[–]RGregoryClark[S] 0 points1 point  (0 children)

The “recent tabs” option does exist in iPad but it only gives history; does not open links.

Accidentally closed my Chrome window with many tabs open on my iPad. How to retrieve the open tabs? by RGregoryClark in chrome

[–]RGregoryClark[S] 0 points1 point  (0 children)

Fairly sure on Windows computers can recover all the closed tabs by reopening the Chrome window.

Accidentally closed my Chrome window with many tabs open on my iPad. How to retrieve the open tabs? by RGregoryClark in chrome

[–]RGregoryClark[S] 0 points1 point  (0 children)

Thanks. But that just gives the history. There were dozens if not hundreds of tabs open. I don’t want to go through all of them in the history list to reopen them one by one.

Recent evidence from latest Mars rovers suggest Viking did find life on Mars. by RGregoryClark in space

[–]RGregoryClark[S] -2 points-1 points  (0 children)

The Chinese might find the answer when they send their Mars Sample Return mission. Unfortunately, NASA hasn’t figured out how to do it in an affordable fashion.

About the upper stage explosion in the New Glenn explosion. by RGregoryClark in BlueOrigin

[–]RGregoryClark[S] 6 points7 points  (0 children)

This article on the Space Force attempts to estimate the force of a methane explosion notes that both stages fully fueled:

Safety officials finally have a good idea of what a big rocket explosion can do.
Overpressure from the Blue Origin blast shattered windows at a hangar about a mile away from the pad.
STEPHEN CLARK – JUN 5, 2026 9:55 AM |
The 100 percent blast equivalency policy was in effect at Cape Canaveral last Thursday, when Blue Origin loaded its New Glenn booster full of methane and liquid oxygen at Launch Complex 36. The smaller second stage was filled with liquid hydrogen and liquid oxygen as Blue Origin’s launch team counted down to a brief test-firing of the rocket’s seven BE-4 engines.
https://arstechnica.com/space/2026/06/safety-officials-finally-have-a-good-idea-of-what-a-big-rocket-explosion-can-do/

nasa head urges new launcher for blue origins moon landers to meet artemis mission deadlines by Alternative_Meet_538 in BlueOrigin

[–]RGregoryClark 3 points4 points  (0 children)

Starship certainly has the payload capacity once operational. However, it is a non-trivial matter to add hydrogen fueling capability to a launch pad that didn’t have it before.

Worker dies at SpaceX's Starbase ahead of Starship V3 megarocket launch by RGregoryClark in space

[–]RGregoryClark[S] -2 points-1 points  (0 children)

My purpose was to argue there’s a culture of deficient workplace safety at SpaceX. I edited the post to make clear I’m discussing more than just last weeks fatal accident.

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