Recent content by danR

The very return of the samples is mooted by SpaceX's own Mars plans. They will almost certainly have complete recon landers and rovers in multiple locations ~2030, in preparation for boots on the ground, a base, and (possibly) their envisioned colony. Nothing will be returned. The whole shebang...

Cold molecular hydrogen is easily ruled out in local galaxies and clusters—and Dark Matter preferred—because CMH is not betrayed by its characteristic absorption spectra. In the case at hand there is little chance to obtain absorption spectra. Given the extreme antiquity, I would like to...

That is kind of the worst 'explanation' of any theoretical attribute I have ever kind of seen in a scientific exposition, or something else. Normally when I see something like that, I'm expecting it is a loose sketch for a more rigorous elaboration. Nothing followed. When a theoretician is...

Photons aren't light at all it is electromagnetic waves in the aether it can be nothing else I realize pretending to look for them pays the bills so carry on like this run-on sentence.

There is no iteration of this series that could possibly be thought to be capable of interstellar travel except in the sense of unmanned/robotic/AI probes. Nobody is going to Alpha Centauri in anything less than a nuclear (fission) -powered spacecraft, which makes it rocketry crime that Nixon...

"...because it doesn't interact with light, which means it is effectively invisible to our eyes. Dark matter also exhibits an apparent lack of interaction with other forces like the electromagnetic force." There's no "also" about it. Light involves that very electromagnetic force.

"Neutrinos are charge-less and nearly mass-less particles that blast through the cosmos at speeds approaching that of light. Oddly enough, because of those parameters, neutrinos barely interact with anything." That would be a reason why photons would barely interact with anything. Which they...

"I'm sorry Dave, I'm afraid I can't do that"

The more common term is "ocean landing". https://www.faa.gov/media/72816 There are two different water landings. The booster won't crash; it's termed a "soft water landing": sea level is treated a proxy for land-surface (and ultimately as a sea-platform surface; for most missions, ultimately...

430 micrograms. A lot of things were left out, including the actual means of measuring the gravitational force itself. It's like the stage was set, the extras brought in, the props placed, the lighting turned on and... where is the main actor? BBC article did the same thing. Perhaps everything...

I don't know how many times and how many ways this misapprehension of entanglement has been displayed in pop-science articles. It's probably the number one reason why the lay public keeps coming up with FTL comms schemes: ' See, Bob changes the spin on his electron from up to down and Alice at...

I think the experts have started out with the idea that they want to see humans on Mars and then argued toward that thesis. By the time even SpaceX' enthusiastic, accelerated, timeline gets exploratory boots on the ground, their own robotic autonomy program will have followed an exponential...

Before humans land on Mars, even more so, and sooner . An uncrewed land-and-return mission won't require the vast safety overhead that humans need.

I've advocated letting SpaceX complete this task ever since hearing of the projected timeline snafu: 1. SX's Mars project must needs entail its own sample analyses for a viable colony, or even a basic preliminary crewed Mars base. 2. Falcon Heavy, and especially Starship (later) could send such...

The 1% 'breakeven' (as of this date) is technical validity enough for me. When, after all the innovation, all the expense, all the brainpower... after half a century, we are two orders of magnitude below true breakeven (without the ghost of a prayer, that that achievement will still have any...