• 18 Posts
  • 37 Comments
Joined 2 years ago
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Cake day: June 14th, 2023

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  • If you have binoculars you should try using them. It’s not so much about the magnification, but rather the amount of light collected. Basically, the diameter of the objective lens is bigger than your own eyeball lenses/irises, so therefore more light is collected and projected to your retina while using binoculars.

    I’m in western Canada right now and have so far not had the right conditions to see it myself. I’m hoping that might change in the next day or two.



  • Considering the actual post here, plus just decent manners, if you like a book, and you’re able, it’s worth considering supporting the author of said book.

    That being said, you should seriously consider going to your search engine of choice and searching for an archive by a person named Anna: Anna’s Archive if you will. You might find something helpful and interesting.


  • I’m not a geologist but I’ve read up on it a fair bit.

    This Mars photo appears to be sandstone.

    On earth sandstone is usually associated with ancient rivers, lake shores, and sea shores. But also sand dune fields.

    The thing with sandstone though, is it’s not just sand. Rather, it’s sand plus time plus pressure plus cementation.

    Now, the time part is obvious. What’s sandstone now was sand a long ass time ago (usually).

    Pressure? That’s a little harder to understand for me here. Has mars ever had tectonic stuff going on to bury it (and hence have pressure applied), followed by erosion and uplift? Or am I incorrect and pressure is not a necessary condition? Maybe sandstone without pressure is a thing it’s just weaker and/or less dense? Maybe layers of volcanic basalt or something could have a similar effect? I don’t know and would love to have someone more knowledgeable fill this part out.

    Cementation? This part, I’m nearly certain, REQUIRES water. On earth anyway, this happens when ground water absorbs chemicals from other rock/stuff (for example carbonates from sea shells, but there’s lots of other chemicals that can do this), then flows through the beds of buried sand, and some of those chemicals are deposited along with magical chemistry stuff happening, and your sand becomes sand stone.

    So I don’t 100% know that the short answer to your question is “yes”, but I’m leaning towards a solid “yeah, probably, but I’m not a real geologist and Mars isn’t a real Earth so I dunno”.









  • Thanks for providing this update. You added some sources and data that I didn’t know, and your last point clearly articulates the set of likely causes of this misstep.

    When I first became aware of this story my gut-reaction was “I fucking hate unforced errors like this!”; I’m now very curious why this happened the way it did. Mind you, in the grand scheme of things I suspect this is nothing more than a fleeting political blip.










  • I can try to explain, but there are people who know much more about this stuff than I do, so hopefully someone more knowledgeable steps in to check my work.

    What does ‘random’ or ‘noise’ mean? In this context, random means that any given bit of information is equally as likely to be a 1 or a 0. Noise means a collection of information that is either random or unimportant/non-useful.

    So, you say “Compression saves on redundant data”. Well, if we think that through, and consider the definitions I’ve given above, we will reason that ‘random noise’ either doesn’t have redundant information (due to the randomness), or that much of the information is not useful (due to its characteristic as noise).

    I think that’s what the person is describing. Does that help?