• maegul (he/they)@lemmy.ml
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    1 year ago

    It feels like we’re approaching a situation where good clean astronomical data is going to have to be collected off-world.

    Like, people in astronomy must be talking about such a scenario and how far away it is and what needs to be done.

    A moon base seems like an obvious solution with dishes and telescopes all over the place.

    • maëlys@lemm.eeOP
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      1 year ago

      well polluting earth orbit with parasite radio frequencies is in SpaceX business model favor: that way the scientific communtiy well be obliged to have observatories beyond starlink orbit (ie Leo i think), so u would have to create ur cluster of radio astronomy satellites and would have to contract SpaceX to deliver them for you to the intended orbit…just a guess but one would think this way, since every company is profit driven after all.

  • WagnasT@iusearchlinux.fyi
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    1 year ago

    https://www.aanda.org/component/article?access=doi&doi=10.1051/0004-6361/202346374 Here is the paper, it has free access which is nice. Most of this went over my head but the conclusions are well written. Basically they were able to detect broadband and narrow band emissions from the satellites as they passed by that were outside of their assigned range. Some of the frequencies they attributed (or at least speculated) to ground based transmissions reflected off them and they are asking regulators to consider these reflected emissions in addition to EMI coming from the craft itself. Cool stuff, but my favorite part is that they think there is a 25MHz oscillator on them because they detected a harmonic series with 25MHz as the base. Are you serious??!? how cool is that? 25MHz isn’t even in the range they were scanning and they figured it out anyway. So from earth, they were able to detect the faintest signal from some onboard microcontroller just doing its job, not even being a radio device, just ticking away at its designed clock speed. I use arch linux btw.

    • mackwinston@feddit.uk
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      1 year ago

      Oscillators for computers are quite easy to detect because they create an enormous series of harmonics, and relatively strong ones. This is because a typical oscillator for this application is square wave, and an ideal square wave is the sum of sine waves starting at the fundamental frequency, with each 3rd harmonic 1/3rd of the power as the previous (so if you have a 25MHz oscillator, you’ll have the fundamental frequency of 25MHz at amplitude 1, 75MHz at amplitude 0.33, 125MHz at amplitude 0.11 and so on ad infinitum). Eventually you may end up with a PCB trace or wire that just accidentally happens to be the right length to be resonant, and that harmonic will radiate quite strongly.

      When your intended signal is minuscule, it doesn’t take much to have it swamped by some unintentional radiator - at the very least it’s extra noise you need to deal with.

      A good example of unintentional radiators swamping a signal, a problem with some aircraft VHF com radios when receiving is that something like the 11th harmonic of the local oscillator (used to tune the radio) on certain VHF channels will completely swamp the GPS L1 band as it leaks out the VHF radio. The signal strength of this harmonic is absolutely minuscule, but it’s huge compared to the GPS L1 signal, and it’s the LO in the receiver rather than a spurious emission from the transmitter (part of the procedure of fitting a new VHF radio to an aircraft is making sure it doesn’t interfere with a GPS receiver, and if it does, a stub filter usually needs to be fitted to the antenna port of the radio).

  • PoisonedPrisonPanda@discuss.tchncs.de
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    1 year ago

    we can literally observe how dumb humanity is to let the orbit become the next earths trashcan.

    after polluting the land, air and ocean was not enough.

    edit: I am aware thats off topic hkwever every time J read about starlink it makes me sad.

  • I_Miss_Daniel@kbin.social
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    1 year ago

    I would ask people to consider the benefits to the globe of having ubiquitous 100+ Mbps internet no matter where you are.

    Most of the people, myself included, who get Starlink get it because there’s no other viable option - usually due to distance from towns and cities.

    Certainly there is some pollution as a result of building and sending the 2,000+ satellites, but it may be a net positive compared to the environmental impact of digging a trench to each property, manufacturing and laying a fibre optic cable to the end user.

    The end user routers use about 30 watts which is also a higher cost compared to the 5 watts or so most other technologies use. Mine runs on solar.

    I’m not happy about giving Elon money for this service of course given his behaviour - he’s not the majority owner at least.

    The unintended interference is probably something that can be designed away to some degree - I’m guessing harmonics from the beam forming are tricky if that’s the cause.

    • maëlys@lemm.eeOP
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      1 year ago

      well african people get accessible internet, at the expense of scientific research. which one would be more relevant to humanity? one might ask…

      • Dojan@lemmy.world
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        1 year ago

        But how much of the internet in Africa is actually served by Starlink?

        Africa is a massive continent with a wealth of countries with varying demographics, it’s no wonder that they have a 40% internet penetration rate compared to the world average 60%.

        I don’t think Starlink is going to change that.

      • NuPNuA@lemm.ee
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        1 year ago

        It’s not just developing nations, even developed nations have areas people live that aren’t viable to run fibre connections to.

  • 133arc585@lemmy.ml
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    1 year ago

    Capitalism sure is efficient at exploiting externalities. SpaceX gets to ignore the difficulty and cost of stopping radiation pollution. The cost gets externalised to research institutions, academic researchers, government agencies (and so indirectly the taxpayer), and other corporations. Whereas it might cost $X for SpaceX to not cause the problem in the first place, it might cost $10X or $50X or more when everyone else has to duplicate cost and effort to overcome SpaceX’s pollution.