Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

SpaceX punched a hole in the ionosphere

spaceweatherarchive.com

Post reply on HN
Print view View original

61–70 of 231 posts

Re: SpaceX punched a hole in the ionosphere

#61

Post by rdlw »

idlewords wrote: post #51
panick21_ wrote: post #9

Earlier quoted context omitted.

The waste, waste majority of sats never turn into space debris. Every single sat that launches today in the West has a deorbit planned. The only sat that turn into space debris will be those that brake unexpectitly and totally unrecoverable. And the Starlink sats are so low that they dont really turn very meaningful debris ever. And in general, yes LEO can handle millions of sats. We have like 150k cars in a single t…

Except that all distinct orbits at the same altitude eventually collide.

What do you mean? If they're both circular orbits, they'll have the same period, so they'll never collide—they'll always be on opposite sides of the Earth. In fact, this goes for any two orbits with identical periods.

Re: SpaceX punched a hole in the ionosphere

#65

Post by [deleted] »

jrockway wrote: post #36
dfox wrote: post #25

Earlier quoted context omitted.

That is completely different definition of HF. And if they use radio (lower latency than fiber, in theory and in right circumstances ), it is somewhere between SHF and EHF (C through V in the IEEE nomenclature), ie. what sane person would informally call “microwave”, not HF.

There was a thread on here the other day about HF traders using HF radio.

[deleted]

Re: SpaceX punched a hole in the ionosphere

#67

Post by cj »

pseg134 wrote: post #55
esquivalience wrote: post #5

Seems like this isn't considered to be a big issue, beyond that it is a very visible thing that instinctively 'feels' like a bad idea. > Rocket engines spray water (H2O) and carbon dioxide (CO2) into the ionosphere, quenching local ionization by as much as 70%. A complicated series of charge exchange reactions between oxygen ions (O+) and molecules from the rocket exhaust produce photons at a wavelength of 6300 Å–the…

It may not seem like a big issue but it speaks to the attitude of billionaires. I am no longer free to vent personal amounts of coolant from a refrigerator but Elon Musk can punch all of the holes he wants with his expensive rockets.

I wonder what the total carbon footprint is of the Musk Empire. (Tesla + SpaceX + X + Boring Company + …)

Re: SpaceX punched a hole in the ionosphere

#68

Post by katbyte »

pseg134 wrote: post #55
esquivalience wrote: post #5

Seems like this isn't considered to be a big issue, beyond that it is a very visible thing that instinctively 'feels' like a bad idea. > Rocket engines spray water (H2O) and carbon dioxide (CO2) into the ionosphere, quenching local ionization by as much as 70%. A complicated series of charge exchange reactions between oxygen ions (O+) and molecules from the rocket exhaust produce photons at a wavelength of 6300 Å–the…

It may not seem like a big issue but it speaks to the attitude of billionaires. I am no longer free to vent personal amounts of coolant from a refrigerator but Elon Musk can punch all of the holes he wants with his expensive rockets.

Venting refrigerant does actual measurable damage that takes decades to repair, this does not (that we k ow of) and is undone in a single day

I get what and agree with what your trying to say but a better comparison is needed

Re: SpaceX punched a hole in the ionosphere

#69

Post by dfox »

tomjakubowski wrote: post #38
jrockway wrote: post #36

Earlier quoted context omitted.

There was a thread on here the other day about HF traders using HF radio.

Yes that's right, also known as shortwave radio. https://spectrum.ieee.org/amp/wall-street-tries-shortwave-ra...

Well, the article itself does a pretty good job of describing why it is not an exactly good idea. What it does not say (and what probably nobody suggesting that ever though about) is that the sky-wave propagation mode is either about reflection off the ionosphere or refraction effects of the ionosphere, both of which means that the propagation path is significantly longer and in the refraction case over “slower” medium. The resulting latencies are almost certainly large enough that the whole thing does not make sense even before thinking about the bandwidth and frame sizes.

Re: SpaceX punched a hole in the ionosphere

#70

Post by TaylorAlexander »

Jeff_Brown wrote: post #35
arbuge wrote: post #23

Earlier quoted context omitted.

> One famous example occured on August 25, 2017, when a Falcon 9 rocket carrying Taiwan’s FORMOSAT-5 satellite created a hole four times bigger than the state of California. Doesn't sound too local to me.

Good point. Deserves some numbers. California's area is about 500 thousand km^2, and the Earth's is about 500 million, which means the side facing the Sun is about 250 million, so we're talking about 0.2% of the area facing the sun. Suppose the hole takes six hours to heal (the article makes it sound like it takes much less), and suppose there's a launch every month (since launches have in the past carried 600 satell…

Another way of putting it is that it could potentially affect 40 million people.
Post reply on HN