SpaceX just got FCC approval to launch 7,518 satellites • Hacker News Board

Re: SpaceX just got FCC approval to launch 7,518 satellites

#111

Post by stcredzero » Thu, Nov 15, 2018, 8:59 PM UTC

dr_orpheus wrote: post #97

tsuraan wrote: post #95

Earlier quoted context omitted.

I believe you're thinking about their initial application. They've updated it [0] to an altitude of 550km, so atmospheric drag should still de-orbit broken satellites fairly promptly. [0] - " rel="nofollow">https://fcc.report/IBFS/SAT-MOD-20181108-00083>

Thank you, I was thinking about their initial application. Yes, de-orbit times from 550 km are on the order of years to possibly tens of years. The requirement from the FCC is to deorbit your satellite within 25 years after the end of mission. Edit: Their most recent application only moved the Phase 1 satellites in to the lower orbit. In later phases they are still planning on having more than 1000 satellites at the…

Yes, de-orbit times from 550 km are on the order of years to possibly tens of years.

So it wouldn't stop progress for a century, but might it put a damper on things on the same scale as the Great Depression?

Re: SpaceX just got FCC approval to launch 7,518 satellites

#112

Post by toomuchtodo » Thu, Nov 15, 2018, 9:00 PM UTC

Rebelgecko wrote: post #105

thinkcontext wrote: post #78

The fact that SpaceX can piggyback on its own customers' launches to put these in orbit is a significant advantage over competing communication constellations. Depending on the cost of their satellites it might make sense to use launching them as a means of testing the upper limits of reusability of their rockets. IE, they might not want to risk a customer payload on a rocket that has made 10 launches. But if they ar…

I would be surprised if they launch many of the satellites on customer launches. They have some very specific orbits, and are planning on dropping the satellites off in orbits much lower than where they will actually be operating. It would probably be more fuel efficient to drop off a bunch of them in the right inclination all at once, then boost them up into spaced out orbits.

It's possible that they will use reflown Falcon 9s that have exceeded their reuse capability (~10 launches) to deliver these satellites. You're only paying for the propellant, the oxidizer, the second stage, and your fixed operations cost; the rest of the vehicle has been amortized through paying customer flights.

Re: SpaceX just got FCC approval to launch 7,518 satellites

#113

Post by randyrand » Thu, Nov 15, 2018, 9:01 PM UTC

airnomad wrote: post #38

Why do they need approval for this? It's not like Space is owned by anyone?

Political power comes from the barrel of a gun, and SpaceX is well within many country's sights.

e.g. that's the law.

Re: SpaceX just got FCC approval to launch 7,518 satellites

#114

Post by stcredzero » Thu, Nov 15, 2018, 9:01 PM UTC

Rooster61 wrote: post #98

_ph_ wrote: post #96

Earlier quoted context omitted.

SpaceX recently updated their plans to put most satellites between 300 and 400km. That ensures a quick deorbit of the satellites and debris and cuts down the ping times.

Interesting. That does make me feel a bit more secure about the whole thing, but it does raise the question of how much they will need to invest in orbital upkeep/replacement of decayed spacecraft. I can see this getting expensive quick.

There are new technologies like air breathing ion engines and electrodynamic tethers, which have the potential to sustain low orbit satellites for years.

Re: SpaceX just got FCC approval to launch 7,518 satellites

#115

Post by ceejayoz » Thu, Nov 15, 2018, 9:04 PM UTC

zackbloom wrote: post #75

Rooster61 wrote: post #53

This scares me a bit. The idea of having LEO internet is great and all, but the idea of quadrupling the number of functioning satellites, all operating in different orbits but at a similar altitude seems incredibly dangerous to me. The article mentions the movie Gravity, which is a bit unrealistic as it portrays multiple large bodies in orbit all being at about the same altitude (which isn't the case in reality). Tha…

Think how big the Earth is. How hard it would be to find a Xerox machine in the Amazon or the middle of the Atlantic if someone stuck it there. Space is much, much, bigger.

> How hard it would be to find a Xerox machine in the Amazon or the middle of the Atlantic if someone stuck it there.

Part of the problem, though, is that said Xerox machine is traveling at 17,000 miles per hour.

We've already had a collision (https://en.wikipedia.org/wiki/2009_satellite_collision) between two of the ~3-4k satellites in orbit. SpaceX's constellation is planned to be double that number.

That single collision turned two satellites into two thousand high-velocity projectiles, too.

Re: SpaceX just got FCC approval to launch 7,518 satellites

#116

Post by PeterisP » Thu, Nov 15, 2018, 9:04 PM UTC

creeble wrote: post #22

Curious how this will pan out. It's a shocking contrast to be in or near a city and have broadband speeds, and then be just a few dozen miles outside one and have... literally nothing. I just loaned my Iridium phone to a friend who was going to the jungle, and although he was able to make the data connection work, even doing email at 2400 baud(!) proved useless. Inmarsat is faster, but vastly more expensive. Outside…

It depends on what you mean by "email". "Doing email" as in SMTP/POP at 2400 baud is feasible, "doing email" as in accessing a https webmail service is not.

You can communicate effectively over 2400 baud if (and only if) you use protocols and services designed for low bandwidth; luckily we have those protocols built and tested, even if we have mostly abandoned some of them.

Re: SpaceX just got FCC approval to launch 7,518 satellites

#117

Post by gsich » Thu, Nov 15, 2018, 9:05 PM UTC

phkahler wrote: post #46

bargl wrote: post #33

This is such a cool problem. We already have a ton of Geo sat which can do this kind of communication but they are super expensive and have a limited bandwidth. These satellites will actually have a ton of limitations in how much data they can send around and how they'll have to balance out their signals. Geo are easier to point to because, well they don't move. But these are going to be moving and changing all the t…

>> Think about switching your router every 10 minutes. Your cell phone switches towers all the time while you're on the road. My cellphone (republic) switches from WiFi to cellular network mid-call if I'm on it when I leave a building. This is not a new problem.

>My cellphone (republic) switches from WiFi to cellular network mid-call if I'm on it when I leave a building. This is not a new problem.

Networking technology switching is unrelated to a call, which always uses cellular.

Re: SpaceX just got FCC approval to launch 7,518 satellites

#118

Post by notimetorelax » Thu, Nov 15, 2018, 9:05 PM UTC

dv_dt wrote: post #92

zaroth wrote: post #11

Too bad the public markets have given Elon such a lashing with Tesla, because I would love to buy into SpaceX. But then, I’m not the only one; “There is an unlimited amount of funding that the company could probably access globally in private markets," Hilmer said, adding that he has personally met many of "a diverse group" interested in SpaceX. Everywhere I travel around the world, investors of all types — individua…

I read that as there is a lot of money that wants to piggyback on the success of SpaceX instead of fundamentally developing anything via their own investments.

Which is fine, if there’s someone who can create it’s amazing if we can support them.

Re: SpaceX just got FCC approval to launch 7,518 satellites

#119

Post by gsich » Thu, Nov 15, 2018, 9:05 PM UTC

bargl wrote: post #33

This is such a cool problem. We already have a ton of Geo sat which can do this kind of communication but they are super expensive and have a limited bandwidth. These satellites will actually have a ton of limitations in how much data they can send around and how they'll have to balance out their signals. Geo are easier to point to because, well they don't move. But these are going to be moving and changing all the t…

>We already have a ton of Geo sat which can do this kind of communication but they are super expensive and have a limited bandwidth.

And high delay, which is the main problem.

Re: SpaceX just got FCC approval to launch 7,518 satellites

#120

Post by IshKebab » Thu, Nov 15, 2018, 9:09 PM UTC

dv_dt wrote: post #92

zaroth wrote: post #11

Too bad the public markets have given Elon such a lashing with Tesla, because I would love to buy into SpaceX. But then, I’m not the only one; “There is an unlimited amount of funding that the company could probably access globally in private markets," Hilmer said, adding that he has personally met many of "a diverse group" interested in SpaceX. Everywhere I travel around the world, investors of all types — individua…

I read that as there is a lot of money that wants to piggyback on the success of SpaceX instead of fundamentally developing anything via their own investments.

What do you think investment is exactly?