Here's a novel idea for a fix: admit that Starlink is flawed, shut down the project, and come up with another way to make money.
SpaceX working on fix for Starlink satellites so they don’t disrupt astronomy
191–200 of 276 posts
Re: SpaceX working on fix for Starlink satellites so they don’t disrupt astronomy
#192Earlier quoted context omitted.
The ground system is what will make or break starlink. Every phased array antenna to date is at a price point that would put starlink selling exclusively to enterprise customers. This means consumers won't be able to get it unless you're in the 1% and living very remote. SpaceX will not realize 20Gbps per satellite in useable bandwidth. It's more like 5Gbps. http://www.mit.edu/~portillo/files/Comparison-LEO-IAC-2018-…
OneWeb claims to have cracked that, for a price point of $200-300. https://spacenews.com/wyler-claims-breakthrough-in-low-cost-... Even if it winds up being more expensive, you might see a neighborhood getting an antenna and distributing it to a group of houses. > SpaceX will not realize 20Gbps per satellite in useable bandwidth. It's more like 5Gbps. Based on guesses made prior to the first launch of production hard…
These are not guesses. These are calculations based on FCC filings with things like EIRP, PFD, etc, all included. SpaceX cannot simply transmit hotter than they filed for just because the filing is old.
If anything, they're worse than those calculations since there's no ISL, and there were reported propulsion system problems.
I personally can't see a neighborhood going in on satellite internet since they still need to transmit between each other, which would mean more equipment.
Re: SpaceX working on fix for Starlink satellites so they don’t disrupt astronomy
#193Earlier quoted context omitted.
That's a good point. SpaceX could be the key to launching a horde of new Hubbles. However that's not so likely in the short run because everything is going towards the JWST.
JWST is a great project and a type of project we should strive for. I'm personally just annoyed why the conversation is so defensive and negative. I don't know much about astronomy, but from what I understand the Earth's atmosphere is hard to deal with, why aren't we talking more about what can be done with this new tech, and not how it makes current things more difficult
I'm personally just annoyed that people are so happy to be annoyed at each other every time this discussion comes up, so there's that.
Astronomers have been talking and acting for decades to take advantage of new technologies like orbital observatories.
Re: SpaceX working on fix for Starlink satellites so they don’t disrupt astronomy
#194Earlier quoted context omitted.
Earth's atmosphere is annoying, yes, but for huge swathes of observational science it's not a deal-breaker. Not having massive telescopes on the ground where you can fiddle with your instrumentation and take advantage of apertures and construction techniques simply not possible in space _is_ a deal-breaker. The required precision for construction of telescopes is incredible, and doesn't translate to space well, espec…
I live in a very large city in Europe. I think the number of stars you can see is less than 20. Ground based pollution is horrible, I don't know how you can compare those two.
If you go back 100 years, you could see stars great from the middle of your very large city in Europe. Then the lights came, one by one.
This process is just starting with satellites. Can you see the connection now?
Re: SpaceX working on fix for Starlink satellites so they don’t disrupt astronomy
#195Earlier quoted context omitted.
Yes, it might be that the astronomer community didn't expect Starlink to actually happen. A lot of people still haven't learned that SpaceX isn't just hyping things up.
Off topic: I mentioned to someone at StarLink the idea of equipping their gear to perform global RF interferometry, will let you know if it turns into something!
That's not a new idea, and it's a lot harder than it looks.
It would be awesome if Starlink would donate bandwidth for the Greenland and South Pole EHT telescopes. Right now there's no "first look" capability for them.
Re: SpaceX working on fix for Starlink satellites so they don’t disrupt astronomy
#196Earlier quoted context omitted.
But in that case you have to travel to a remote location (most likely using a car or plane ironically). Hence, is it so far fetched that if you want to explore space in future you will do it from a different vantage point? Like via a satellite, or maybe in 50 years you go to a space station or the moon directly to do so. With tech it has always been this way- it's nothing new.
The costs are orders of magnitudes more than simply travelling to study nature where it is and will continue to be hugely expensive for a long long time.
I'm sure people said that about cars, trains and the steam engine also.
Re: SpaceX working on fix for Starlink satellites so they don’t disrupt astronomy
#197Re: SpaceX working on fix for Starlink satellites so they don’t disrupt astronomy
#198(I'm not speaking for any of my current or past employers, just for myself, and how I've seen this play out. One employer being a telescope impacted by Starlink, and the other being SpaceX, I want both sides to succeed.) First, astronomers know that satellites can disrupt observations. They've known for a while, and have had to deal with things like flares from Irridium satellites, which were probably when these prob…
As an expert would you be able to comment on my speculation:
It seems like this whole hullabaloo is because a SpaceX launch happened to coincide with a rare event at an inopportune time:. The alpha monocerotids have a narrow band with a long recurrence time (2h window, with a peak recurrence on the order of 10 years). Moreover, some monocerotid observers are in parts of the world where they will appear near Dawn or dusk, so yes some of the starlinks will flash (as you mentioned). In general, the SpaceX launches will only cluster in that fashion a few days after launch as they haven't disperesed into final formation yet. Any other time this wouldn't be a problem.
Re: SpaceX working on fix for Starlink satellites so they don’t disrupt astronomy
#199Earlier quoted context omitted.
It wasn't a "radio license." It was an authorization to "construct, deploy, and operate a proposed non-geostationary orbit (NGSO) satellite system comprising 4,425 satellites for the provision of fixed-satellite service (FSS) around the world." I don't see why the FCC wouldn't consider impact to visual astronomy, when they did consider increased collision risk (also unrelated to any regulated frequencies). > IAU publ…
> It wasn't a "radio license." It's fundamentally a radio license: https://www.law.cornell.edu/cfr/text/47/25.114 > when they did consider increased collision risk Yup, they are supposed to evaluate orbital debris and collision risk, too, 47 CFR 25.114(d)(14). That, and equitable service (for some services) to Alaska/Hawaii are the only non-radio concerns they are permitted by regulation to consider.
> they are permitted by regulation
Where is the restriction to only those concerns? 47 CFR § 25.156 has some pretty vague language about "the public interest, convenience and necessity."
Thanks for pointing out that the FCC is required to evaluate orbital debris and collision risk, but I don't think the FCC is prohibited from considering other concerns (and i might be wrong on that).
Re: SpaceX working on fix for Starlink satellites so they don’t disrupt astronomy
#200Earlier quoted context omitted.
yep. the referenced articles are from this summer. still before the launches
60 satellites were launched on 24 may 2019. It looks like all the articles are after that, in response to people seeing the satellites in the sky.
Here's a 1999 article, well before the announcement of Starlink, talking about the increasing problems of trails spoiling deep sky observations--- https://www.sciencedirect.com/science/article/pii/S027311779...
> From Table 1 it is clear that since 1985 the annual mean number of trails has risen from 2.5 to 2.9 in a 60 minute exposure, an increase of 16%; the number of spacecraft on orbit has increased by 39% in the same period. Since the trail rate data comes from a set of plates not selected for time of night of exposure, the trail rate is averaged over an entire night. Since trailing is most frequent in the two hours after sunset and before sunrise, it would be expected that the trail rate would not increase as rapidly as the spacecraft population. However, the trend is such that it supports the view that plate trailing is caused by spacecraft and large debris and not by debris more generally. The figures suggest that the satellite population is doubling approximately every 14 years at present launch rates. The concern of the astronomical community is that due to the advent of large satellite constellations such as IRIDIUM and, further in the future, a TELEDESIC network, there will be a sudden increase in the numbers of satellites capable of causing trailing. The time available to find a solution is thereby reduced.
It even foresees SpaceX's "solution" that they are trialing:
> The Space Agencies could also assist by reducing satellite albedos.
It's also discussed in similar terms in "Adverse Environmental Effects on Astronomy", D. McNally, 1992.
You can find early 2000's complaints about Iridium-spoiled optical observations.
You can find late 1960's papers analyzing the impact of satellites on optical astronomy... that point to exactly where we are now.
It's hardly a "surprise to the optical astronomy community." If there's any surprise, it's that people are actually willing to listen to their concerns.