ultimately even if the court found against the FCC it would only mean that the blanket waiver that the FCC uses could just be codified into law. I'd guess that there's enough influence from aerospace companies that they could get something passed that says that NEPA doesn't apply to space.
Quote from: RoboGoofers on 01/17/2020 08:48 pmultimately even if the court found against the FCC it would only mean that the blanket waiver that the FCC uses could just be codified into law. I'd guess that there's enough influence from aerospace companies that they could get something passed that says that NEPA doesn't apply to space.NEPA doesn't do space. They are busy with environment="biosphere". And the current status quo will continue unless scientists will make a reasonable argument that the light dots patterns in the skies can anyhow influence life on earth. Which is unlikely.
The slides to the talk a few posts above can be found here: https://planet4589.org/space/misc/Seitzer.pdfThese are the most interesting to me, because their effects are the ones most misrepresented in popular media. Starlink flies so low that a few satellites are over any given point and a tiny fraction is actually visible, the rest hides in the shadow. He also did an estimation at the OneWeb height which allows for so much more illumination that you don't get any satellite-free sky during some nights.
"Astronomy Confronts Satellite Constellations" Press Conference from AAS 235, Honolulu, Hawai‘i, 4-8 January 2020:
Quote from: niwax on 01/17/2020 08:15 amThe slides to the talk a few posts above can be found here: https://planet4589.org/space/misc/Seitzer.pdfThese are the most interesting to me, because their effects are the ones most misrepresented in popular media. Starlink flies so low that a few satellites are over any given point and a tiny fraction is actually visible, the rest hides in the shadow. He also did an estimation at the OneWeb height which allows for so much more illumination that you don't get any satellite-free sky during some nights.That's an interesting slide deck. And it shows on slide 23 that, from CTIO at least, the low-altitude "trains" of deploying Starlinks aren't illuminated at all past an hour after astronomical twilight. Even in the middle of summer, which is the worst-case illumination.
Anyway, after listening to that talk, I personally strongly feel megaconstellations really should be required to operate in much lower orbits (closer to 550km if not lower), considering astronomical and orbital debris concerns. Obviously brightness still needs to be limited. I'm pretty concerned about the OneWeb constellation that's starting to launch as well in a few weeks, and really hoping Starlink doesn't actually need the higher orbital shells, as satellites in those orbits are likely to interfere with measurements the entire night.
Why not make the sats bigger? I don't see the point of having 10ks of sats.
Quote from: Oli on 01/21/2020 11:02 amWhy not make the sats bigger? I don't see the point of having 10ks of sats.The number of sats required is determined by the required coverage from that orbital altitude. Making them bigger serves no purpose whatsoever.
We explore the potential impacts to, and degradations of, Space Situational Awareness (SSA) and related operations that may be caused by New Space large constellations. In this paper, the initial Starlink constellation layer (anticipated completion in 2025) is adopted as a sample case study to explore these potential SSA impacts and degradations. Results indicate that for normal SSA observations and tracking purposes, SSA degradations may be minimal at least for systems with relatively short integration times. Impacts may be further mitigated if accurate large constellation positional information incorporating planned maneuvers are utilized in the optical tracking operations procedures to effectively mask out the large constellation spacecraft. However, there are potential operational risks to imaging by optical systems with very wide fields of view, lower spatial resolution, long integration times (especially systems with large apertures), and when imaging very faint objects. SSA system throughput, efficiency and accuracy may be degraded as well.
At today’s Astronomy and Astrophysics Advisory Committee meeting, Pat McCarthy of the NSF’s OIR Astronomy Lab said Elon Musk participated in a call in December saying he was “personally committed” to minimizing the impact of Starlink on astronomy.
This article aims to highlight the impact for ground based astronomical observations in different windows of the electromagnetic spectrum coming from the deployment of fleets of telecommunications satellites. A particular attention is given to the problem of crowding of circumterrestrial space by medium/small size orbiting objects. Depending on their altitude and surface reflectivity, their contribution to the sky brightness is not negligible for professional ground based observations. With the huge amount of about 50,000 new artificial satellites for telecommunications planned to be launched in Medium and Low Earth Orbit, the mean density of artificial objects will be of >1 satellite for square sky degree; this will inevitably harm professional astronomical images. Only one of these project, Starlink@SpaceX's, was authorized by US Federal Communication Commission, F.C.C. and plans to deploy about 42,000 not geostationary satellites, which will shine from the 3rd to the 7th magnitude in sky after sunset and before sun dawn. All satellites will leave several dangerous trails in astronomic images and will be particularly negative for scientific large area images used to search for Near Earth Objects, predicting and, eventually, avoiding possible impact events. Serious concerns are common also to other wavelengths eligible for ground based investigation, in particular for radio-astronomy, whose detectors are already saturated by the ubiquitous irradiation of satellites communication from Space stations as well as from the ground.Understanding the risk for astronomical community, a set of actions are proposed in this paper to mitigate and contain the most dangerous effects arising from such changes in the population of small satellites. A dedicate strategy for urgent intervention to safeguard and protect each astronomical band observable from the ground is outlined.
Astronomers Appealhttps://astronomersappeal.wordpress.com/
Thus with 50k satellites the “normality” will be a sky crowded with artificial objects (every one square degree of the sky will have a satellite crawling in it along the whole observing night).
Quote Trimmed
Quote from: pochimax on 01/30/2020 02:05 pmAstronomers Appealhttps://astronomersappeal.wordpress.com/Who wrote this crap, same error as was pointed above, how could astronomers make fundamental errors like this:QuoteThus with 50k satellites the “normality” will be a sky crowded with artificial objects (every one square degree of the sky will have a satellite crawling in it along the whole observing night).I think this has officially went into the luddite territory, the whole thing is filled with lies and errors.
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Who can sign?1) professional Astronomers,2) Technologists/ENGINEERS,3) PHD Students,4) Collaborators and/or AssociateS AT International Scientific Institutes
