GAO offers recommendations on dealing with large constellations.
Large Constellations of Satellites:Mitigating Environmental and Other EffectsGAO-22-105166Published: Sep 29, 2022. Publicly Released: Sep 29, 2022.
"A few thousand satellites is a nuisance, but hundreds of thousands is an existential threat to ground-based astronomy.”
https://www.scientificamerican.com/article/satellite-constellations-are-an-existential-threat-for-astronomy/
"an existential threat to ground-based astronomy.”The exact same words were used for the current constellation, which is now maybe a "nuisance".The larger constellations will fly even lower. The number of satellites viewable from a single grouns station doesn't change.The number of satellites that are lit while the onserver is in darkness actually decreases.And that misleading picture again.. Enough already...
SpaceX wasn't forced. They chose to do mitigations as soon as they discovered there was a major problem. Let's not retconn what happened.
Quote from: meekGee on 11/27/2022 03:15 pm"an existential threat to ground-based astronomy.”The exact same words were used for the current constellation, which is now maybe a "nuisance".The larger constellations will fly even lower. The number of satellites viewable from a single grouns station doesn't change.The number of satellites that are lit while the onserver is in darkness actually decreases.And that misleading picture again.. Enough already...A few thousand satellites were never the most worrying issue, as is evident from the fact impacts were always quoted for at least a few tens of thousands of satellites. You're quoting the "nuisance" qualifier to deliberately misconstrue the very first assessments made when these things started to explode, up until the most recent ones with a better quantification of the issue. Moreover, both SpaceX and astronomers worldwide have been forced to enact mitigation measures, costing an indeterminate amount of money for a partial fix nobody likes, and a relevant slice of the cake for astronomy budgets worldwide in terms of the little mitigation that can be made through new data analysis algorithms in salvageable cases, tightened observation schedules and less man-hours available for actual science. This goes for both visible and radio astronomy, with weights depending on the actual subfield. No "incident" has luckily yet happened, in which an ultrasensitive detector might be inadvertently burned by radio emission at the wrong place in the wrong time, or an unlucky optical flash, which is statistically more likely to happen with time and more constellation sprawl.But we know the tune already. Instead of studying on how this obvious issue can be improved, either directly by creating more logical and sustainable constellations, or indirectly through greater knowledge of what the satellites are like -which by the way should be interesting in its own right for a space enthusiast but, oh right, proprietary- to devise how to minimize their impact, sort of like it's being done so far, if a little less half-assedly... some of you insist on ideologically decrying "regulations" (lol), gloss over a headline and ignore the rest of the article, let alone the studies behind it. Enough already, you only have an argument to make: this is good per se, because I like space exploitation - the rest is secondary.
Since BlueWalker3's launch in September, astronomers have been tracking the satellite, and their alarm was heightened following its antenna deployment last month. According to the International Astronomical Union, post-deployment measurements showed that BlueWalker 3 had an apparent visual magnitude of around 1 at its brightest, which is nearly as bright as Antares and Spica, the 15th and 16th brightest stars in the night sky.
Paper: The BlueWalker 3 Satellite Has FadedQuote from: AbstractObservations of BlueWalker 3 (BW3) beginning on December 8 of this year indicate that its apparent brightness had decreased. We postulate that the orbital beta angle and resultant solar power considerations required an adjustment to the satellite attitude around that time. So, the nominally zenith facing side of the flat-panel shaped spacecraft, which supports the solar array, was tilted toward the Sun. Consequently, the nadir side, which is seen by observers on the ground, was mostly dark. Thus, BW3 has generally appeared faint and on some occasions was not seen at all. The amount of fading was up to 4 magnitudes. Numerical modeling indicates that the amount of tilt was in the range 13° to 16°. This situation indicates the improvement in the appearance of BW3 from the ground that can be achieved with small tilts of the spacecraft. Satellite operators and astronomers can jointly address the adverse impact of bright satellites on celestial observations based on this finding.
Observations of BlueWalker 3 (BW3) beginning on December 8 of this year indicate that its apparent brightness had decreased. We postulate that the orbital beta angle and resultant solar power considerations required an adjustment to the satellite attitude around that time. So, the nominally zenith facing side of the flat-panel shaped spacecraft, which supports the solar array, was tilted toward the Sun. Consequently, the nadir side, which is seen by observers on the ground, was mostly dark. Thus, BW3 has generally appeared faint and on some occasions was not seen at all. The amount of fading was up to 4 magnitudes. Numerical modeling indicates that the amount of tilt was in the range 13° to 16°. This situation indicates the improvement in the appearance of BW3 from the ground that can be achieved with small tilts of the spacecraft. Satellite operators and astronomers can jointly address the adverse impact of bright satellites on celestial observations based on this finding.
Fischer (Debra Fischer from NSF): satellite constellations are an “existential threat” to astronomy without mitigation and cooperation with industry. She cites as an example of such cooperation the recent NSF-SpaceX coordination agreement for Starlink Gen2, a model for others. #AAS241
Hubble Telescope Faces Threat From SpaceX and Other Companies’ SatellitesScientists found that an increasing number of pictures made by the iconic orbital observatory are being disrupted by passing satellites....
QuoteHubble Telescope Faces Threat From SpaceX and Other Companies’ SatellitesScientists found that an increasing number of pictures made by the iconic orbital observatory are being disrupted by passing satellites....https://www-nytimes-com.cdn.ampproject.org/v/s/www.nytimes.com/2023/03/02/science/hubble-spacex-starlink.amp.html?amp_gsa=1&_js_v=a9&usqp=mq331AQIKAGwASCAAgM%3D#amp_tf=From%20%251%24s&aoh=16778420907513&csi=0&referrer=https%3A%2F%2Fwww.google.com&share=https%3A%2F%2Fwww.nytimes.com%2F2023%2F03%2F02%2Fscience%2Fhubble-spacex-starlink.html
Quote from: GWR64 on 03/05/2023 08:40 amQuoteHubble Telescope Faces Threat From SpaceX and Other Companies’ SatellitesScientists found that an increasing number of pictures made by the iconic orbital observatory are being disrupted by passing satellites....https://www-nytimes-com.cdn.ampproject.org/v/s/www.nytimes.com/2023/03/02/science/hubble-spacex-starlink.amp.html?amp_gsa=1&_js_v=a9&usqp=mq331AQIKAGwASCAAgM%3D#amp_tf=From%20%251%24s&aoh=16778420907513&csi=0&referrer=https%3A%2F%2Fwww.google.com&share=https%3A%2F%2Fwww.nytimes.com%2F2023%2F03%2F02%2Fscience%2Fhubble-spacex-starlink.htmlAlternate headline: "Hubble Telescope, descending below other satellites, can now see them more clearly"
An interview with astrophysicist Dr. Jonathan McDowell (@planet4589) from the Harvard-Smithsonian Center for Astrophysics on the concerns about megaconstellations photobombing observations from ground-based telescopes.By Ian Atkinson (@IanPineapple)
