I was thinking more about elements such as cobalt and chrome which are not commonly airborne
Quote from: Jim on 01/14/2022 01:44 pmI was thinking more about elements such as cobalt and chrome which are not commonly airborneHuh. I sort of doubt there’s much of those elements in Starlink as they’re kind of expensive,
This is a relevant article, it looks like it's mainly an Aerospace Corp team studying this: Aerospace Corp. raises questions about pollutants produced during satellite and rocket reentryMartin Ross talked about this in a Space Show episode: https://thespaceshow.com/show/08-jun-2021/broadcast-3702-dr.-martin-ross
Quote from: su27k on 01/16/2022 12:38 pmThis is a relevant article, it looks like it's mainly an Aerospace Corp team studying this: Aerospace Corp. raises questions about pollutants produced during satellite and rocket reentryMartin Ross talked about this in a Space Show episode: https://thespaceshow.com/show/08-jun-2021/broadcast-3702-dr.-martin-rossI was hoping to see some actual information in that SpaceNews article, but it did at least lead me to this paper (abstract)...https://ui.adsabs.harvard.edu/abs/2020AGUFMGC0420004H/abstractDoes anyone have access to the paper itself?
it is strange that everyone forgot about the F9 second stage, which weighs 4 tons, that is, like 15 satellites
Quote from: vsatman on 01/16/2022 04:48 pmit is strange that everyone forgot about the F9 second stage, which weighs 4 tons, that is, like 15 satellitesSecond stages are not relevant because all lunch vehicles burn them up in the atmosphere. Only SpaceX specific concerns shall be raised.
In the latest response to Viasat, SpaceX quoted 3 studies to show satellite reentry has negligible effect on the environment:QuoteSimilarly, two independent studies that the European Space Agency (“ESA”) commissioned in 2019—the ATISPADE and ARA studies—show that satellite reentry has a “negligible” effect on the environment.18The ATISPADE study looked at the effect of reentering satellites on the ozone layer. It found that, in the worst case analyzed, the additional yearly ozone reduction was “negligible when compared to the impact of anthropogenic activities,” only between 0.0006% and 0.0008% of global annual ozone loss.19 While the worst case used in the study assumed an average of 450 tons worth of satellites reentering every year and a peak of 650 tons per year,20 the fundamental conclusion—that the impact to the ozone is “negligible” compared to other sources—remains valid even when extrapolating to one order of magnitude more mass per year, as Viasat aggressively assumes would occur.21But Viasat presents no justification for its allegations that these extremely aggressive scenarios will come to pass. Indeed, one leading study raises questions about Viasat’s fundamental premise, finding that the chemical reactions that take place during meteorite reentry do not create alumina at all, even though meteorites contain aluminum.22 In fact, no alumina has ever been detected using rocket-borne spectrometry specifically looking for all aluminum species precipitated by reentering meteorites.The ESA-commissioned ARA study undercuts Viasat’s overblown claims—parroted by NRDC/IDA and others—about the climate effects of the Gen2 satellites. The study found the climate effects of satellite reentry to be minute compared to other man-made sources. For instance, in the worst-case scenario, the annual impact of satellite reentry was 290,000 times less than the annual impact of the aviation sector and 650,000 times less than the annual impact of the road transportation sector.23 Again, even when extrapolated to an order of magnitude greater than the worst case evaluated in the ARA study, the effect would remain negligible relative to other man-made sources. Similarly, assuming the extremely aggressive reentry figures that Viasat touts, the annual impact of reentering Gen2 satellites on Earth’s albedo—the fraction of solar radiation that is reflected away from Earth—will be negligible compared to natural sources (i.e., just 0.005% of the amount of mineral dust created annually through naturally occurring dust storms from the Sahara Desert alone).24FCC filing: https://licensing.fcc.gov/myibfs/download.do?attachment_key=17743215Reference #22 is the paper Meteor-Ablated Aluminum in the Mesosphere-Lower Thermosphere
Similarly, two independent studies that the European Space Agency (“ESA”) commissioned in 2019—the ATISPADE and ARA studies—show that satellite reentry has a “negligible” effect on the environment.18The ATISPADE study looked at the effect of reentering satellites on the ozone layer. It found that, in the worst case analyzed, the additional yearly ozone reduction was “negligible when compared to the impact of anthropogenic activities,” only between 0.0006% and 0.0008% of global annual ozone loss.19 While the worst case used in the study assumed an average of 450 tons worth of satellites reentering every year and a peak of 650 tons per year,20 the fundamental conclusion—that the impact to the ozone is “negligible” compared to other sources—remains valid even when extrapolating to one order of magnitude more mass per year, as Viasat aggressively assumes would occur.21But Viasat presents no justification for its allegations that these extremely aggressive scenarios will come to pass. Indeed, one leading study raises questions about Viasat’s fundamental premise, finding that the chemical reactions that take place during meteorite reentry do not create alumina at all, even though meteorites contain aluminum.22 In fact, no alumina has ever been detected using rocket-borne spectrometry specifically looking for all aluminum species precipitated by reentering meteorites.The ESA-commissioned ARA study undercuts Viasat’s overblown claims—parroted by NRDC/IDA and others—about the climate effects of the Gen2 satellites. The study found the climate effects of satellite reentry to be minute compared to other man-made sources. For instance, in the worst-case scenario, the annual impact of satellite reentry was 290,000 times less than the annual impact of the aviation sector and 650,000 times less than the annual impact of the road transportation sector.23 Again, even when extrapolated to an order of magnitude greater than the worst case evaluated in the ARA study, the effect would remain negligible relative to other man-made sources. Similarly, assuming the extremely aggressive reentry figures that Viasat touts, the annual impact of reentering Gen2 satellites on Earth’s albedo—the fraction of solar radiation that is reflected away from Earth—will be negligible compared to natural sources (i.e., just 0.005% of the amount of mineral dust created annually through naturally occurring dust storms from the Sahara Desert alone).24
Space hardware tumbling out of orbit may lead to unforeseen environmental and climate impacts. Due to the growing scale and pace of launch activities, what is needed is better monitoring of the situation, as well as regulation to create an environmentally sustainable space industry.Making that case is Jamie Shutler, associate professor of Earth observation at the University of Exeter, Cornwall.Shutler and colleagues authored the research paper “Atmospheric impacts of the space industry require oversight” in the August issue of the journal Nature Geoscience.