Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!samsung!umich!vela!egrunix!awesley From: awesley@egrunix.UUCP (Tony Wesley) Newsgroups: sci.space.shuttle Subject: Re: The shuttle is destroying the ozone layer? Message-ID: <685@egrunix.UUCP> Date: 24 Oct 90 01:44:48 GMT References: <143360@sun.Eng.Sun.COM> <10314.2711c063@pbs.org> <1990Oct10.221645.29969@pmafire.UUCP> <1990Oct19.022310.14985@midway.uchicago.edu> <1990Oct23.030624.7555@cimage.com> Organization: National Federation of Associations Lines: 55 In article <1990Oct23.030624.7555@cimage.com> gregc@dgsi.UUCP (Greg Cronau/10000) writes: >The facts, as I understand them, are: >1.) Clourine (CL) can destroy ozone by combining with it. >2.) CFCs (ClouroFlouroCarbons) can destroy ozone at a *MUCH* greater rate due > to the fact that the mechanism by which CFCs destroy ozone is catalytic. > That is, the CFCs are NOT consumed by the reaction, and a given CFC > molecule can destroy many ozone molecules before it is itself destroyed > by other processes. I believe that a given quantity of CFC has several > orders of magnitude more destructive capacity than the same quanity of CL, > when it comes to the break-down of ozone. This is incorrect. CFCs do not break down ozone. CFCs react with virtually nothing -- their inertness is the major reason they are used. When CFCs reach high altitude, UV can knock the Clorine molecule off the CFC. Clorine is what causes the damage. The Cl reacts with the ozone in a catalytic fashion. The reactions that occur are: Cl + O -> ClO + O 3 2 and ClO + O -> Cl + 2O 3 2 which leaves our Cl atom to go back and do it again. CFC is merely a mechanism to get Cl into the upper atmosphere. I learned much about this from a book by Isaac Asimov, _The Planet That Wasn't_. The chapters "The Smell of Electricity," "Silent Victory," and "Change of Air" deal with the ozone layer and the mechanism by which CFCs reduce it. >3.) The shuttle's SRBs produce Hydroclouric acid (HCL) *NOT* CFCs. See above. This is not relevent. >4.) The writer of the report failed to make any distiction between the HCL > released by the SRBs and the ozone damage caused by CFCs. He treated CFC > and HCL as equally damaging. >In short, in the opinion of most of the people on the net, the report had no >basis in fact. I don't recall this conclusion being reached for the reasons you state. If I recall properly, the reason the shuttle wasn't very dangerous to the ozone layer was because it didn't release that much Cl, and that is primarily because the shuttle doesn't fly very much. >gregc@cimage.com -- And little Sir John with his nut brown bowl Tony Wesley/RPT Software And his brandy in the glass voice: (313) 274-2080 And little Sir John with his nut brown bowl awesley@unix.secs.oakland.edu Proved the strongest man at last... Compu$erve: 72770,2053