bmears@deltahp.jsc.nasa.gov (Brad Mears) (06/27/91)
In article <37330001@hpindwa.cup.hp.com>, bobj@hpindwa.cup.hp.com (Bob Joslin) writes: |> I've heard that one shuttle launch causes 1/4 of 1% of the ozone to be |> destroyed. This sounds like propaganda to me. That's a lot of ozone, |> even if it is destroyed over a long period of time. I saw the same comments concerning the SRBs effect on the ozone. I have very few hard facts, but I'm happy to share what I have. The following data is from the "Shuttle Flight Operations Manual, Volume 8B - Solid Rocket Booster Systems". This is an official NASA document and is considered authoritative. The SRBs contain a total of approximately 2.3 million lbs of propellant. This total is for two SRBs. The chemical composition of the SRB fuel is broken down below. 14% terpolymer of butadiene, acrylic acid, and an epoxy curing agent (bis-phenol A - epichlorohydrin type) 16% Atomized aluminum powder 70% Ammonium Perchlorate 0.2% Iron Oxide If there are any chemists out there that want to do an analysis of this data, maybe we can get a meaningful opinion on this subject. BTW, SRB burnout occurs at approximately 140,000 feet. Does this count as "high" or "low" in an atmospheric sense? -- Brad Mears bmears@deltahp.jsc.nasa.gov No disclaimer, no quote
pstinson@pbs.org (06/27/91)
In article <37330001@hpindwa.cup.hp.com>, bobj@hpindwa.cup.hp.com (Bob Joslin) writes: > I've heard that one shuttle launch causes 1/4 of 1% of the ozone to be > destroyed. > > Given that NASA is about the only organization capable making an > estimate like this, if this is true, then NASA must have said it. > FALSE. Any organization is capable of making these estimates and not just government agencies or departments. Quite a few statements of this type have come from college campuses around the world. :-)
dil@mace.cc.purdue.edu (Perry G Ramsey) (06/27/91)
In article <1991Jun27.150231.8725@aio.jsc.nasa.gov> bmears@deltahp.jsc.nasa.gov writes: >BTW, SRB burnout occurs >at approximately 140,000 feet. Does this count as "high" or "low" in an >atmospheric sense? This subject has already been beaten to death many times before, with the conclusion that there aren't enough launchings to even begin to compare with other chlorine sources. Just to answer your question, ozone concentration peaks at about 25 km (140,000 ft = 42 km), so yes, at least some fraction of the emission is directly in the ozone. -- Perry G. Ramsey Department of Earth and Atmospheric Sciences dil@mace.cc.purdue.edu Purdue University, West Lafayette, IN USA perryr@purccvm N9LFF
rick@xing (Richard Ottolini) (06/28/91)
In article <37330001@hpindwa.cup.hp.com> bobj@hpindwa.cup.hp.com (Bob Joslin) writes: >I've heard that one shuttle launch causes 1/4 of 1% of the ozone to be >destroyed. This sounds like propaganda to me. That's a lot of ozone, >even if it is destroyed over a long period of time. There must be a certain daily variance in the amount of ozone, but I don't know the number. It is possible this number is within the variance. An analogy that prompts this comment is the ionosphere that varies in size and location during the day. The effect of fuel exhaust on the atmosphere was studied when the American SST program was posulated and canceled in the 1970s. They have some numbers, but atmospheric science has progressed since then.