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I am not sure. Why are you mentioning flights? I am talking about this [1] and [2]. It does not have anything to do with regular planes.. [1] https://arstechn

I am not sure. Why are you mentioning flights? I am talking about this [1] and [2]. It does not have anything to do with regular planes.. [1] https://arstechnica.com/science/2018/03/spacex-launch-last-year-punched-huge-temporary-hole-in-the-ionosphere/ https://arstechnica.com/science/2018/03/spacex-launch-last-y... [2] https://www.engadget.com/2018/03/25/spacex-rocket-carved-giant-hole-in-ionosphere/ https://www.engadget.com/2018/03/25/spacex-rocket-carved-gia...

Arnt 8y ago
He's trying to say that rockets emit CO₂, but there are very few of them compared to other things that also emit CO₂ at high altitudes, namely airplanes. He's also saying that some rockets have significant other pollution problems, but not SpaceX's.
- Robotbeat 8y ago
  Indeed. And there may come a time when such emissions are enough to matter, but we should then just apply a proper tax to them (as well as airplanes). That’d encourage using alternatives (like hydrogen which is actually a superior rocket fuel from an exhaust velocity perspective but is harder to handle and leads to greater dry mass) and also provide incentive to pull such emissions from the atmosphere. Elon Musk has advocated such a broad carbon tax, including on SpaceX’s rockets (which use kerosene and eventually methane).
Robotbeat 8y ago
There’s no evidence that the impact on the extremely low density part of the atmosphere makes any kind of environmental problem except perhaps for sensitive radio wave measurements (ie GPS, whose satellites are also launched on rockets).
- buvanshak 8y ago
  >There’s no evidence that the impact on the extremely low density part of the atmosphere makes any kind of environmental problem That is what people thought about automobiles emitting co2. If we have learned anything, we would be extremely wary of anything that causes big disruptions in the environments, how ever innocent it might seem...
  - Robotbeat 8y ago
    That’s not true. We knew about the warming effect of CO2 since 1897 or earlier and over 100 years ago, we knew that continual burning of coal and other fossil fuels would cause considerable warming.
    - buvanshak 8y ago
      >we knew that continual burning of coal and other fossil fuels would cause considerable warming. Wrong. We didn't know that. We hoped the co2 will be cleaned up by the mechanisms already in place, and we thought the effect would only be temporary. Just like we think the holes caused by the rockets are temporary now, and will not have any cascading effects. Incredibly short sighted and We have learned nothing from history if we continue to reason like this.
      - Robotbeat 8y ago
        Yeah, we did know: https://dotearth.blogs.nytimes.com/2016/10/21/coals-link-to-global-warming-explained-in-1912/ https://dotearth.blogs.nytimes.com/2016/10/21/coals-link-to-...

Arnt 8y ago

He's trying to say that rockets emit CO₂, but there are very few of them compared to other things that also emit CO₂ at high altitudes, namely airplanes. He's also saying that some rockets have significant other pollution problems, but not SpaceX's.

Robotbeat 8y ago
Indeed. And there may come a time when such emissions are enough to matter, but we should then just apply a proper tax to them (as well as airplanes). That’d encourage using alternatives (like hydrogen which is actually a superior rocket fuel from an exhaust velocity perspective but is harder to handle and leads to greater dry mass) and also provide incentive to pull such emissions from the atmosphere. Elon Musk has advocated such a broad carbon tax, including on SpaceX’s rockets (which use kerosene and eventually methane).

Robotbeat 8y ago

There’s no evidence that the impact on the extremely low density part of the atmosphere makes any kind of environmental problem except perhaps for sensitive radio wave measurements (ie GPS, whose satellites are also launched on rockets).

buvanshak 8y ago
>There’s no evidence that the impact on the extremely low density part of the atmosphere makes any kind of environmental problem That is what people thought about automobiles emitting co2. If we have learned anything, we would be extremely wary of anything that causes big disruptions in the environments, how ever innocent it might seem...
- Robotbeat 8y ago
  That’s not true. We knew about the warming effect of CO2 since 1897 or earlier and over 100 years ago, we knew that continual burning of coal and other fossil fuels would cause considerable warming.
  - buvanshak 8y ago
    >we knew that continual burning of coal and other fossil fuels would cause considerable warming. Wrong. We didn't know that. We hoped the co2 will be cleaned up by the mechanisms already in place, and we thought the effect would only be temporary. Just like we think the holes caused by the rockets are temporary now, and will not have any cascading effects. Incredibly short sighted and We have learned nothing from history if we continue to reason like this.
    - Robotbeat 8y ago
      Yeah, we did know: https://dotearth.blogs.nytimes.com/2016/10/21/coals-link-to-global-warming-explained-in-1912/ https://dotearth.blogs.nytimes.com/2016/10/21/coals-link-to-...