Sirius_Alpha Admin
Number of posts : 4319 Location : Earth Registration date : 2008-04-06
| Subject: CO as a limit to M dwarf habitability? 24th June 2019, 12:09 am | |
| Schwieterman, et al. argue that CO is likely to be much higher in the atmospheres of M dwarf habitable zone planets, which may prove toxic for complex life as it interferes with hemoglobin's ability to transfer oxygen (namely because CO is much more efficient at bonding to it). A Limited Habitable Zone for Complex Life https://iopscience.iop.org/article/10.3847/1538-4357/ab1d52ScOn the other hand, Howell points out alternative CO-friendly oxygen carriers exist. Comment on "A Limited Habitable Zone for Complex Life" https://iopscience.iop.org/article/10.3847/2515-5172/ab2a76 - Quote :
- There are two other well-characterized oxygen-carrying metalloproteins in invertebrates that do not exhibit hemoglobin's sensitivity to CO (reviewed comprehensively in Kurtz 1999, 2003). One is hemerythrin, found in certain worms and brachiopods, which also binds oxygen via iron but with very different chemistry than hemoglobin. The other is hemocyanin, found in certain arthropods and molluscs, which binds oxygen via copper, again with distinctive chemistry.
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Lazarus dF star
Number of posts : 3337 Registration date : 2008-06-12
| Subject: Re: CO as a limit to M dwarf habitability? 24th June 2019, 3:55 pm | |
| Well there goes my plan to evacuate to TRAPPIST-1. | |
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