April 9, 2021 updates Posted on April 9, 2021 by Doug Loss Revision of “Dependence of climate states of gray atmosphere on solar constant: From the runaway greenhouse to the snowball states” by Ishiwatari et al. (2007) https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019JD031761 Discovery of the First Interstellar Comet and the Spatial Density of Interstellar Objects in the Solar Neighborhood https://link.springer.com/article/10.1134%2FS0038094621020027 Extending a grid of hydrodynamic planetary upper atmosphere models https://arxiv.org/abs/2104.03796 The Trouble with “Puddle Thinking”: A User’s Guide to the Anthropic Principle https://arxiv.org/abs/2104.03381