Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
The US scientific community continues to make heavy weather of the policing of scientific misconduct, chiefly because federal agencies cannot act without being forced to be courts of law. But now there is a chance to undo one mistake.
The question of why the sky is dark at night is a textbook problem, but textbook answers may still miss the point. The problem is that of determining which is the more dominant of the two preferred solutions.
