Magnitude of the Earth with vs. without humans

[mithridates]

Two questions actually:<br />1) How much has human development (namely city lights at night) changed the magnitude of the Earth from the outside? How much fainter would the Earth be from Mars for example without any cities?<br />2) How much development / change in albedo would there have to be for Ceres to become visible to the naked eye?<br /><br />This question came to me when posting on the other thread about Ceres which seems to be a worthwhile destination for exploration, but psychologically it would be a bit sad not to be able to see with one's eye the destination that people have gone to. <div class="Discussion_UserSignature"> <p>----- </p><p>http://mithridates.blogspot.com</p> </div>

 

[vogon13]

I don't have the article at hand, but at some of the mercury wavelengths, (IIRC) earth out shines the sun.<br /><br /><br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>