text: If it's not because of the sun , then what causes it ? I could go on but i think you get where i'm coming from. Because he didnt answer every question that could have been answered , im left with curiosity . Other than that , he did a very good job at explaining what happens on Venus . I also dont think it's very smart how he said " Our travels on Earth and beyond should not be limited by dangers and doubts but should be expanded to meet the very edges of imagination and innovation " .