No one has ever landed on venus so the author is saying this because no space ship has survived landing for more than a few hours. maybe the issue explains why not a single spaceship has touched down on veunus more than three decade, venus really is a challanging planet for people to study.

Venus has a thick atmosphere of almost 97 percent carbon dioxide covers venus, even more challenging are the clouds of highly corrosive sulfric acid in the atmophere. On the surface, temperatures average over 800 degress F and the pressure is 90 times greater than our planet. The conditions are extreme than anything humans encounter, due to the pressure and th heat of venus.

Beyond the pressure and the heat venus has geology and wather present additional impediments like erupting volcanoes, powerful earthquakes and frequent lightning strikes to probes seeking to the land surface. It'll be dangerous even trying to live on venus but if you want to live on vnus be prepared for these desasters. Like for example our jet airplanes travel at a higher altitude to fly over many storms, a vehicle hovering over venus would advoid the unfriendly ground conditions by staying up and out of their way.

This is why NASA is working on a wat to approach and study venus, like some simplified electronics made of silicon carbide have been tsted in a chamber simulating the chaos of venus surface and have lasted for three weeks in the conditions of venus. Imagine a blimp like vehicle hovering 30 or so miles above the rolling venusian landscape, that'll be very cool and amazing to see and watch on TV.

Just if you ever think about wanting to go visit venus..make sure you bring lots of water and a cooling suit that'll cool you when you attempt to walk along across venus.