Why can't this be another structural isomer of ethanol?

Are the two structures depicting the same molecule? Why? Why not?


[![Ethanol "isomers"](https://i.stack.imgur.com/DeEmk.png)](https://i.stack.imgur.com/DeEmk.png)




Try to imagine it in a 3D fashion. You can look it at [molcalc.org](http://molcalc.org/calculation/006f345b78127258186ad02dcf30e0ae). The molecule rotates around the $\ce{C-C}$ bond converting one structure into the other. These rotations are very fast. 


Another point is, that the representations you chose are 2D, so the could still represent the same molecule:


[![same molecule different angles](https://i.stack.imgur.com/XVerW.png)](https://i.stack.imgur.com/XVerW.png)


 18