Re: NASA's Warp Drive - update
These lifeforms could be something as small as a bacteria, or akin to us - a thinking and reasoning species. These are the known threats.
Especially when our daring astronauts will be told "You are too immature. Go back to your planet and grow up before you leave your cradle again..."
That would be quite a frustrating moment.
"The first duty of every Starfleet officer is to the truth" Jean-Luc Picard
"We can't solve problems by using the same kind of thinking we used when we created them." Albert Einstein