What people do not understand, they start to fear of it.
Just think of one example from your experience:
"Human do not know about space long time ago yet they face their fear and now we are able to study the solar system and so on."
To overcome your fear,
Face it slowly,
Step by step try to understand your fear,
Study the nature of your fear,
Understand your fear,
Face it slowly,
Convince yourself by doing a little effort to your fear,
Accumulate the confidence against your fear,
Face it slowly,
Don't avoid your fear,
As you do so,
You will NEVER overcome your fear.
Please,
Face it, Understand it, Do it!
You will realize your fear today might not be that scary tomorrow after all.
Cheers~