Why is the texture preview (in my texture editor) not normalized?

Hey everyone,

I'm new and currently trying to follow a tutorial in which his texture looks like that:

https://imgur.com/a/SCCxV

When I re-created it, it looked like that in my Content Browser thumbnail - all good:

https://imgur.com/Cf0Bn3T

However, in my Texture editor it looks like this:

https://imgur.com/qE3Kfek

which really is a little irritating to work with. As he pans around his sphere, you can clearly see it has an inner-to-outer fade (just as in my thumbnail, too) - when I'm panning mine it's clearly having the gradient mapped around the sphere.

Is there anything I miss?

The tutorial I am talking about:

https://docs.unrealengine.com/latest/INT/Videos/PLZlv_N0_O1gYDLyB3LVfjYIcbBe8NqR8t/7hC_QT4GLiU/index.html

The first 01:30min are already enough. Could anyone confirm that his preview looks like this, too?

Thanks a lot in advance!