You might be able to open a JT but you cannot directly open NX in SolidWorks to my knowledge (different Kernals).
NX 12 | SW 2017 | Creo 4 | TcUA 11.4
The reason I ask is this.
In NX, I search for an Item, I find it, it is built in Solidworks, I can add it into an NX assembly.
Can't I do the same?
No. You cannot. It is a limitation of Solidworks. It cannot open either NX nor JT files. You'd have to export a Parasolid file from NX and import it to Solidworks.
Both Randy and Larry are right. You cant open a NX or JT file directly in SW.
Here I hope to shed some light on why you can see the SW model when you do a search in NX.
I have some cage nuts here as an example. I have master the part in SW and when I saved into my TcRS environment I had the generate JT option turned on.
I then open the the part in NX, but what it did was grab the JT (or you will see MultiCAD in the list). So the 1st feature in the NX feature navigator is the JT_ASSOCIATIVE_BODY.
This really great, because if I change the SW part, all I have to do in NX is use the update button in the Displayed Properties window to have the part update in NX as well.