Can I open 2 unity projects at the same time?

I am using Unity 5.0 and Mac OS 10.10.2. A few answers are found by googling, but didn’t work.
How can I open 2 unity windows? Thanks in advance for any help.

Simply fire from Terminal:

open -na Unity


Go in Unity Menu - > select preferences → check Always show project wizards.

Then go in applications → right click on unity in Unity folder → Select show package contents → Go in MacOS folder → Double click unity file. This will open terminal and then project selection wizard.