If you're an Ubuntu user and need to open and view .obj files, you're in luck. Ubuntu, being a popular Linux distribution, has several options for opening 3D model files such as .obj. Here are a few ways to do it:

1. Use MeshLab: MeshLab is a free and open-source 3D model processing software that supports the .obj format. You can easily install MeshLab on Ubuntu using the Software Center or the terminal. Once installed, you can open .obj files and explore the 3D models with its intuitive interface.

2. Install Blender: Blender is a powerful 3D modeling and animation software that also supports the .obj format. You can install Blender on Ubuntu either through the Software Center or by using the terminal. Once installed, you can import .obj files into Blender and manipulate them as needed.

3. Try FreeCAD: FreeCAD is a parametric 3D modeler that also supports the .obj format. It is available for Ubuntu and can be installed through the Software Center or the terminal. FreeCAD provides tools for viewing and editing .obj files, making it a great option for working with 3D models in Ubuntu.

By using these tools, you can easily open and view .obj files on your Ubuntu system, whether you're a 3D modeler, designer, or just need to view 3D models for a project. Each of these software options provides a user-friendly interface and the necessary tools to work with .obj files seamlessly.