[ubuntu] Hard drive problem. topic

See attached photos below.
There are 2 hd's on this Ubuntu 14.04LTS system.
However, as shown in photos, one disappeared.
It's an 80gb used for backup.
How can it be restored without data loss. Not the end of the world if data lost. It's backup elsewhere also.

Thanks for reading.
dlw

Attached Images

• 
  
  gp2.png
  (39.5 KB)
  
• 
  
  gp1.png
  (29.9 KB)