Space Shuttle Discovery and STS-133

I just watched the live feed of Space Shuttle Discovery taking off for the last time with the lift off of STS-133.  It was a little bittersweet in my opinion.  This will be Discovery's last venture into space. 

It is Discovery's 39th flight, 35th to the ISS.

It is the 164th American manned mission to space.

The 20th mission since the Columbia disaster and the 108th mission since the Challenger disaster.

Let's hope this is a safe trip and everything goes as planned.