On April 23, 2014 at 4:58 am EDT, the russian Progress-53 resupply ship, temporarily undocked from the Zvezda russian module on a technology demonstration exercise. This event happened before Expedition 39 US-EVA 26 spacewalk.
The Progress ship backed away to a safe distance from the space station to test upgrades to its Kurs radar navigation system. It will return to a docking with ISS on Friday 25th.
Here is an aft view of the ISS showing the Zvezda module without the Progress 53.
This is an overall view of the ISS without the Progress 53 resupply vehicle. Notice the Dragon CRS-3 capsule berthed to the Harmony module at the front.
Another view of the russian segment showing the Zvezda module without the Progress 53 vehicle.
On April 25, 2014, the Progress-53 resupply vehicle docked to the ISS after a technology rendezvous exercise.
This reference was obtained from Spaceflightnow.com website.