The first object with some "haze" around it is the Discovery dumping excess water (weight) before returning to Earth. Discovery is "followed" by the ISS.
Further examples of this event can be seen here:
http://www.twanight.org/newTWAN/photos.asp?ID=3003175
Some information regarding the water dump can be found here:
http://www.spaceweather.com/archive.php?view=1&day=09&month=03&year=2011
Cheers
