Orbital ATKs Cygnus spacecraft delivered more than 7.6 metric tons of cargo to the International Space Station on 22 April. Orbital ATKs seventh cargo delivery flight to the station launched on 18 April on a United Launch Alliance Atlas V rocket from Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida, USA. The spacecraft will remain at the space station until July before its destructive re-entry into Earths atmosphere. The mission, which is under NASAs Commercial Resupply Services contract, will support dozens of new and existing investigations as Expeditions 51 and 52 contribute to approximately 250 science and research studies. Among the equipment on board the flight were 28 cubesats, which, as part of the NanoRacks-QB50 project, will be used to study the upper reaches of Earths atmosphere over the next one to two years. The QB50 satellites conduct coordinated measurements on a poorly studied and previously inaccessible zone of the atmosphere referred to as the thermosphere. The project monitors different gaseous molecules and electrical properties of the thermosphere to better understand space weather and its long-term trends.