A record supply load won't reach the International Space Station as scheduled

"The damage occurred during the shipment of the spacecraft's pressurized cargo module from its manufacturer in Italy. While Northrop Grumman hopes to repair the module and launch it on a future flight, officials decided it would be quicker to move forward with the next spacecraft in line for launch this month. This is the first flight of a larger model of the Cygnus spacecraft known as the Cygnus XL, measuring 5.2 feet (1.6 meters) longer,"

"The main engine on the Cygnus spacecraft burns a mixture of hydrazine and nitrogen tetroxide propellants. This mixture is hypergolic, meaning the propellants ignite upon contact with one another, a design heralded for its reliability. The spacecraft has a separate set of less powerful reaction control system thrusters normally used for small maneuvers, and for pointing the ship in the right direction as it makes its way to the ISS."

"Unlike SpaceX's Cargo Dragon spacecraft, the Cygnus is not designed to return to Earth intact. Astronauts fill it with trash before departure from the ISS, and then the spacecraft heads for a destructive reentry over the remote Pacific Ocean. Therefore, a problem preventing the spacecraft from reaching the ISS would result in the loss of all of the cargo onboard."

Damage to a pressurized cargo module during shipment from its manufacturer in Italy prompted officials to advance the next Cygnus spacecraft for launch while repairs are considered. The flight uses the larger Cygnus XL, 1.6 meters longer and carrying about 33 percent more cargo, delivering the heaviest commercial load to the ISS to date. The main engine burns hypergolic hydrazine and nitrogen tetroxide; smaller reaction control thrusters handle fine maneuvers. If the main engine is unusable, those thrusters might be used for gradual orbital adjustments, though viability is unclear. Cygnus is not designed to return intact, so lost shipments would burn up on reentry. NG-23 carries fresh food, experiments, and spare parts for station systems.

Read at Ars Technica