Picture courtesy NASA/Bill Ingalls

The weather looks good for the launch of NG-12 commercial resupply mission to the International Space Station on Saturday morning at 9:59 am.  The forecast is calling for clear skies and light winds.   After loading the Cygnus spacecraft with time-sensitive cargo and returning the Antares to a vertical position Friday morning,, final pre-launch checks will begin which will hopefully lead to a Saturday morning lift off. According to Spaceflight Now magazine, the launch team will then oversee final activation, readiness checks and fill the Antares rockets first stage with kerosene and liquid oxygen propellants before the liftoff which is scheduled at the moment that Earth’s rotation brings the Wallops launch site under the International Space Station’s ground track.

Saturday’s scheduled launch will mark the 11th flight of an Antares Rocket since 2013 and the sixth to fly in the Antares 230 configuration with two Russian made RD-181 main engines which replaced the AJ26 first stage engines used on the first five Antares missions.

The NG-12 mission is set to deliver some 8200 pounds of supplies and experiments to the space station, nearly 10 percent more than the previous Antares/Cygnus flight.   The cargo will set a new record for the heaviest payload launched by a commercial U.S. resupply ship.

The Cygnus spacecraft from Northrup Grumman’s previous cargo flight NG-11 has remained in orbit since leaving the space station on August 6 to begin an extended demonstration mission. The company wants to demonstrate its capability to operate both space crafts simultaneously.

NASA has ordered six additional Cygnus cargo missions Northrup Grumman under the current contract. All six are slated to launch on Antares rockets from Wallops Island.

Source: Spaceflight Now magazine