Space.Com is reporting the first launches of two commercial space cargo ships, the SpaceX Dragon and the Orbital Sciences Cygnus, are being delayed to the middle of spring and sometime in August or September.
For the SpaceX Dragon, the problem appears to be the need for more software testing. The cargo version is slated launch atop a Falcon 9 rocket from the Cape Canaveral Air Force Station, fly to the International Space Station, be captured by a robotic manipulator arm, then brought in to dock with the orbiting complex. Once the cargo it is carrying is transferred, the Dragon will undock and return to Earth.
The delays facing the Cygnus are being blamed on the Virginia Commercial Space Flight Authority. The Cygnus is scheduled to launch from NASA's Wallops facility in Virginia. The launch pad that will be used by Orbital's Antares (formally Taurus 2) rocket is not quite ready. When work is completed preparing the launch pad, NASA has to certify it. The process might be finished by late April. Even so, according to Space News, the Antares has to launch on a successful test flight, perhaps in June, before it can fly the first Cygnus mission in late August or early September.
What is the cargo version of the Dragon?
According to SpaceX, the cargo version of the Dragon resembles the planned crewed version, with the exception it lacks a launch escape system, life support and manual controls to allow a crew to take over flight operations is necessary. The Dragon can take 6,000 kilograms of cargo to low Earth orbit and return 3,000 kilograms of cargo back to Earth. It has a payload volume of 10 cubic meters in the pressurized mode and 14 cubic meters in the unpressurized mode.
The Dragon has conducted a test orbital flight and was successfully recovered after a splash down in the Pacific Ocean.
What is the Cygnus?
According to Orbital Sciences, the Cygnus can carry 2,000 kilograms of cargo to low Earth orbit in its standard configuration and 2,700 kilograms in its enhanced configuration. Its payload volume is 19.5 cubic meters in standard mode and 27 square meters in the enhanced mode.
The bottom line
If and when the Dragon and/or Cygnus successfully conduct test resupply missions to the ISS, the spacecraft will be available to take supplies to and from space on a commercial basis. SpaceX is currently working on a crewed version of the Dragon which is hoped will take people to and from destination in low Earth orbit, such as the ISS, relieving America's dependence on the Russian Soyuz for that purpose.
Mark R. Whittington is the author of Children of Apollo and The Last Moonwalker. He has written on space subjects for a variety of periodicals, including The Houston Chronicle, The Washington Post, USA Today, the L.A. Times, and The Weekly Standard.
- SpaceX Dragon