NASA's Space Launch System rocket, currently in development, will be the largest rocket ever built when completed. The agency was planning an unmanned test flight for the rocket in September 2018, but now NASA is considering launching with a crew on the SLS's first flight, known as Exploration Mission-1 or EM-1.
Acting NASA Administrator Robert Lightfoot announced that the agency would be conducting a feasibility study for a crewed SLS launch during a conference in Washington D.C. this morning, according to the NASA press office. The conference is "for manufacturers that are helping build the SLS, our Space Launch System rocket and Orion spacecraft."
NASA sent Popular Mechanics this statement regarding the first SLS flight:
Acting Administrator Robert Lightfoot has asked Bill Gerstenmaier, associate administrator for the Human Exploration and Operations Mission Directorate, to initiate a study to assess the feasibility of adding a crew to Exploration Mission-1, the first integrated flight of SLS and Orion. The study will examine the opportunities it could present to accelerate the effort of the first crewed flight and what it would take to accomplish that first step of pushing humans farther into space. The SLS and Orion missions, coupled with record levels of private investment in space, will help put NASA and America in a position to unlock the mysteries of space and to ensure this nation's world preeminence in exploring the cosmos.
Lightfoot also wrote in a NASA "agency update" memo: "I know the challenges associated with such a proposition, like reviewing the technical feasibility, additional resources needed, and clearly the extra work would require a different launch date."
It is unclear how long the launch will be delayed if NASA does decide to proceed with a crewed SLS launch for the rocket's maiden flight. EM-1 was originally going to launch an unmanned Orion capsule into orbit around the moon. The spacecraft would then return to Earth three weeks later, using parachutes to land in the ocean.
The first crewed mission of the Orion spacecraft was slated to be the second launch of SLS, and in late 2016, NASA reined in that mission plan by deciding that EM-2 would not orbit the moon, but rather loop around the far side once and then return to Earth. Exploration Mission-2 was scheduled for 2021, as it requires a larger version of the SLS rocket, called Block 1B, that uses a more powerful second stage that has yet to be built. It hasn't been announced where the astronauts will fly if NASA upgrades EM-1 to a crewed mission, but it seems possible that the first flight would loop around the moon according to the plan for EM-2, assuming the construction of Block 1B can be expedited.
The potential shift in plans for the SLS, to skip the unmanned flight test, are likely due to agendas set by the new Trump administration's NASA transition team. A recent report also announced that the Trump administration is considering a proposal to launch another Hubble Space Telescope servicing mission. The administration is reportedly interested in pursuing missions that expand public-private partnerships in the spaceflight industry and can be achieved within the president's first term.
Whether or not NASA will be able to leapfrog the unmanned SLS flight test is another matter. Two Government Accountability Office reports suggest that the projected launch date of both EM-1 and EM-2 could be unrealistic, as both the SLS rocket itself and the launchpad ground systems required may not be ready in time. If NASA adds a crew to EM-1, the additional costs and delays could push the flight back even further, not to mention the risk of flying astronauts on an untested rocket.
As a NASA Johnson Space Center employee told The Verge, ""It would definitely be a shift in how we do things."