Orion moon mission SLS
An artist's rendition of Nasa's Space Launch System rocket in its latest configuration following its critical design review. Credit: Nasa.

Nasa is exploring the idea of using a commercial rocket to launch its Orion crew capsule around the Moon next year as it is struggling to get the Space Launch System (SLS) ready in time.

The agency planned to use the SLS, which is based on a large two-stage rocket design, to launch astronauts towards the Moon and even Mars. Boeing is the prime contractor for the SLS rocket.

The SLS was supposed to launch the Orion crew capsule. However, increasing delays and cost overruns have meant the launch system is highly unlikely to be ready in time to carry out the planned task.

The first Orion mission is an uncrewed mission, known as Exploration Mission-1 (EM-1), which will be followed by a crewed SLS/Orion mission EM-2.

At a Senate hearing, Nasa administrator Jim Bridenstine stated that the agency needs to consider all possible alternatives to ensure the planned launch of the Orion capsule takes place.

“The challenge is we don’t have a rocket right now that can launch Orion and the European Service Module around the Moon.”

Bridenstine said: “We need to consider as an agency all options to accomplish that objective. Some of those options would include launching the Orion Crew Capsule and European Service Module on a commercial rocket.

The European Service Module component is designed to provide power and propulsion for the capsule.

Commercial rockets available in the market do not have the power needed to launch both Orion and its service module.

Bridenstine added: “The challenge is we don’t have a rocket right now that can launch Orion and the European Service Module around the Moon.”

This implies that Nasa will have to rely on two rockets. In this scenario, the first rocket would be used to launch the Orion capsule and its service module. The upper stage that provides power to boost the capsule and module to the Moon would be launched aboard the second rocket.

Then, the upper stage would dock with Orion and its service module in orbit before they make their onward journey to the moon.

If Nasa chooses to go for a commercial rocket for the launch, United Launch Alliance and SpaceX could be the likely contender to win the deal.