Space Launch System: First launch of Nasa's most powerful rocket could be shifted to 2020

The first launch of Nasa's Space Launch System (SLS) – the space agency's massive rocket for missions to the Moon and beyond – could be postponed to June 2020, Nasa indicated in a release on Thursday, 9 November.

The possible change in the launch timeline came to light after the agency's "comprehensive review" of its schedule. This helped Nasa identify a number of risks that could push the launch date back. However, as none of those issues have come up yet, the agency is still working towards a launch in December 2019 – the current official date.

Nasa administrator Robert Lightfoot said, "Since several of the key risks identified have not been actually realised, we are able to put in place mitigation strategies for those risks to protect the December 2019 date."

In order to address the identified risks, Nasa has established production performance milestones for the SLS core stage. This, as the agency says, would drive efficiency and increase confidence for future hardware builds.

The first configuration of the SLS vehicle, called Block 1, will use twin five-segment solid rocket boosters and four RS-25 liquid propellant engines, and a modified version of an existing upper stage.

The 322 feet vehicle will stand taller than the Statue of Liberty and produce a total thrust of 8.8 million pounds at lift-off – making it Nasa's most powerful vehicle ever. The agency recently shared an animated video depicting what the blast-off might look like.

It is also worth noting that the first mission of the SLS, dubbed EM-1, won't fly any astronauts. It will lay the groundwork for future missions, which would see the vehicle taking astronauts in the Orion spacecraft to deep space, starting 2023.

Originally scheduled for 2016, the launch of the SLS has seen a number of delays over the years. The most recent setback came earlier this year when the launch was pushed from November 2018 to December 2019 due to a number of issues, including a limited budget, problems related to the rocket's core stage and the damage caused by a tornado at its Michoud Assembly Facility in New Orleans in February.

Though Nasa had earlier apprised the US Congress that its launch target revolves around October 2019, it did not confirm the exact timeline before Thursday's release, Space News reported.

Among other things, the agency is also looking forward to testing the Orion spacecraft's launch abort system – the emergency system which consists of a tiny rocket meant to carry Orion and the crew away from SLS in case it malfunctions. The system is scheduled to be tested in April 2019.