Coming off this year\u2019s manifest changes to the early missions in NASA\u2019s Exploration campaign, the outline and major parameters for the first crewed Orion flight were formally updated to reflect those big picture updates. Exploration Mission-2 is still a test flight to check out Orion with crew system upgrades and circumnavigate the Moon, but the early part of the mission was reworked to take into account the change in configuration of the Space Launch System (SLS) launch vehicle.<\/p>\n
The SLS Boosters and Core Stage will leave its upper stage with Orion attached in a higher insertion orbit on EM-2. After a revised post-insertion sequence, the upper stage will take Orion and crew to an even higher and more elliptical orbit than earlier plans. Following separation from the upper stage, Orion will spend almost a day longer in Earth orbit than previously planned at the start of the mission before leaving Earth for a Lunar flyby.\n<\/p>\n
Transferring higher SLS performance to higher MECO orbit, ICPS<\/p>\n
The Exploration Mission-2 (EM-2) mission has always been the first Orion crewed flight, but the mission profile has gone through multiple revisions over the years, from a high-lunar orbit mission to a cislunar rendezvous with an asteroid redirect spacecraft to the current \u201chybrid triple\u201d outline. Even within that outline, the upper stage for the mission has gone back and forth between the Delta upper stage derivative Interim Cryogenic Propulsion Stage (ICPS) and the Exploration Upper Stage (EUS) that is still in development.<\/p>\n
With early SLS launches moving back to the Block 1 vehicle configuration, the mission baseline was formally revised recently. \u201cIt was an update to switch from the EUS to ICPS, so in that switch because of the performance differences in the stages we had to re-optimize part of the mission around the ICPS,\u201d Nujoud Merancy, NASA Exploration Mission Analysis Lead, explained.<\/p>\n