Exploration Mission 2
Artist's concept of the SLS Block 1A in flight.
|Mission type||Crewed lunar flyby|
|Spacecraft type||Orion MPCV|
|Start of mission|
|Launch date||2023 (planned)|
|Rocket||SLS Block 1|
|Launch site||Kennedy LC-39B|
|End of mission|
|Landing site||Pacific Ocean|
Originally, the crewed mission was intended to collect samples from a captured asteroid in lunar orbit by the now cancelled robotic Asteroid Redirect Mission. As of April 2018, the plan is for a crewed Orion spacecraft to perform a lunar flyby test and return to Earth.
Until 2017, EM-2 was a projected single-launch mission of a Space Launch System Block IB with an Exploration Upper Stage, lunar Block 1 Orion Multi-Purpose Crew Vehicle (MPCV), and a payload insertion of 50.7 t. The plan was to rendezvous with an asteroid previously placed in lunar orbit by the robotic Asteroid Redirect Mission and have astronauts perform space-walks and gather samples. After the cancellation of the Asteroid Redirect Mission, it was proposed in 2017 to fly an eight-day mission with a crew of four astronauts, sent on a free return trajectory around the Moon. Another proposal suggested in 2017 was to take four astronauts aboard Orion on an 8-to-21-day trip around the Moon to deliver the first element of the Lunar Orbital Platform-Gateway (LOP-G).
In March 2018 it was decided to launch the first Lunar Gateway module on a commercial launch vehicle because of delays in building the mobile launch platform needed to hold the more powerful 'Exploration Upper Stage'. As of 2018[update], the EM-2 mission plan is to send four astronauts in the first crewed Orion capsule into a lunar flyby for a maximum of 21 days. The mission profile is a multi-translunar injection (MTLI), or multiple departure burns, and includes a free return trajectory from the Moon. Basically, the spacecraft will orbit Earth twice while periodically firing its engines to build up enough velocity to push it toward the Moon before looping back to Earth.
In 1968, the Apollo 8 mission, crewed by 3 astronauts, was designed to flight test a Command Service Module beyond low Earth orbit. Although similar to EM-2 in that it was crewed and did not land on the Moon, it differed by entering lunar orbit for an extended stay.
In 2005, the company Space Adventures announced plans to take two tourists within 100 km (62 mi) of the lunar surface using a Soyuz spacecraft piloted by a professional cosmonaut. The mission, named DSE-Alpha, has been priced at US$150 million per seat and is expected to last 8–9 days when scheduled. Company CEO Eric Anderson stated in 2011 that one seat had been sold, but the launch date has continually slipped since the second seat remains unsold as of 2017[update].
A proposed late 2018 SpaceX Lunar Tourism Mission would have been similar to EM-2, with two space tourists paying for a free-return loop around the Moon and back to Earth, using the Crew Dragon capsule and launched on the Falcon Heavy. After the first flight of Falcon Heavy in 2018, SpaceX announced that Falcon Heavy would not be used for crewed flights to focus their future development on BFR.
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