力保登月，美国放弃火星采样返回任务

Core Viewpoint - NASA's Artemis 2 mission is set to launch on February 6, 2024, marking a significant step towards human lunar exploration, while funding for the Mars Sample Return mission has been cut by Congress [1][4]. Group 1: Artemis 2 Mission Details - The Artemis 2 mission will last approximately 10 days and aims to prepare for human landings on the Moon for the first time since the Apollo program [1]. - The mission will involve four astronauts, including NASA's Reid Wiseman and Christina Koch, and will be the first crewed flight of the Space Launch System rocket and Orion spacecraft [1]. - The launch window for Artemis 2 is between February 6 and April 10, 2024, with only 15 potential launch dates due to specific alignment requirements between Earth and the Moon [2]. Group 2: Mission Objectives and Safety Measures - Astronauts will test the Orion spacecraft's control capabilities and perform manual maneuvers in Earth's orbit, preparing for future lunar missions [2]. - The mission includes a "free return trajectory" that ensures astronauts can safely return even if the propulsion system fails, despite higher radiation levels in deep space [2]. Group 3: Challenges and Future Plans - NASA has adjusted the re-entry trajectory of the Orion spacecraft to mitigate safety issues identified during the Artemis 1 mission, particularly concerning the heat shield [3]. - The Artemis 3 mission, which aims to land astronauts on the Moon, is not expected to occur before 2027, with some experts suggesting a more realistic timeline of 2028 [3]. - The final choice of the lunar lander for Artemis 3 remains undecided, with options including SpaceX's Starship and Blue Origin's design [3]. Group 4: Mars Sample Return Mission Funding Cuts - The U.S. Congress has excluded funding for the Mars Sample Return (MSR) mission from the approved budget, signaling a potential termination of the project [4]. - The MSR project, which aims to return samples collected by the Perseverance rover, has faced delays and cost overruns, with total costs estimated at $11 billion [4]. - Despite NASA's efforts to propose a streamlined version of the MSR plan at a cost of approximately $7 billion, it was deemed too expensive and excluded from the new budget [4].