Managers in NASA's Human Exploration and Operations Mission Directorate have initiated a formal request to change the mission plan for the agency's first flight of the Space Launch System (SLS), Exploration Mission (EM) 1 in 2017. The flight will carry an uncrewed Orion spacecraft to a deep retrograde orbit near the moon, a stable orbit in the Earth-moon system where an asteroid could be relocated as early as 2021.
The 25-day mission will send Orion more than 40,000 miles beyond the moon and allow engineers to evaluate the performance of SLS and assess the systems designed to support a crew in Orion before the capsule begins carrying astronauts. The plan will provide NASA with the opportunity to align the flight more closely with the agency's mission to send humans to a relocated asteroid.
The previous plan for the first test flight of the SLS heavy-lift launch vehicle was to send Orion on a 10 day mission to high-lunar orbit to evaluate the fully integrated Orion and SLS system.
"We sent Apollo around the moon before we landed on it and tested the space shuttle's landing performance before it ever returned from space." said Dan Dumbacher, NASA's deputy associate administrator for exploration systems development. "We've always planned for EM-1 to serve as the first test of SLS and Orion together and as a critical step in preparing for crewed flights. This change still gives us that opportunity and also gives us a chance to test operations planning ahead of our mission to a relocated asteroid."
The request will be reviewed later this summer by a range of other NASA officials.
The agency announced in April a plan to find and redirect an asteroid to a stable point near the moon where astronauts can visit and study it as early as 2021.
NASA's asteroid initiative leverages human and robotic exploration activities while also accelerating efforts to improve detection and characterization of asteroids. It aligns current and future work in NASA's Science, Space Technology and Human Exploration and Operations mission directorates to achieve the space goals set by the administration.
Across the U.S., engineers at NASA and its contractors are making progress to develop and test Orion and SLS. Orion will first launch on a test flight in September 2014. A United Launch Alliance Delta IV Heavy rocket will send the spacecraft to an altitude of 3,600 miles above Earth's surface. It will reenter the atmosphere at speeds of about 20,000 mph and endure temperatures of 4,000 degrees Fahrenheit.
The test flight is designed to evaluate the performance of Orion's heatshield and other systems.
The SLS program currently is undergoing an extensive review process to ensure that every element of the launch vehicle can be successfully integrated. The review process, called the Preliminary Design Review, is scheduled for completion later this summer.
SLS will be NASA's most capable rocket ever and enable missions to new destinations in the solar system.