The Artemis program, which would take humans back to the moon, will get a kickstart later this year with the launch of Artemis I. NASA will perform the launch from Kennedy Space Center in Florida with its Space Launch System (SLS) megarocket on its first launch. The rocket, which is currently in development, will get a total of 73 launch opportunities when the agency plans to launch it this year.
NASA on Monday released the full timeline for the Artemis I mission and the potential launch opportunities the agency could use to launch the rocket to the moon. According to NASA’s schedule, the first launch window begins on July 26 and extends through December 23, 2022. Let’s take a look at the potential launch opportunities flagged by NASA.
July 26 – August 10: 13 entries except August 1st, 2nd and 6th
August 23 – September 6: 12 starting possibilities except on August 30th and September 1st
September 20 – October 4: 14 starting possibilities with the exception of September 29th
October 17 – October 31: 11 starting possibilities except on October 24th, 25th, 26th and 28th
November 12 – November 27: 12 starting possibilities except on November 20th, 21st and 26th
December 9 – December 23: 11 starting possibilities except on December 10th, 14th, 18th and 23rd
Parameters that dictate launch options
Although the number of launch windows seems sufficient for a single launch, NASA has highlighted some key parameters that determine launch opportunities within the above timeframe. To understand these parameters, we must first note that the Orion unmanned spacecraft, ready for launch during Artemis I, is sent into a special path called Distant Retrograde Orbit (DRO). This orbit is said to be stable due to the balance created by the gravitational forces of the Earth and Moon, and also allow a spacecraft to fly with lower fuel costs. Tap here to learn more about this orbit and Orion’s mission profile.
Now, taking into account the position of the moon during its lunar cycle, NASA is looking for the perfect day for the Orion capsule to be easily inserted into the DRO. The upper stage of the SLS rocket must perform a large movement called translunar injection, or TLI, that sends the capsule 3,86,242 kilometers from Earth and another 64,373 kilometers beyond the moon.
Another important parameter is the consideration of the trajectory of the Orion spacecraft when pushed into space. The trajectory must be such that the spacecraft is not left in the dark for more than 90 minutes. Orion needs sunlight to power its solar panels to generate electricity and maintain an optimal temperature range. The start date, which allows a skip-entry maneuver, is another important parameter.
This maneuver is a re-entry technique in which a spacecraft dives into the upper portion of Earth’s atmosphere and uses that atmosphere along with the capsule’s buoyancy to simultaneously slow down and bounce out of the atmosphere and then re-enter for the final descent and splashdown. NASA says that “the technique will allow engineers to pinpoint the location of Orion’s splashdown and will help reduce astronauts’ aerodynamic breaking loads on future missions.” The fourth and final parameter is that the launch date must provide daylight conditions during the Orion splashdown when recovery personnel locate, secure, and retrieve the spacecraft from the Pacific Ocean.