The SLS Saga: The Inaugural Launch
NASA T-38s Flying Above Artemis 1’s SLS Rocket on Launch Pad 39B (Courtesy of NASA)
“Fly me to the Moon. Let me play among the stars.”
***Special Edition in Anticipation of Artemis 1, the first launch of the SLS Program. For additional posts, please visit the SLS Saga microsite here.***
**UPDATE @ 11/15, 11:30 pm PT:*** And at local time 1:48 am EST on 11/16 (10:48pm PT on 11/15), SLS blasted off for the very first time to the Moon. It is quite a sight to behold: a giant rocket igniting its engines that produced a giant red ball of fire that pierced the darkness of the night. While it has been a program marred by delays, this is still a shining defining moment for America’s next rocket launch system to the Moon and beyond.
**UPDATE @ 11/15, 9:30 am PT:*** I have been under the weather and had hesitated in updating NASA’s next scheduled launch date for the SLS rocket. But it looks like it is still on! NASA will attempt to launch the SLS rocket tonight (November 15) during a two-hour launch window that opens at 10:04pm pacific time. Stay tuned!
**UPDATE @ 10/23, 1:30 pm PT:*** NASA will now target a local time of shortly after midnight on November 14th (Monday) for the first launch of the SLS mission. There will be a 69 minute window available for this launch. The rocket will be rolled back to the launchpad in preparation for this launch as early as November 4th.
**UPDATE @ 9/26, 2:30 pm PT:*** Well, it looks like NASA will not be launching SLS for Artemis 1 in September after all. The delay this time is not due to mechanical issues but weather issues: Hurricane Ian is bearing down on the Florida coast. Because of the hurricane, NASA will need to roll SLS rocket back into the Vehicle Assembly Building, which means that the rocket will not be ready for launch for quite a while. Looks like the saga continues.
**UPDATE @ 9/22, 6:00 pm PT:*** Yesterday, NASA conducted tanking tests to see if the leak issues have been properly fixed. Despite a few leaks, it appears that NASA believes that the test met its objectives. But, NASA will review the data further before deciding whether it’s go for flight on September 27th.
***UPDATE @ 9/15, 9:00 am PT:*** NASA has announced that it will next attempt to launch the SLS rocket on Tuesday, September 27 with a launch window starting at 8:37 am PT. It will also review a back-up launch date of October 2nd. Before this launch attempt, NASA will also do a cryogenic demonstration test before the next attempt to ensure that the leaks have been fixed.
***UPDATE @ 9/12, 9:00 am PT:*** NASA has finished repairing the leaky seals that caused issues related to SLS’s hydrogen quick-disconnect fueling lines. A fueling test is now on deck, which could happen as early as September 17th.
***UPDATE @ 9/8, 12:00 pm PT:*** It looks like NASA will attempt to fix the leaky seal (quick disconnect) on the pad rather than rolling the vehicle back to the assembly building. Assuming the fix goes well and NASA gets an extension on the Flight Termination System waiver (testing of the battery that is needed to destroy the rocket if it veers off course during launch), the next attempt could come as early as September 23. Though I am not sure if it is wise to waive it too long and not have a working self-destruct system given all of the problems we have seen so far….
***UPDATE @ 9/3, 12:00 pm PT:*** Unfortunately, an accidental pressurization issue during the tanking process caused a persistent liquid hydrogen leak problem. The second launch attempt is now officially scrubbed. For an in-depth examination of this issue, see Eric Berger’s great article on this topic.
***UPDATE @ 8/30, 6:00 pm PT:*** NASA is now targeting a new launch date of Saturday (September 3rd) during a 2-hour launch window that starts at 18:17 GMT (2:17 pm ET / 11:17 am PT).
***UPDATE @ 8/29, 7:05 am PT:*** NASA has officially scrubbed SLS first launch attempt. This is due to an “engine bleed” issue on one of the main RS-25 engines (engine number 3) attached to the core stage. Basically engine number 3 could not be properly chilled/cooled down prior to ignition.***
That long awaited day for the SLS rocket is almost here! It looks like SLS is on the precipice of its first ever mission. To be completely honest, I had serious doubts about SLS being able to perform its inaugural launch this year, much less before the end of August. But it looks like NASA is going to pull a rabbit out of the hat this time around. The space agency is setting the launch of Artemis 1 for August 29, 2022 within a 2-hour launch window that starts at 12:33 UTC (8:33 am Eastern / 5:33 am Pacific).
With SLS’s inaugural launch being nigh, I think it is fitting to commemorate this mission with a special post focused specifically on Artemis 1 as part of my SLS Saga series. I will also try to keep this post updated by live-blogging SLS’s inaugural launch (similar to what I did with the inaugural launch of NASA’s Commercial Crew Program).
Artemis 1’s Flight Plan
Artemis 1 is anticipated to launch on August 29, 2022 from the historic Launch Complex 39Bat the Kennedy Space Center, a launch site for the Apollo Program. Artemis 1’s mission profile has changed a little bit since I first wrote about this mission back in January 2018. In fact, back then, the mission was still called Exploration Mission 1 (the Program’s name change to “Artemis” wasn’t even announced until May 2019).
Artemis 1, SLS’s inaugural mission, will primarily serve as an unmanned test flight of the SLS systems, including its Orion space capsule. Powered by its core stage, two boosters and four RS-25 engines, the rocket is expected to reach Max-Q within 90 seconds of launch. At around the 2-minute mark past launch, the boosters should deplete their fuel and separate from the rocket. Then, the core stage and the rocket’s RS-25 engines should use up all of their fuel at around the 8-minute mark and will also separate after main engine cut off. After reaching Outer Space, the capsule is anticipated to make one orbit around the Earth to deploy its solar arrays and fire up its Interim Cryogenic Propulsion Stage (ICPS) for a trans lunar injection burn. The ICPS is expected to separate from the Orion capsule 2 hours after launch and will then, through the course of this trip to the Moon, deploy several CubeSats as part of Artemis 1’s secondary mission objectives.
Once near the Moon and during its first lunar flyby, the Orion capsule will adjust its trajectory via correction burns and, with the assistance of lunar gravitational force, enter into a distant retrograde orbit (DRO) around the Moon. Artemis 1 will spend a half or 1.5 revolutions in DRO before starting its return trajectory correction (RTC) burns for its return to Earth. Once near Earth, the Orion capsule will detach its service module and the crew module portion will enter the Earth’s atmosphere. To successfully finish the mission, the capsule will splash down in the Pacific Ocean just off the coast of San Diego.
Artemis 1 Facts
If everything goes according to plan and the SLS rocket makes its August 29th launch date, Artemis 1 is anticipated to last 42 days, 3 hours, and 20 minutes. The Orion capsule will make its Pacific Ocean splash down on October 10, 2022. By the end of the mission, the crew module part of the Orion capsule will have travelled over 1.3 million miles (2.1 million kilometers).
Artemis 1 is anticipated to take its Orion capsule as close as to within 60 miles (97 kilometers) above the lunar surface. While not expecting to land, its primary destination is a distant retrograde orbit in the area around the Moon. While in this orbit, the capsule is expected to travel 40,000 miles (64,000 kilometers) past the far side of the Moon and could be nearly 280,000 miles (450,000 kilometers) away from Earth.
If Artemis 1 does not launch on August 29th, it also has backup launch dates of September 2nd, 2022 (Friday) at 17:48 GMT (12:48 pm ET / 9:48 am PT) and September 5th, 2022 (Monday) at 22:12 GMT (5:12 pm ET / 2:12 pm PT). For the September 2nd launch date, it will likely only have a 39-day mission and will splash down on October 11th. If it launches on September 5th, Artemis 1 should be able to keep to its original 42-day mission plan.
Because Outer Space travel is hard and still very unpredictable, the Artemis 1 mission timeline can still vary even if it launches on August 29th. Total mission time can go from as short as 26 days to as long as the anticipated 42 days. Outbound transit to the Moon can last somewhere between 8 to 14 days, while the stay in Distant Retrograde Orbit will be anywhere from 6 to 19 days. The return transit back to Earth is anticipated to take 9 to 19 days.
Artemis 1 Rocket Specifications
Artemis 1’s rocket specifications has not changed much from when I first wrote about its specifications back in January 2018. It is still the block 1 version that stands 322 feet tall with the Orion capsule taking up 26 feet of that height.
Artemis 1’s rocket, Block 1 version of the SLS rocket, will have (1) a core stage that has a height of more than 200 feet and a diameter of 27 feet, (2) four RS-25 engines designed by Aerojet Rocketdyne, (3) 2 five-segment solid rocket boosters that is each 177 feet long and 12 feet in diameter, weighing about 1.6 million pounds. Block 1 will also use an Interim Cryogenic Propulsion Stage (ICPS) that will be powered by one RL10B-2 engine also designed by Aerojet Rocketdyne.
Artemis 1’s SLS rocket will weigh 5.75 million pounds fully fueled and will generate 8.8 million pounds of thrust at liftoff. It can launch 70 metric tons (77 tons or 154,000 pounds)—carrying more than three times the mass of the Space Shuttle—of which 59,000 pounds could be used as payload space.
Artemis 1 Payloads
While no humans will be onboard Artemis 1, this mission will have several special guests onboard, including:
Mannequins: three human-sized mannequins will be onboard to collect critical information for subsequent manned flights. As a tribute to Arturo Campos, a NASA engineer, the mannequin in the commander seat is named Moonikin Campos. Alongside Commander Campos are Helga and Zohar which both have torsos that can simulate a female body’s soft tissue, organs, and bones, helping scientists to collect information on the effects of space radiation. The only difference between Helga and Zohar is that one (Zohar) will be wearing a radiation protection vest whereas the other (Helga) will not.
Zero-gravity Indicators: As a nod to its European Space Agency partners, Shaun the Sheep will be onboard as a zero-gravity indicator. Snoopy will ride along as well, harkening back to NASA’s Apollo days. The two plush dolls will be floating in the capsule to indicate when Orion has reached Outer Space.
Legos: four figurines as part of the Lego “Build to Launch” series will be onboard as well. This series is a partnership between NASA and Lego based on STEAM practices to get students excited about space exploration.
Plants: four biological experiments will be conducted by the NASA’s Space Biology Program to study the effects of radiation and how biological systems could adapt and thrive in Outer Space.
Mementos: Artemis 1 will also contain 120 pounds of mementos as part of the Official Flight Kit. This kit will include items such as a pen nib from Charles M. Schulz Museum and Research Center in Santa Rosa, California, a pebble from the shore of the Dead Sea, a small moon rock from Apollo 11, Apollo 8 commemorative medallion, a bolt from the Apollo 11’s F-1 engine, as well as other assorted items that will be handed out as mementos such as flags, patches, and pins.
Artemis 1 CubeSats
Of the 13 CubeSats I wrote about back in February 2018, 10 of them will be making the ride. While not completely full, they will cover a majority of the space allocated for such experiments (Artemis 1 can hold up to 17). These include:
ArgoMoon: Created by the Italian company Argotec and controlled by the Italian Space Agency, ArgoMoon will be operating in close proximity to the ICPS and will take and transmit images of CubeSats as they are released.
BioSentinel: Developed by NASA Ames Research Center, BioSentinel will study the effects of space radiation on biological organisms over long durational missions via its S. cerevisiae (a type of yeast) payload.
CuSP: Also known as CubeSat for Solar Particles, CuSP is managed by the Southwest Research Institute and will act as a space weather station by measuring solar energetic particles and magnetic fields from a heliocentric orbit.
EQUULEUS: Latin for “little horse,” Equuleus also stands for Equilibrium Lunar-Earth Point 6U Spacecraft. Developed by JAXA and University of Tokyo, EQUULEUS will seek to understand the radiation environment around Earth.
LunaH-Map: Designed by Arizona State University, the Lunar Polar Hydrogen Mapper (“LunaH-Map”) will measure hydrogen deposits at the Moon’s south pole.
Lunar IceCube: Created by Morehead State University, this CubeSat will be identifying and observing locations of water-ice deposits on the Moon.
Lunir (formerly SkyFire): Built by Lockheed Martin, Lunir will act as an observer and collect infrared sensor data about the lunar surface through fly-bys.
NEA Scout: Standing for Near-Earth Asteroid Scout, this CubeSat was built by Jet Propulsion Laboratory and Marshall Space Flight Center. NEA Scout will test solar sail as an energy-efficient means of space travel. Shortly after Artemis 1 enters the vicinity of the Moon, the NEA Scout will unfold a sail the size of 925 square feet (86 square meters) that will be supported by four 24-feet (7.3 meters) metallic booms.
OMOTENASHI: a Japanese word for “welcome” or “hospitality”, OMOTENASHI is also an acronym for “Outstanding Moon Exploration Technologies Demonstrated by Nano Semi-Hard Impactor.” This CubeSat was jointly developed by JAXA and University of Tokyo and will attempt to become the world’s smallest moon lander.
Team MILES: Envisioned by Miles Space, this CubeSat will test plasma thrusters as a form of deep space navigation. It will also demonstrate the feasibility of a software-defined radio for communications with Earth.
