This is the first of what AmericaSpace.com hopes are many updates of the Artemis system on a regular basis to bring you, our readers, up to speed on progress of the primary components of the Artemis system, the Orion spacecraft and SLS launcher.
This article is meant to bring readers up-to-speed on the current condition of Orion and SLS as they are prepared for the Artemis 1 mission. Subsequent editions of Artemis Updates will carry news of not only Artemis 1, but of Artemis 2, Artemis 3, Gateway, and others as they come.
A great deal of testing has gone into the Orion and SLS programs to ensure their safety in human spaceflight. More testing is to come. Orion will head to Plum Brook where it will be tested to see how it handles the environment of space. SLS Core Stage’s Green Run test at Stennis Space Center’s B-2 Test Stand is to ensure the Core Stage is safe for launching and performs as needed. After these and some other work is completed, both Orion and SLS will then head to Kennedy Space Center where they will be readied for their Artemis 1 launch.
Why Artemis Updates? Dating myself a bit, I remember watching Neil Armstrong step on the Moon, remember watching astronauts using the first lunar rover on Apollo 15, and the nighttime launch, the only in Apollo history, of Apollo 17. I remember my father pointing to the Moon on the night of July 20, 1969 and telling me that people were now walking on it. And I remember thinking how amazing that was.
Artemis 1 won’t launch for a year or more. And NASA and its partners are still a couple of years away from launching Artemis 2. But when Artemis does fly and, if history is any guide, when humans are again going to the Moon, everything regarding space exploration will change. Because, when we look up at the Moon in the nighttime sky, we won’t see it as a place where people nearly two generations ago once visited but as a place where we are exploring.
So, without further ado…
On July 20th, NASA and Lockheed Martin held a ceremony to announce that the Aretemis 1 Orion spacecraft had been stacked on top of the Orion service module, which was also recently finished.
If you looked at pictures of the Orion stacked upon its European Service Module, you might notice that there were some missing thermal tiles. Also missing was the silver coating that has been shown in pictures of Orion.
The silver coating is a metallic-based thermal control coating. It is the same material covering the heat shield. The coating for the Orion back shield will be bonded to the crew module’s thermal protection system tiles. It has two functions. First, the metallic-based thermal coating will reduce heat loss during phases of flight when Orion is pointed to space and therefore experiencing cold temperatures, and limit the high temperatures the crew module will see when the spacecraft faces the sun. It also will protect against electrical surface charges in space and during re-entry.
According the NASA’s public affairs office, engineers are currently installing the remaining backshell panels on the Orion spacecraft and are expected to finish by the end of August.
Then, the Orion Crew and Service Module, otherwise known as the Orion CSM, will head-over for testing at Plum Brook Station in September.
Space Environment Testing
Plum Brook Station’s Space Power Facility is unique in that large structures, like the Orion CSM stack, can be exposed to the vacuum and temperature environment conditions that would be experienced in low Earth orbit, deep space, and even planetary surface conditions for development or flight qualification. The Space Power Facility, according to NASA, “…houses the world’s largest Space Environment Simulation Chamber (measuring 100 ft in diameter by 122 ft high). Recent facility enhancements have made the SPF home to one of the largest and most powerful reverberant acoustic chambers and the highest capacity mechanical vibration test facility.” In the past, the items tested at Plum Brook Station’s Power Facility have ranged from the Mars rovers to parts of ISS.
After testing at Plum Brook Station is concluded, the Artemis 1 Orion spacecraft will get its metallic-based thermal control system installed on the spacecraft’s backshield. The silver, metallic-based thermal control coating will be bonded to the crew module’s thermal protection system tiles. The coating will reduce heat loss during phases of flight when Orion is pointed to space and therefore experiencing cold temperatures, and will limit the high temperatures the crew module will see when the spacecraft faces the sun. It also will protect against electrical surface charges in space and during re-entry.
Environmental Control and Life-Support System
The Orion Environmental Control and Life-Support System (ECLSS) is moving along in development. Currently, some elements of Orion’s ECLSS are being tested on the ISS and other parts here on the ground.
One part of the Orion ECLSS being tested on ISS is the Amine Swingbed. According to NASA, the Amine Swingbed experiment uses an amine-based chemical combined with the vacuum of space to filter and renew cabin air for breathing. Removing carbon dioxide and moisture from consumed air using this system reduces the demand to supply new air.
Amine Swingbed testing objectives are to, “…assess the prospect for sustainable operations in a flight environment using a water recovery/vacuum regeneration approach. Supporting research objectives are to measure the effectiveness of the CO2 removal system across a wide range of operating conditions.
Orion’s full ECLSS will not be tested on Artemis 1. One reason, according to NASA, is that the absence of a crew means no generation of carbon dioxide, CO2. Without that, one of the primary functions of the Orion ECLSS–removing CO2 from the cabin air–cannot be tested and validated. Still, other parts of the full Orion ECLSS will fly to ensure they can handle the rigors of a trip to the Moon and back.
Orion’s full ECLSS will be fully functional by the time of the first crewed flight, Aretemis 2. Artemis 2 will remain in low-earth orbit for a couple of hours while the crew check and make sure that the ECLSS, along with any other critical system needed for crew safety, is functioning property before initiating the trans-lunar injection (TLI) burn that will put Orion on its path to the Moon.
On September 12, 2018, Orion completed its 24th, and final, parachute test, which were conducted over a ten year period between 2008 and 2018. For those who want a more technical description, the Orion parachute tests were of Orion’s Capsule Parachute Assembly System, or CPAS.
The Orion parachute tests were conducted in cooperation with 418th Flight Test Squadron using the unit’s C–17 Globemaster IIIs and personnel.
Orion’s parachute system employs 11 different parachutes. Testing all of these in different failure modes required 24 tests. The tests objectives included failed drogue deployment, a drogue failure, multiple parachute failures, and a single-out event, in which one parachute doesn’t properly deploy. There were two different test articles used for the parachute tests. Tests needing a higher speed used the Parachute Compartment Drop Test Vehicle (PCDTV), a dart-shaped vehicle. There was also a test vehicle that simulates the Orion spacecraft.
Over the period of ten years of testing, Orion’s Capsule Parachute Assembly System experienced 23 successes and only one failure, which occurred on August 25, 2008. Orion’s ultimate parachute test, EFT–1, occurred on December 4, 2014 when Orion re-entered the atmosphere at around 20,000 mph and landed safely. The final Orion parachute test on September 13, 2018 qualified the Orion parachute system for flights with astronauts.
Launch Abort System
Orion’s Launch Abort System (LAS) passed its Ascent Abort (AA–2) test with flying colors. NASA provided a video of the separation between the launcher and the test vehicle as the abort system pulled it away.
There are two launch critical times for getting the crewed Orion out and quickly. First is on the pad when there isn’t time to get the crew out of Orion and to a safe distance away. This is the pad abort.
On May 6, 2010, the Orion Launch Escape System Pad Abort Test (PA–1) was conducted.. The first test of the Orion LAS was a success and the LAS took the Orion spacecraft to an altitude of 1.75 miles above the test site.
The other critical period occurs when the crew have lifted-off, what is called an ascent abort. For a rocket like SLS that has solid rocket booster boosters, the white columns on both sides of the SLS Core Stage, the need to get the crew far and away is critical. Otherwise, if the boosters are destroyed in an explosion, the spacecraft and its delicate but certainly critical parachutes could be hit by falling, still-burning solid rocket propellant.
A great deal of commotion was made on the Internet in the early days of Constellation, which also had a launcher that used solid rocket motors, about whether NASA could even develop and abort system that would enable the crew spacecraft to escape successfully in such circumstances. Just as NASA was able to land people on the Moon and get the Shuttle to fly, so was NASA successful in developing an abort system that would keep astronauts safe in the event that an ascent abort occurs.
Service Module Propulsion
The Orion service module’s propulsion system was successfully tested on August 5, 2019 at White Sands Test Facility. The test used a qualification version of the Orion service module’s propulsion system.
The August 5th test simulated an abort-to-orbit scenario, in which the Orion CSM separates from SLS second stage, either the Interim Cryogenic Propulsion Stage (ICPS) or the Exploration Upper Stage (EUS).
The Orion service module is built by the European Space Agency. This marks the first time that another space agency is responsible for designing, developing, and constructing a critical element to a U.S. spacecraft.
The Orion service module is 16.5 ft wide by 13 feet long, absent the solar arrays and is constructed on aluminum-lithium alloy. The solar arrays on the Orion service provide electrical power to the module itself and the Orion spacecraft. They are based on the European Space Agency’s ATV’s arrays that originally generated 4.6 kilowatts but have been upgraded to generate 11.2 kilowatts.. When deployed, the Orion service module solar arrays will span about 62 ft (19 m).
The Orion service module provides in-space maneuvering capability, power, and other commodities necessary for life support, including consumables for the astronauts, such as oxygen, nitrogen, and water. Radiators and heat exchangers along the side keep the Orion spacecraft’s occupants and equipment at a comfortable temperature. The Orion service module also serves to provide structural support for the Orion system. The Orion service module weighs almost 8,000 lbs (3,627 kg) and carries almost 19,000 lb (8,6128 kg) of propellant. It has a total delta-V capability of 4,101 ft/s (1,250 m/s). By comparison, the Apollo service module’s total delta-V capability was 9,186 ft/s (2,800 m/s). On the plus-side for the Orion service module, compared to the Apollo service module, it generates approximately twice as much electricity at 11.2 kW vs 6.3 kW, weighs nearly 40% less when fueled at 34,085 lbs (15,461 kg) vs 55,000 lbs (24,520 kg), is 12% smaller at 7,368 ft2 (208.66 m2) vs 8,404 ft2 (238 m2), and supports the environment of a slightly larger habitable volume on the crew module 316 ft2 (8.95 m3) vs 217ft2 (6.17 m3).
The Orion service module uses three different types of engines to get Orion to its destination and to maneuver as needed to align the spacecraft as required for docking and changing its trajectory.
Another advantage of the Orion service module is that, unlike the Apollo service module, it has two means of propulsion to generate the velocity. First, there is the service module’s Orion main engine (OME), an Aerojet-Rocketdyne AJ10–190, that provides 6,002 lbf (26.7kN). The AJ10-190 was developed by Aerojet in 1957 and used in the orbital maneuvering system (OMS) of the Space Shuttle for changing the Shuttle’s orbit. Orion’s service module also has 8 auxiliary Aerojet-Rocketdyne R–4D–11 engines that can generate a total of 880 lbf (3,920 kN), which with additional burn time is sufficient for such events as a trans-earth injection (TEI) burn. Lastly, Orion has 24 reaction control engines in six pods that allow Orion to change its orientation.
On March 21, MSFC posted an update announcing that the Artemis 1 engine section was nearing completion with the majority of outfitting done. The engine section is the bottom of the SLS rocket and is the most complex part of the Core Stage. The Core Stage of SLS consists of, going from top to bottom, the forward skirt, liquid oxygen tank, intertank, liquid hydrogen tank, and the engine section.
On April 16, MSFC posted an update announcing that the boat-tail structure had been added to the engine section intended for the Artemis 1 Core Stage.
The four RS–25’s that will power the Artimis 1 SLS to the Moon arrived at Marshall Space Flight Center’s Michoud Assembly Facility on June 28. The four RS–25’s will be installed later in the summer on the engine section before it is joined to the three sections that have already been joined together. The SLS engine section is expected to be joined sometime in the fall.
On July 2, MSFC announced that the liquid oxygen, intertank, liquid hydrogen, and forward sections of the Core Stage for Artemis–1 were joined. The only remaining section to be joined for the SLS Core Stage to be completed.
Meanwhile, just a few days later on July 10, MSFC announced that the liquid oxygen tank structural test article, the fourth and final structural test article of the SLS Core Stage, had arrived in Huntsville after departing from Michoud on June 26.
On July 18, the liquid oxygen (LOX) tank structural article was loaded into the Test Stand 4697 at Marshall Space Flight Center. There, the LOX tank will be twisted and pressed to structurally simulate launch conditions. With the testing of the liquid hydrogen structural article begun on January 15, 2019 and now completed, and the Feb. 2, 2018 conclusion of testing the SLS engine section, structural testing of the LOX tank article will conclude structural testing of the SLS Core Stage.
The Green Run, as announced by NASA Administrator Bridenstine, is on! According to NASA’s Public Affairs Office, the completed SLS Core Stage is expected to be shipped to Stennis Space Center by year-end. Once at Stennis, the SLS Core Stage will be loaded on the center’s B–2 test stand. The B–2 test stand has a storied history, being constructed to test the Saturn V first stage, or S–1C. Refurbishment for use in the SLS Core Stage Green Run test was completed in 2016. The SLS Core Stage Green Run test gets its name because in earlier testing dedicated non-flight, or green, hardware was used in testing. The SLS Core Stage Green Run test is the first time that actual flight hardware will be used.
The Green Run test includes fueling and pressurizing the Core Stage and culminates with firing up all four RS–25 engines to demonstrate that the engines, tanks, fuel lines, valves, pressurization system, and software can all perform together during launch. The Green Run is expected to last 6 months. Afterwards, the SLS Core Stage will be cleaned-up and then shipped to Kennedy Space Center, where it will be stacked in the Vehicle Assembly Building (VAB) with the rest of the Artemis 1 hardware.
Solid Rocket Booster
The SLS Solid Rocket Booster (SRB) derives from the Shuttle Solid Rocket Booster (SRB) and are officially named the redesigned solid rocket motor V (RSRMV). Although derived from the Shuttle SRB, there are significant differences with the SLS version. The most noticeable difference is an additional section added onto the 4-segment Shuttle motor. But other changes were made as well such as new, more environmentally-friendly insulation instead of asbestos, software, and new mechanical systems. With so many changes, qualifying the redesigned solid boosters for human spaceflight would be necessary.
A total of five static fire tests were undertaken to verify the design of the Solid Rocket Booster. All static fire tests were conducted at T-97 test stand at Northrop Grumman’s Orbital-ATK Promontory, Utah facility.
The first Demonstration Motor-1, or DM-1, was tested on September 10, 2009. This was the first full-scale, full-duration test firing of the first stage motor for what was then called the Ares I rocket. DM-1’s success led to the Ares 1-X test flight on October 26, 2009 at Kennedy Space Center, which was itself a success. The Demonstration Motor-2 static fire test (DM-2) in 2010 was a full-duration test of how the SRB operated in cold temperatures of 39°F (4°C). The Demonstration Motor-3 test (DM-3) on September 8, 2011 tested how the SRB handled high temperatures of around 102°F (39°C). Success in the demonstration tests meant that SRB testing could proceed to qualification test.
On June 17, 2011, the day NASA Administrator Charlie Bolden announced the approval of the design for the Space Launch System, it was also announced that redesigned solid rocket motor would be used as the booster on the SLS Block 1 launchers.
After the successful demonstration test of the motors, and following their designation as the boosters for the SLS, the next step in the development of the SLS RSRMV were qualification tests, of which there would be two. Qualification Motor-1 test (QM-1) on December 23, 2014 tested the SRB at 102°F (39°C). The final test, Qualification Motor-2 (QM-2), occurred on July 14, 2016 at Northrop Grumman Orbital-ATK’s T-97 test stand at the Promontory, Utah facility. The goal of QM-1 was to test and verify the motor’s performance in cold temperatures, 40°C (4.4°C).
The SLS solid rocket booster is the largest, most powerful solid rocket motor ever built for flight. It is 12 ft (3.66 m) wide and 177 ft (53.95 m) long. Each booster has a dry weight of 100,000 lbs (45,359 kg), propellant mass of 1,500,000 lbs (680,388 kg), and a total mass of 1,600,000 lbs (725,747 kg) and produces 3.6 Mlbf (16,000 kN) of thrust. Together, both boosters produce 7.2 Mlbf (32,000 kN) of thrust, or over 85% of the total thrust of 8.4 Mlbf (37,365 kN) that SLS produces at lift-off. Compared with the Saturn V’s 7.5 million lbf, this might be why it’s called the most powerful rocket ever created.
Orion and SLS are progressing towards the first launch of the Artemis program, Artemis 1. In testing, both Orion and SLS have met or exceeded their needed performance. But much of that goes unreported to the public. We hope to change that.
Artemis has its critics who are quick to point-out its perceived short-comings. For one, they claim that the Orion and SLS programs are over-budget–they are not, if you know what Congress agreed to when creating the Orion and SLS programs. They do however correctly point-out that Artemis is behind schedule. NASA and its contractors can take cold comfort that every single human spaceflight effort–Gemini may be the exception–has been behind schedule. One need only look at Mercury, Shuttle, Virgin Galactic, and Commercial Crew to verify that. Ensuring crew safety in spaceflight inherently means running-up against new challenges that cannot be easily foreseen. But throughout its history, NASA, its contractors, its partners, and others have conquered those challenges and answered the call to go to the final frontier. One thing is certain; when Artemis does begin flying, it will push the boundaries of human space exploration like no program before.
And we will work to bring to you updates as frequently as we can so you can see Artemis progress towards reigniting human exploration in space.
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