Category: Space Sunday

On Friday, December 20th, 2019, NASA and Boeing, together with launch partner United Launch Alliance (ULA), attempted to undertake the first flight of the Boeing CST-100 Starliner commercial crew transportation system to the International Space Station (ISS).

I say “attempted” because while the first part of the mission went precisely to plan and the Starliner successfully reached orbit, a software issue left it unable to reach the ISS. However, while this prevented a core mission objective from being met – that of rendezvousing and docking with the ISS – it did not leave the mission a failure: the ascent to orbit was successful, with a lot of data gathered on the vehicle’s performance, and further data could be gathered while on-orbit and during the vehicle’s return to Earth – also a critical part of the test.

The vehicle was uncrewed for this test flight, but is carrying a range of cargo – including Christmas gifts for the ISS crew; tree seeds that will be planted on Earth after the mission to mark it; a mannequin fitted with a host of sensors to measure the stress placed on a human body during the flight to orbit (the mannequin is called “Rosie the Rocketeer” in reflection of “Rosie the Riveter”, the iconic role model for U.S. women working in factories and on production lines in WWII, and a Snoopy soft toy “zero gee indicator” – Snoopy is the mascot for NASA’s Artemis programme to return humans to the Moon.

Things started off well enough: following a near-perfect count down, the core booster of the Atlas V and its two strap-on  solid rocket motors ignited precisely on time at 11:36:43 UT (06:36:43EST) on the launch pad of Space Launch Complex 41 at Cape Canaveral Air Force Station, and the vehicle lifted off smoothly into the still-dark early morning sky.

Due to the need to keep the vehicle within a 3.5 G limit during ascent, the Atlas V rose into a “flat” trajectory during its climb, the two solid rocket boosters being  jettisoned some 2 minutes into the flight, the core stage motors continuing to burn for almost three more minutes before BECO – Booster Engine Cut-Off – was called. Shortly after, the core stage of the Atlas V separated from the Centaur upper stage, allowing it to fire its twin RL-10A motors – marking the first time a twin-engined Centaur had been used with the Atlas V booster. Again, the additional power provided by the additional motor was required to push Starliner toward orbit, running for seven minutes in the process.

It was after the Starliner has separated from the Centaur upper stage that the major problem occurred. At this point, the vehicle was supposed to orient itself and then fire the main engine on the service module to push itself into an initial orbit that would allow it to complete further engine burns to both raise its orbit and circularise it, allowing the Starliner to catch-up and rendezvous with the ISS.

However, that initial burn failed to occur on time. Instead the vehicle continued to fire its attitude control thrusters while ignoring commands from Earth to fire the the service module’s motor. Some seven minutes passed before the engine was ignited, allowing Starliner to achieve its initial orbit – but by that time its was “off course” in relation to where it needed to be in order to catch up with the ISS, and had used too much attitude control system fuel to be able to make necessary course corrections and achieve any form of rendezvous with the ISS.

The Boeing Starliner space vehicle experienced an off-nominal insertion. The spacecraft currently is in a safe and stable configuration. Flight controllers have completed a successful initial burn and are assessing next steps. Boeing and NASA are working together to review options for the test and mission opportunities available while the Starliner remains in orbit.

– Kelly Kaplan, Boeing’s spokesperson, after the planned automated engine burn failed

According to initial investigations, it is believed that the mission clock aboard Starliner overseeing all of the vehicle’s automated flight operations – including triggering the engine burn – had incorrect data, causing it to believe the service motor had fired, and thus triggering the use of the attitude control system.  While the issue left Starliner unable to reach the ISS, mission controllers were able to order the vehicle to complete two additional engine burns to put it into a near-circular 250km high orbit, where a range of tests on the vehicle have been made, and from which it could complete its planned EDL – entry, descent and landing.

A couple of important points to highlight here is that had the vehicle been carrying a crew, they would not have been in any danger – in fact, they would likely have been able to correct the initial burn failure, allowing the rendezvous with the ISS to take place.

With the issue understood – if not the cause known – the decision was taken to complete the planned orbital tests and then bring the Starliner back to Earth  and a landing at the White Sands Missile Range, New Mexico on Sunday, December 22nd. These orbital test included testing the navigation systems and the vehicle’s flight handling, and communications (including establishing a link with the ISS).

Landing commenced with Starliner turning itself around and using the service module’s motor in a de-orbit burn. This took place at 12:23 UT (06:23 CST at the White Sands landing ground) on December 22nd, slowing the vehicle sufficiently for it to start a decent into the denser part of the Earth’s atmosphere. Three minutes after this, the service module was detached and left to burn-up in the upper atmosphere.

The capsule, protected by a double heat shield system – referred to as the forward heat shield (protecting the upper part of the vehicle: the airlock and the landing system parachutes) and the base heat shield (at the base of the capsule and designed to protect it from the full heat of atmospheric entry) and covered in a thermal protection system – reached “entry interface” some 20 minutes later. This is the point where the atmosphere becomes dense enough to generate friction around the vehicle, both heating up and slowing the vehicle down. At this point, Starliner was some 15 minutes away from landing.

Continue reading “Space Sunday: Starliner’s first orbital flight” →

A time-lapse video of the SpaceX CRS-19 cargo Dragon being captured by the Canadarm-2 of the International Space Station (ISS)

The past week has seen two resupply missions launched to the International Space Station (ISS), which between them will deliver 4.6 tonnes of supplies and equipment to the station, including some special visitors.

The first mission, CRS-19, featuring a SpaceX Dragon and Falcon 9 launch vehicle, lifted-off from Cape Canaveral Air Force Station (adjacent to the Kennedy Space Centre) on Thursday, December 5th, after being delayed 25 hours due to high winds over the launch site. It rendezvoused with the ISS at 10:05 GMT on Sunday, December 8th. The second mission features a Russian Progress resupply vehicle, which lifted off from the Baikonur Cosmodrome in Kazakhstan at 09:34 GMT on Friday, December 6th, and is due to dock at the ISS on Monday, December 9th, carrying a mix of food, fuel and supplies.

However, it is the Dragon vehicle that has captured most attention, due to its cargo. As well as carrying the traditional Christmas goodies for the ISS crew, CRS-19 carried 40 passengers in the form of mice and elements of the station’s increasing use of robots.

The mice will spend a month aboard the ISS as a part of research into two of the most debilitating effects of spending extended periods in micro-gravity environments such as orbiting the Earth or something like a 6-month flight to Mars: muscle and bone mass loss.

Several of the mice have been dubbed “mighty mice” on account of their being genetically engineered by scientists at the Jackson Laboratory for Genomic Medicine (JAX-GM) in Maine, USA. Specifically, they have been engineered to inhibit myostatin, a molecule that occurs in mammals that regulates muscle growth (discovered in 1997 by Dr. Se-Jin Lee), allowing them to develop increased muscle mass compared to ordinary mice.

The idea is that by inhibiting the myostatin, the mice will be able to maintain both muscle mass and limit bone calcium loss whilst at the station, the lack of myostatin allowing them to continue to convert protein into muscle mass despite the mice being less active on the station than the would be on Earth.

They will spend their time on the ISS with a group of mice that have not had their myostatin blocked, and with two similar group sof enhanced  / non-enhanced mice on Earth, to determine the overall impact of the lack of myostatin in the production / maintenance of muscle  bone mass in micro-gravity compared to how myostatin might contribute to muscle / bone mass loss when allowed to function normally.

As well as helping determine what medical / genetic assistance can be given to humans on long duration, low-gravity space missions (possibly alleviating the need for up to 4 hours a day to be spent in exercise to counter muscle / bone mass loss), it is hoped that controlling / inhibiting myostatin’s function could be used to help treat patients recovering from hip fracture surgery, or those in intensive care where muscle growth could be a major factor in their recovery, and to assist elderly people suffering from muscle loss or osteoporosis.

CIMON Returns to the ISS

In addition to the mighty mice, the CRS-19 mission also delivered CIMON-2 (“Simon-2”), an updated versions of a robot assistant for ISS crews. Developed by Germany’s DLR CIMON (Crew Interactive Mobile CompaniON) is a medicine-sized robot that can float around the ISS using 14 small fans boasting a combination of IBM Watson AI, cloud connectivity, and neural network training. It was first flown aboard the ISS in 2017 / 2018, and is capable of assisting with routine tasks and research projects, displaying instructions on its forward screen, and recording images. It can also recognise, learn from, and bond with crew members through natural language; offer creative solutions to tricky challenges; and even serve as a security guard, noticing potential problems before they become dangerous.

Unfortunately, the first outing for CIMON didn’t entirely go according to plan, in an outing with ESA astronaut Alexander Gerst, things started out well enough, with CIMON helping Gerst complete some test tasks, but problems arose when Gerst asked it to play his favourite music. Selecting Man Machine by Kraftwerk, CIMON continued to play the music while accepting other tasks, and when Gerst ordered, “Cancel music” the robot to replied, “I love music you can dance to! Alright, favourite hits incoming.”

While CIMON could still comprehend other commands, it appeared to become confused and not a little stroppy as Gerst communicated with those monitoring the test. “Be nice, please,” it requested at one point, followed a little later by, “Don’t you like it here with me?” and “Don’t be so mean.”

The improved CIMON-2 comes with more sensitive microphones that will hopefully allow it to hear better and not confuse commands, and a more robust AI system to allow it to better understand when it is being addressed and when an astronaut might be talking to someone else. This improved AI system includes IBM Watson Tone Analyser technology, which uses linguistic analysis to detect emotion in the tone of a conversation and respond to it – which given CIMON’s own moodiness noted above, could be interesting!

CIMON-2 is expected to spend up to three years aboard the ISS. As well as serving as a test bed for easing the stress of living and working in limited environments like the ISS and in developing greater understanding of how robots and AI can function to support crews on long duration missions, CIMON-2 is also potentially a stepping stone for developing the necessary trust human crews require to make the routine use of such systems  – which can record, process and store human activities, interactions and moods, raising concerns of privacy and data security – acceptable to crew.

Dextre, RELL and and the “Robot Hotel”

Robots are an important part of future human space activities, and over the years, a number of systems have been employed or tested aboard the ISS, for working both inside and outside the station. The most obvious of these is the Canadarm-2 remote manipulator system used outside of the ISS, while inside the ISS there have been robot system like CIMON and FYODOR (see: Space Sunday: Lunar landers, and robots in space).

Continue reading “Space Sunday: on the ISS – mighty mice and robots” →

Fifty years ago, on Friday, November 14th, 1969, the second Apollo Saturn V intended to place humans on the Moon lifted off from Launch Complex 39A at Kennedy Space Centre. Aboard it were mission commander Charles “Pete” Conrad Jr, Command Module Pilot Richard F. Gordon Jr, and Lunar Module Pilot Alan L. Bean.

Coming four months after the launch of Apollo 11, the Apollo 12 mission was intended to extend lunar surface operations, albeit modestly. Armstrong and Aldrin spent a total of 21 hours and 37 minutes on the Moon and completed a single surface EVA, Conrad and Bean would spend 31 hours and 29 minutes on the lunar surface, performing two EVAs in the process. However, it became the mission that almost had to be aborted thanks to a pair of incidents that occurred in the first minute after lift-off.

The crew for the flight were of mixed experience: Conrad was making his third trip into space, having flown the Gemini 5 and Gemini 11 missions; Gordon was making his second flight, having partnered with Conrad during Gemini 11; Bean was on his first flight into space. Conrad had joined NASA as part of the second astronaut intake group that included Neil Armstrong, while Gordon and Bean were both part of the third intake alongside of Edwin Aldrin.

Conrad joined NASA from the US Navy, where he was regarded as an outstanding carrier-based fighter pilot and first-class test pilot and flight instructor. He was regarded as one of the best pilots in his group, and was among the first of his group to be assigned a Gemini mission, flying alongside Mercury veteran, Gordon Cooper, the second American to orbit the Earth. He was also one of the most diminutive of the astronauts, standing just 5ft 6.5 inches tall. However, he made up for his small stature by being at times outspoken and a little irreverent (he facetiously referred to the Gemini 5 capsule as a “flying garbage can” during the then record-setting mission of almost 8 days in orbit, on account of the cramped size of the vehicle). While these qualities rankled some in NASA’s management, his forthrightness allowed him to become central to testing many spacecraft systems essential to the Apollo programme. These tests included the Gemini 11 mission with Gordon, and which remains the highest ever Earth orbital mission completed to date, with an apogee of 1,369 km (851 mi).

Conrad has a further distinction: under NASA’s original plans, he was selected to command the back-up crew for Apollo 8, the first test flight of the Lunar Module in Earth orbit. Under the standing protocol of back-up crews moving to a “prime” mission slot three missions later, he was in line to command Apollo 11. However, delays in getting the Lunar Module ready for flight meant that Apollo 8 and Apollo 9 were swapped, shunting his command slot to Apollo 12.

Both Gordon and Bean also came to NASA from the US Navy, where they had also served as fighter pilots before transitioning to test pilots. Both also served with Conrad during their military careers: Gordon with Conrad aboard the aircraft carrier USS Ranger, where the two shared a cabin and had become good friends, while Bean was trained by Conrad when becoming a test pilot, the two also forming a friendship in the process.

Apollo 12 launched from Cape Kennedy into a cloudy, rain-swept sky. 36.5 seconds into the flight, lightning struck the top of the vehicle and travelled through it and its ionised exhaust plume to strike the launch gantry it had just cleared. Protective circuits on the fuel cells in the service module (SM) took them off-line, along with much of the Command Module’s flight systems.

15.5 seconds later lightning again struck, disabling the attitude indicator and garbling telemetry being received by Mission Control. However, neither strike affected the Saturn V rocket’s instrument unit, allowing the vehicle to continue to climb towards orbit as planned.

The loss of the fuel cells placed the CSM on battery power, but this wasn’t up to the task of providing all the power necessary to power the Command Module’s instruments for the entire mission. Nor could the fuel cells be brought back on-line.

Flight Director Gerry Griffin was considering calling for an orbital abort, despite fears the lightning strikes may have affected the Command Module’s parachute deployment pyrotechnics, when John Aaron, the Electrical, Environmental and Consumables Manager (EECOM) realised he’s seen a similar pattern of telemetry disruption during an equipment test, when a power supply unexpectedly failed.

“Flight, EECOM. Try SCE to Aux,” he stated over the radio, recalling an obscure back-up power supply switch-over.

His call went unrecognised by Griffin, the CapCom, astronaut Gerald Carr, and Conrad on Apollo 12. However, rookie Alan Bean remembered the SCE switch from a training incident a year earlier during a rare simulation of such a failure, and flicked it over. The move brought the fuel cells back to power, and both Aaron and Bean were credited with saving the mission.

After the excitement of launch, the flight settled into “routine”, with Apollo 12 reaching the Moon late on November 17th, 1969. An initial engine burn put the combined Command and Service Module (CSM) Yankee Clipper and Lunar Module (LM) Intrepid into and elliptical orbit of 110.4 x 312 km (69 x 195 mi). On November 18th, this was adjusted to 99.2 x 121.6 km (62 x 76 mi), and on November 19th, Conrad and Bean entered to the Lunar Module ready for their descent and landing.

This began after Intrepid had separated from Yankee Clipper, with an engine burn on the far side of the Moon, out of contact with Earth. The landing site was set within a region of Oceanus Procellarum, the Sea of Storms that had been given the official name of Mare Cognitum (Known Sea) on account of it having been visited by three automated probes: Russia’s Luna 5 and America’s Surveyor 3, and Ranger 7. The aim was to put Intrepid down in a precisely-denoted area within walking distance of Surveyor 3, and which Conrad had dubbed “Pete’s Parking Lot”.

Continue reading “Space Sunday: Apollo 12, 50 years on” →