On August 29th, NASA made a significant decision to bring its astronauts back to Earth aboard a SpaceX Crew Dragon spacecraft rather than Boeing’s Starliner. This follows a rocky start to Boeing’s first Crew Flight Test (CFT) spaceflight mission, which launched on June 5th with two NASA astronauts bound for the ISS on an 8-day mission. However, things haven’t gone as planned. Starliner will now return to Earth uncrewed on September 6th, marking a substantial commercial and reputational setback for Boeing. Should a catastrophic failure occur during reentry or landing, it could spell the end of Boeing’s Starliner program altogether.
Boeing has provided abundant assurance that Starliner is safe for a crewed return. After all, they have already returned Starliner from LEO to a safe, soft landing in New Mexico twice, once in 2019 and again in 2022. Why does NASA not feel assured?
There are four critical contributory factors. Perhaps the most visceral is NASA’s 2003 experience with the loss of a crew of seven during the ill-fated space shuttle Columbia’s return to Earth. If there are fatalities, it will be seen as NASA’s failure, not Boeing’s. Secondly, this NASA-Boeing commercial contract is a fixed-price one. Boeing, not NASA, will have to pick up the additional cost necessary to certify Starliner as operational. Thirdly, NASA has an alternative option, something that was not available in 2003: SpaceX. Why should NASA take the risk if it doesn’t have to? Lastly, with a comprehensive understanding of all the intricate and interconnected technical details, NASA knows more than we do and feels it has no other choice.
Multiple Failures
NASA and Boeing have acknowledged “multiple failures,” which is not unusual in a test flight. The previous Starliner flights (in 2019 and 2022) were not without failures. The two main problems with Starliner in this CFT have made it to the public domain: five helium leaks and thruster malfunctions. The helium leaks, known about before launch, were not deemed significant. Starliner arrived and docked successfully with the ISS on June 6th. Boeing engineers assessed the leak rates and concluded that the remaining helium could support 70 hours of free flight, but only seven were required. Starliner had sufficient margin for a safe return trip from the ISS.
Helium pressures the 20 Reaction Control Systems (RCS) for fine attitude control and 28 more powerful Orbital Manoeuvring and Attitude Control (OMAC) thrusters. All 48 are located in 4 units (each with 5 RCS and 7 OMAC) known as doghouses on the Service Module. The thruster malfunctions, specifically understanding their root causes, are the primary concern. When the OMAC thrusters are activated, they generate much more heat than expected. In the confined space of the doghouses, that heat is absorbed by the Teflon seals in the RCS, causing the seals to bulge and potentially disintegrate. The resulting debris can block the oxidizer supply to the RCS, resulting in lower thrust. Boeing engineers have replicated some of these symptoms in their ground tests. The uncertainty associated with repeated bulging of the seals during reentry appears to have motivated NASA to throw in the towel with Starliner. Starliner will return uncrewed on September 6th, and NASA astronauts Barry Wilmore and Suni Williams will return with SpaceX in February 2025.
This is perhaps NASA’s most consequential decision. NASA wanted two independent routes for crewed flights to LEO from the outset. Since the Space Shuttle was retired, NASA has spent about $11 billion on its replacement—the Commercial Crew Development Contracts. The lion’s share is almost equally split (SpaceX $5.5 billion and Boeing $5.1 billion). This includes 6 Boeing missions to the ISS and 14 SpaceX crewed missions to the ISS. SpaceX has completed 13 crewed return missions to the ISS, and Boeing has yet to complete its first.
Corporate Decline?
Following NASA’s decision, SpaceX will exploit Boeing’s uncomfortable reputational and commercial predicament. NASA did not take it lightly, and it was probably not informed solely by the quality of Boeing’s work on Starliner but by a broader recognition of Boeing’s performance over decades.
The first stage of the mighty Saturn V, which powered eight crewed Apollo missions to the Moon, was developed by Boeing engineers. From the same decade, the 1960s, Boeing has been a byword for safe aviation. The Boeing 737 and the 747 Jumbo have impressive safety records, not just in the US but globally. Perhaps the 1997 merger between Boeing and McDonnell Douglas shifted the company culture from safety and quality to profit and dividends. Confidence in the integrity of Boeing’s engineering declined further, with two fatal crashes in 2018 and 2019 of its new 737 Max aircraft, resulting in the loss of 346 lives.
Boeing’s difficulties are not restricted to aviation or Starliner. In early August, NASA’s Office of Inspector General published a report on the status of the Space Launch System (SLS) Block 1B. Boeing is the prime contractor for the SLS Exploration Upper Stage (EUS), where the cost has grown from $962 million to over $2 billion. The report found that Boeing’s quality assurance program is not compliant with NASA’s Quality Management System standard AS9100. Between September 2021 and September 2023, Boeing received 71 Corrective Action Requests and is now facing the prospect of financial penalties for non-compliance with quality control standards.
Critical Reentry
Despite media reports, NASA’s astronauts are not stuck, stranded, or abandoned. As the mission designation, Crew Flight Test, indicates, this is a test flight. Barry Wilmore and Suni Williams are space shuttle veterans. They are in no immediate danger and probably welcome their extended stay in space. It is very rare for a spacecraft that took people to space to return empty. In March 2023, the Soyuz MS-22 spacecraft returned to Earth uncrewed following safety concerns with an external cooling radiator on its service module.
The Service Module does not survive reentry, so Boeing engineers will not be able to investigate it further after it has returned to Earth. Firing all 28 thrusters during the uncrewed return will be essential for Boeing to collect additional data to inform the necessary modifications. That step may also result in unpredictable and potentially catastrophic failure. That unlikely event could vindicate NASA’s decision and mark the demise of the Starliner program.
I think Boeing engineers will succeed in returning the CFT safely to Earth. On the current schedule, on September 6th, Starliner will undock from the ISS at 6:04 and land on the 7th at 12:03 EDT. Space is hard for Boeing right now, but it will have moved on in a few years. These profound difficulties will be interesting footnotes in Boeing’s developmental history.
Chandrayaan-3: India’s Foothold on the Moon
A Political Imperative
On Friday, 23rd August 2023, moments after confirming the successful soft landing of the Vikram lander with the words “we are on the Moon,” ISRO Chairman Somnath invited Indian Prime Minister Modi to speak. Unlike September 2019, during the unsuccessful Chandrayaan-2 lander mission, Modi was not in Bangalore but in South Africa, attending a BRICS meeting. This mission, a product of national political and financial commitment, attracted international acclaim.
With one eye on the vast national and international audience and the other on the upcoming general election in 2024, the Prime Minister spoke for ten minutes. Politics and politicians play a more critical role in facilitating space missions than the scientists and engineers who realise them. When Apollo 11 astronauts Neil Armstrong and Buzz Aldrin took humanity’s first steps on another world, they received a live telephone call from President Nixon from the White House, which they shared live on TV around the world. Whereas Apollo 11’s success was a goal set in response to the USSR’s spectacular success in placing the first human in Earth orbit on 12th April 1961, India’s Chandrayaan-3 success was in response to its regional competitor, China.
India’s first official announcement to go to the Moon came on 15th August 2003. This announcement was not driven by the urge for scientific exploration but more likely a response to China’s announcement in January of the same year that they would launch a mission to the Moon. Ultimately, India reached the Moon on 8th November 2008 with Chandrayaan-1, a year after Chang’e 1, the first Chinese lunar mission, arrived in lunar orbit on 5th November 2007. Reflecting the geopolitical rivalry of the USA and USSR during the Cold War, India and China continue that silent rivalry today. China has achieved several remarkable successes in space (human spaceflight, landing a rover on Mars, lunar sample return, and now a continuously inhabited space station). With its larger economy and centralised political structure, China has rapidly grown in its space capabilities, now second only to the USA. The gap between India and China is exemplified by one metric: In 2023, ISRO missed breaking its all-time high of seven launches in one year, whereas China achieved a new high of 67.
It is not only international politics that influence how ISRO operates but national politics as well. The ISRO website uses English and Hindi, but individual centres may prefer a local language. For over a decade, India has had an Official Language Implementation Committee promoting using Hindi as an official language across all ISRO centres. This remains a challenge given that surprisingly large populations across India do not speak Hindi. As in medicine, science, and information technology, English is the world’s default language for the space industry.
The success of Chandrayaan-3 has demonstrated ISRO’s technological competence and is likely to secure the two key ingredients to accelerate India’s space program: increased political and financial commitment. Propelled by Chandrayaan-3’s success and motivated by China’s ongoing achievements, India will pursue more ambitious space missions. India’s delayed human spaceflight program is on target for the first flight of an Indian astronaut on board an Indian launch vehicle from India by 2025. Motivated by this success, India will likely announce missions for a lunar sample return, Martian rover, Venus orbiter, and exoplanet hunter, and develop more powerful and reusable launch vehicles.
Lessons from Chandraayan-2
Chandrayaan-2, weighing almost 4 tons, was launched in July 2019 using a new LVM-3 rocket. It arrived in lunar orbit on 20th August, and the lander separated on 2nd September; however, the landing attempt was unsuccessful. The Chandrayaan-2 orbiter is now five years into its planned 7.5-year operational life, returning the highest resolution images of the lunar surface among the seven operational spacecraft currently in lunar orbit. Images for identifying potential landing sites for the Chandrayaan-3 lander came from the Chandrayaan-2 orbiter. Whilst the Chandrayaan-3 lander communicated directly with Earth during descent and on the surface, the Chandrayaan-2 orbiter served as a redundant communication relay for the lander in 2019. The Chandrayaan-3 orbiter, which ISRO refers to as the Propulsion Module, did not have this relay capability.
The Chandrayaan-2 Failure Analysis Committee (FAC) findings highlighted concerns with the inadequacy of data on the spacecraft’s attitude, altitude, and velocities during the powered descent. The report pointed to the need for (i) a larger landing target and finer engine thrust controls and (ii) more precise and frequent data on horizontal and vertical velocities, as well as altitude during the powered descent. Chandrayaan-3 would need to know, with higher precision, its location, altitude, and attitude at all times during the powered descent phase. Recommendations included more efficient hazard-avoiding algorithms with built-in redundancy, especially during the fine braking, hovering, and final touchdown phases. As a result, Chandrayaan-3 became ISRO’s spacecraft with the most built-in redundancy to date. The additional instruments which facilitated these recommendations included laser and radio frequency-based altimeters, laser Doppler and horizontal camera velocimeters, laser gyro-based inertial referencing, and accelerometers. The fifth non-throttleable engine in Chandrayaan-2 was removed altogether, reducing the dust kicked up at landing. The four throttleable engines were reconfigured to allow changes of thrust in increments of 10% rather than 20%. The attitude correction rate was also enhanced from 10°/s for Chandrayaan-2 to 25°/s for Chandrayaan-3.
With so many modifications, ISRO planned and conducted a series of experiments to test the new configuration. An Indian Air Force helicopter supported an Integrated Cold Test where navigation sensors were flown over an ISRO-created lunar landscape in the Chitradurga district, about 300 km northwest of Bangalore. India’s vast launch centre at Sriharikota was used to conduct an Integrated Hot Test, which involved the lander hanging from a crane to test propulsion, navigation, guidance, and the updated flight software. Despite the numerous simulations and physical testing, the space environment, which includes near vacuum, extreme variations in temperature, and one-sixth gravity in the vicinity of the Moon, cannot be duplicated on Earth.
The lander mass was increased to 1,726 kg (from Chandrayaan-2 lander’s 1,471 kg), most of this was in fuel. The additional fuel would allow for longer hover periods to avoid hazards and identify the most optimal landing target. The landing zone also increased from 500 m by 500 m to 2,400 m by 4,000 m. In February 2019, a landing simulation for the Chandrayaan-2 lander resulted in some damage to the lander’s legs. As an additional contingency, Chandrayaan-3 lander legs were reinforced to support the eventuality of a harder landing, which also increased the lander’s mass. A series of lander drop tests were conducted to ensure a safe landing with a vertical speed of up to 2 m/s, a horizontal speed of up to 5 m/s, and landing on a slope of up to 12 degrees. Other subtle changes included increasing battery capacity, data transmission capacity during powered descent, solar cells, and enhancing reaction wheels.
ISRO chose to meet the commercial request from OneWeb to launch its satellite in October 2022 and again in March 2023. In the absence of this delay, Chandrayaan-3 would have been launched much earlier. With multiple hardware and software enhancements and rigorous testing, almost three years later, ISRO, with greater confidence, launched Chandrayaan-3 on 14th July 2023.
What Next
Lunar landers and rovers from the USA, USSR, and China survived the lunar night using a Radioisotope Thermoelectric Generator (RTG). The first use of an RTG in space was an experimental navigation satellite placed into Earth orbit by the US Navy in 1961. It used 96 g of Plutonium 238 to demonstrate an alternative, independent power supply. The heat was converted to electricity to power onboard instruments and used for temperature control while the spacecraft was in the Earth’s shadow. During the early 1960s, solar cells had very low efficiency compared to today. International sanctions following India’s first nuclear test in 1974 restricted India’s access to nuclear materials, preventing it from developing RTG technology. Since 2016, India has become a member of the Missile Technology Control Regime, and in 2023 signed the US-led Artemis Accords. Free of the restrictions of the past, India is now developing nuclear power sources for use in space.
As expected, neither Chandrayaan-3’s lander nor the rover survived the ultra-low temperature of a lunar night. The mission ended less than two weeks after the touchdown. Prior to launch, the rover was tested to a temperature of -145°C, but since it could only communicate with Earth via the lander, it is impossible to say if it survived the lunar night.
India is now working on both a Radioisotope Thermoelectric Generator (RTG) and a technologically simpler device based on a radioisotope source, a Radioisotope Heater Unit (RHU). The RHUs are incapable of providing electricity—only heat. They are used in environments other than space, including geographically remote locations on Earth (oceans, polar regions, unattended lighthouses, autonomous vehicles). ISRO tested its first RHU in the Chandrayaan-3 Propulsion Module, and RTG technology will likely follow. ISRO is expected to test a 5W RHU in a Technology Demonstrator Satellite.
ISRO has not formally announced the next mission to the Moon, but it is probably a sample return. This is not only because it follows in the footsteps of the Chinese Lunar Sample Return but also because for any space agency to grow, it must evolve. The scientists and engineers at ISRO will have enjoyed the success of the Chandrayaan-3 lander but will need to add to their experience by taking on the technologically ambitious challenge of sample return. Currently, the early design phase is likely to involve two launches. The first launch will include a Propulsion Module to get to the Moon, a Descent Module for the lunar landing, and an Ascent Module to take the samples back up to lunar orbit. The second launch vehicle, probably a GSLV Mk-2, will carry another propulsion module to the Moon and back and a Transfer Module that will dock with the ascent module in lunar orbit, transfer the samples, and return to Earth for re-entry. Where on Earth it will land has not been finalised. Perhaps mainland India, the Indian Ocean, or the Australian Outback.
Long-term and sustainable exploration and exploitation of the Moon have become a geopolitical target for many nations in this and the coming decade. Just as in the 17th century, European countries competed with each other to acquire new lands in Africa, Asia, and the Americas, and in Antarctica in the 20th century, so today, countries worried about being left behind are committing political and financial resources to establish a foothold on the Moon. A base on the Moon will also be a stepping stone to exploring Mars and beyond. The two countries with concrete plans for sending humans to the Moon are China and the USA. India has stated that it wants to send people to the Moon. It has joined the US-led Artemis Accords instead of partnering with the Chinese and Russian program called the International Lunar Research Programme. Apart from the potential for an Indian astronaut to visit the International Space Station, these new partnerships might provide India with access to the technologies it needs to accelerate and fulfil its growing lunar ambitions.
Episode 116: Exploring Cosmic Events with Professor Rene Breton at Jodrell Bank Centre for Astrophysics
Some of the most energetic events in the cosmos are associated with the products left after a star’s violent end. These products are always smaller and denser: a white dwarf (the size of a planet), a Neutron star (the size of a city), or a Black Hole (an object without a size). The bigger the initial mass of a star, the sooner and more energetic its end will be. Our Sun is not all that massive; it will end up as a white dwarf in and out 4.5 billion years from now.
Professor Rene Breton, originally from Quebec, has been working at the Jodrell Bank Centre for Astrophysics for over a decade. We discuss only a small part of his current research, including how Pulsars may one day be used as a GPS for interstellar travel. Other topics include
- Why and how he ended up in Manchester
- His first impressions of Manchester and comparisons with Quebec in Canada
- The key role of a high-school teacher, Mr. Gaudreault, setting him on his career in science
- Stellar evolution – how stars are born and the process by which they end up as white dwarfs, neutron stars and black holes
- Event Horizon Telescope – imaging the black hole in the centre of our galaxy
- The ultimate fate of our Sun
- Quasars are distant galaxies with a Black Hole in the centre, so distant that they look like stars.
- FAST Radio bursts, including Gamma Ray Bursts (GRBs), are from extragalactic distances. Events that last a few seconds or less – a sign of merging neutron stars or evidence of Hypernovae (not novae or supernovae)!
- Neutron Stars in Binary Systems, accretion discs and “spiders”
- Neutron Stars as a cosmic GPS for future space travellers
- Detect Gravitational Waves using neutron stars. Gravitational Wave detectors are not very sensitive, so they can only detect high-energy events, such as the collision of two neutron stars or the formation of black holes.
- Space-borne Gravity Wave detectors, such as the Laser Interferometer Space Antenna, which NASA plans to launch in the 2030s, will be able to detect a wider range of cosmological phenomena.
- Square Kilometer Array’s role in detecting more neutron stars, pulsars and even pulsars orbiting black holes
- Pulsar Timing Array – a GPS for interstellar travel
Episode 115 – Professor Michael Garrett & Jodrell Bank Centre for Astrophysics
In this episode with Professor Mike Garrett FRS, we discuss some of the many research activities conducted by him, his colleagues and students at the Jodrell Bank Centre for Astrophysics (JCBA) University of Manchester. Many of these activities involve international collaboration and are thus conducted elsewhere around the world and not just in Manchester. One of the big takeaways for me was the work of Mancunian Dennis Walsh who made the very first Gravitational Lensing observation from Jodrell Bank. He was also Professor Garrett’s PhD supervisor.
A shorter version of this interview was broadcast on Allfm.org 11th June 2024.
Some of the topics we discussed include:
- Recollections of working with Sir Bernard Lovell
- Gravitational Lensing and its origins at Jodrell Bank through the work of Dennis Walsh
- JBCA’s long association with Search for Extraterrestrial Intelligence and how the increased funding via the Breakthrough Listen Programme, has increased SETI research by acquiring more time on existing radio telescopes including Parkes and Greenbank. Also introducing new approaches to SETI research. Rather than collecting new data, the new approach involves analysing open source data from Earth and spaceborne sources including the European Southern Observatory, Alma Observatory and the WISE spacecraft.
- More than 150 individuals from the University of Manchester are associated with the international program the Square Kilometer Array, headquartered in Manchester.
- The global increase in the use of Low-Frequency Array (Lofar) technology in Radio astronomy.
- The USA, Europe and China are looking at the far side of the Moon as a location for radio astronomy
- The role of Brexit and its impact on Britain’s capacity to participate and lead in internationally collaborative programs.