One underappreciated aspect of the current flood of exoplanet discoveries is the technical marvels that enable it. Scientists and engineers must capture and detect minute signals from stars and planets light years away. With the technologies of even a few decades ago, that would have been impossible – now it seems commonplace. However, there are still some technical hurdles to overcome before finding the “holy grail” of exoplanet hunting – an Earth analog. To help that discussion, a team of researchers led by Bertrand Mennesson at NASA’s Jet Propulsion Laboratory has released a paper detailing the current experimental and theoretical work around one of the most critical technical aspects of researching exoplanet atmospheres – starshades.
In particular, the paper discusses the technical hurdles of one of the most interesting upcoming space technology concepts. The Habitable Worlds Observatory (HWO) was called for as part of NASA’s recent decadal survey. While it is still early in its development cycle, the general outlines of how the HWO will work are evident, even if some technical details aren’t. And those general outlines point to the need for a starshade or coronagraph – or both.
The paper details the difference between a starshade and a coronagraph. By its definition, a starshade is a filter placed between the primary telescope mirror and the object it is observing. In contrast, a coronagraph is a filter placed between the primary mirror and the telescope’s sensor. Both methods have advantages and disadvantages regarding the data they allow the telescope to collect, but they can also be combined.
Starshades aren’t only useful for space telescopes, as Fraser discusses with Dr. Markus Janson in this video.
Several labs worldwide have been working on developing starshade and coronagraph technology. However, several nuances to the test set-ups affect their work’s applicability to the HWO project. Some tests are performed in a vacuum, while others are performed in air. Some tests are performed on monolith mirrored telescopes, while others are performed on segmented mirrors. Currently, the baseline operational mode of HWO is a space-based telescope, which, given current launch size constraints, also means it has to be segmented. So, only some tests performed to validate coronagraph and starshade technologies apply to the HWO use case.
For the relevant tests, there are three particular “key performance parameters” (KPPs), as the paper calls them, which can impact the technology’s viability. These are the image’s “raw” contrast, the “post-calibration” contrast, and the “off-axis throughput.” Each of these has thoroughly technical definitions described in the paper. But the first two can be thought of as how easy it is to see an exoplanet before (“raw”) and after (“post-calibration”) an image is run through a data processing algorithm. Off-axis throughput is the percentage of light from the planet through the starlight suppression system.
Each of these three KPPs represents a trade-off with the other two. Optimizing a starlight suppression system, such as a coronagraph or starshade, requires understanding and validating those design trade-offs. The paper mentions that the details of the HWO are still in flux, so it is impossible to determine what trade-offs must be made to have a fully functional system. Factors such as the number of exoearths the HWO is expected to observe, their orbital parameters, and how long the observatory will be allowed to capture data on any particular planetary system will all feed into the simulated trade-offs considered in the paper.
The Nancy Grace Roman Space Telescope is another candidate for exoplanet hunting with an advanced starlight suppression system, as Fraser discusses in this video.
Most importantly, the paper’s authors stated they intended to inform the technical committees of the HWO project about these trade-offs and to help guide the selection of mission parameters that might fit in with the current (or near-term) state of technical development of one of the most critical technologies for the optimal operation of the system. HWO is still in the early planning stages and has no expected launch date. Work has started around defining the teams that will make the technical determinations to inform the selection of a starlight suppression system for the HWO. Dr. Mennesson, the paper’s lead author, also happens to be one of the co-chairs of one of the committees.
But for now, there is plenty of time to flesh out the HWO design and continue developing and testing different starlight suppression technologies. If the remarkable pace of exoplanet discovery is any indication, with a little more time and attention, the telescope development community will develop an optimally designed system to help find one of the most sought-after discoveries in modern science.
The Martian surface shows ample evidence of its warm, watery past. Deltas, ancient lakebeds, and dry river channels are plentiful. When the Curiosity rover found organic matter in ancient sediments in the Jezero Crater paleolake, it was tempting to conclude that life created the matter.
However, new research suggests that non-living processes are responsible.
There are three carbon isotopes on Earth: carbon-12 (12C), carbon-13 (13C), and carbon-14 (14C). Earth’s carbon is almost entirely carbon-12. It makes up 99% of the carbon on Earth, with carbon-13 making up the other 1%. (14C is extremely rare and unstable, so it decays into nitrogen-14.)
In 2022, MSL Curiosity took an inventory of organic carbon in sediments at Gale Crater. Organic carbon is usually described as carbon atoms bonded covalently to hydrogen atoms and is the basis for organic molecules. The carbon in organic carbon can be either carbon-12 or carbon-13, and the amounts are important. At Gale Crater, Curiosity found about 200 to 273 parts per million of organic carbon. “This is comparable to or even more than the amount found in rocks in very low-life places on Earth, such as parts of the Atacama Desert in South America, and more than has been detected in Mars meteorites,” said Jennifer Stern, a Space Scientist at NASA’s Goddard Space Flight Center when the results came in.
This is the Stimson sandstone formation in Gale Crater on Mars. This is where the Curiosity Rover drilled the Edinburgh hole and found enriched Carbon 12. Image Credit: NASA/Caltech-JPL/MSSS
This carbon is important evidence in understanding Mars’ history. It can tell scientists about the planet’s atmospheric processes and environmental conditions and even shed light on potential life. In fact, understanding Martian carbon can aid our understanding of habitability and prebiotic chemistry on distant exoplanets. The isotope ratio in this carbon is different than on Earth. It has a lower amount of carbon-13 relative to carbon-12 compared to Earth. Why the discrepancy?
In recent research in Nature Geoscience, a team of researchers tried to understand the difference between Earth’s and Mars’s carbon isotope ratios. The work is titled “Synthesis of 13C-depleted organic matter from CO in a reducing early Martian atmosphere.” The lead author is Yuichiro Ueno, a biogeochemist in the Department of Earth and Planetary Sciences at the Tokyo Institute of Technology.
“Strong 13C depletion in sedimentary organic matter at Gale crater was recently detected by the Curiosity rover,” the authors write. “Although this enigmatic depletion remains debated, if correct, a mechanism to cause such strong 13C depletion is required.”
The amount of carbon-13 in the Martian sediments is far lower than in Earth’s sediments.
“On measuring the stable isotope ratio between 13C and 12C, the Martian organic matter has a 13C abundance of 0.92% to 0.99% of the carbon that makes it up,” lead author Ueno explained in a press release. “This is extremely low compared to Earth’s sedimentary organic matter, which is about 1.04%, and atmospheric CO2, around 1.07%, both of which are biological remnants and are not similar to the organic matter in meteorites, which is about 1.05%.”
The meteorite data is important because a four billion-year-old Martian meteorite named ALH 84001 is enriched in carbon-13, adding to the enigma of Mars’ carbon. Somehow, carbon-13 became depleted in the intervening billions of years. Solar escape is one possible reason for the carbon-13 depletion, but the authors discount that. There likely wasn’t enough time for enough carbon-13 to escape. “Furthermore, based on geomagnetic observations, early Mars probably had a geomagnetic field before 4?Ga,” the authors write. That field would’ve prevented solar escape.
To determine what’s behind this discrepancy, Ueno and his co-researchers simulated different Martian atmospheric conditions to see what would happen.
Their results show that isotope fractionation by solar UV light is responsible for Mars’ 13C depletion.
This graphic outlines the process that creates atmospheric organic matter that finds its way into the Martian sediments sampled by MSL Curiosity. Image Credit: Ueno et al. 2024.
Carbon-12 and carbon-13 respond differently to UV light. Carbon-12 preferentially absorbs UV, which dissociates it into carbon monoxide that’s depleted in carbon-12. What’s left behind is CO2 enriched with carbon-13.
Scientists have observed this process in the upper atmospheres of Earth and Mars. In Mars’ reducing atmosphere, where oxygen was depleted, the CO2 enriched with carbon-13 would’ve transformed into formaldehyde and possibly methanol. But those compounds didn’t remain stable. In Mars’ early days, the surface temperature was close to the freezing point of water, and it never exceeded about 27 Celsius (80 F.) In that temperature range, the formaldehyde and other compounds could’ve dissolved in water. From there, they gathered in sediments.
But that’s not the end of Mars’ carbon isotope story.
The researchers used models to show that in a Mars atmosphere with a CO2 to CO ratio of 90:10, 20% of the CO2 would have converted to CO, leading to the sedimentary carbon isotope ratio we see today. The remaining atmospheric CO2 would be higher in C-13, and both values are in line with what Curiosity found, and with the ancient Martian meteorite ALH 84001.
This is a plausible scenario that can explain Curiosity’s curious carbon findings.
The team’s study also includes some other important details. For instance, atmospheric CO may not have come solely from photolysis by UV light. Some could have come from volcanic eruptions. And atmospheric CO may not have been the sole source of organics that found their way into the sediments. But either way, the results tell scientists something about Mars’ carbon cycle.
It also tells us to expect to find more organics in Martian sediments in the future.
“If the estimation in this research is correct, there may be an unexpected amount of organic material present in Martian sediments. This suggests that future explorations of Mars might uncover large quantities of organic matter,” said Ueno.
While the research shows us that life needn’t be present to produce these organics, it can’t rule life out. Nobody can, at least not yet.
The research also shows how complex atmospheric chemistry can be and how difficult it can be to draw conclusions from atmospheric studies of exoplanets. The JWST has examined several exoplanet atmospheres and found some interesting results. But there’s so much we don’t know. This research is a reminder that any conclusions are likely premature.
As we discover more and more exoplanets – and the current total is in excess of 5,200 – we continue to try to learn more about them. Astrobiologists busy themselves analysing their atmospheres searching for anything that provides a sign of life. It is quite conceivable of course that the Universe is teeming with life based on very different chemistry to ours but we often look to life on Earth to know what to look for. On Earth for example, ozone forms through photolysis of molecular oxygen and is an indicator of life. Using the James Webb Space Telescope astronomers are searching stars in the habitable zone of their star for the presence of ozone and how it impacts their climate.
It’s tantalising that 425 of the exoplanets detected so far, exist in their stars habitable zone. It is in this region where the climate on the planet may well be suitable to sustain life. A significant subset of those planets are Earth-like in nature and will therefore have a fairly temperate climate. In addition, they all seem to orbit M-dwarf type stars which means they are likely to be impacted by tidal spin-synchronisation (due to the effects of the tides, one face of the planet may well be kept facing the star). One impact of this is the potential for large contrast in daytime and night-time irradiation which can drive strong convection on the day side of the planet.
The strong convection can drive winds around the equatorial region that are persistently higher faster than the rotation of the planet. It can also create Rosby Waves which naturally occur in the Earth’s ocean and atmosphere – in any rotating fluids or gas. Together these can control the distribution of chemicals in the atmosphere, in particular ozone.
In Earth’s atmosphere the presence of molecular oxygen is an indicator of life since it is produced largely from photosynthesis in plants. The molecular oxygen collides with nitrogen in the atmosphere to produce ozone so the presence of the latter is an indicator of biological processes. There is a chance though that the molecular oxygen in exoplanet atmospheres are the result of different ratios of near and far UV that can drive a non-biological build up.
In a new piece of research reported in a paper by lead author Paolo De Luca and team, they report their findings having leveraged climate model simulations on Proxima Centauri b. The Earth-sized exoplanet orbits the red dwarf star Proxima Centauri, the closest star to our own at a distance of 4,.2 light years.
An artist’s conception of a violent flare erupting from the red dwarf star Proxima Centauri. Such flares can obliterate atmospheres of nearby planets. Credit: NRAO/S. Dagnello.
They report that the analysis of atmospheres of tidally locked Earth-like exoplanets received a massive boost as a result of the development of the James Webb Telescope. The team reveal that their climate modelling (including the use of interactive ozone) globally increases temperature in the stratosphere. This in turn induces regional variations of surface temperature and also reduces the temperature contrast between day and night side.
Whilst the team have not been able to identify life on exoplanets, that was not their intention. What they have achieved is the ability to understand the exoplanet atmospheres using the James Webb Space Telescope, some of the processes that lead to atmospheric ozone and the impacts on temperatures.
To reach the Green Bank Observatory, you take the road less traveled, winding through scenic and remote regions of the Allegheny Mountains and the Monongahela National Forest of West Virginia. About an hour away, you’ll start to lose cell phone service. The Green Bank Observatory – a collection of radio telescopes that search the heavens for faint radio signals from black holes, pulsars, neutron stars or gravitational waves — sits near the heart of the United States National Radio Quiet Zone, a unique area the encompasses an area of approximately 13,000 square miles, spanning the border between Virginia and West Virginia.
Here in the NRQZ, human-generated radio transmissions are limited to shield the radio telescopes from Earth-based radio signals called RFI (Radio Frequency Interference), which are high-frequency electromagnetic waves that emanate from electronic devices such as computers, cell phones, microwave ovens, and even digital cameras. Even the weakest RFI signals can drown out the faint radio waves coming from the cosmos.
A view of the Green Bank Observatory’s Science Center and some of the telescopes. Credit: Jay Young for the Green Bank Observatory.
“You can only use basic, old-style film cameras here within 2 miles of the Green Bank Telescope,” said Paul Vosteen, Media Specialist at Green Bank Observatory who provided a tour of the facilities. Vosteen recounted a time he took a group out to see the gigantic (and very photogenic) 100-meter Green Bank Telescope (GBT) and unwittingly, a member of the group started snapping photos with a digital camera. While he quickly got the photographer stopped, Vosteen later coyly checked in with technicians who had been running diagnostics on the GBT that day. They were scratching their heads about a strange spike in signals earlier that morning. Turns out, it was the exact moment the photographer used their digital camera.
“The slightest electronic signal can cause interference,” Vosteen explained. “We can only use diesel vehicles here on the premises because gasoline engines have spark plugs. Everything that sparks produces radio waves.” Diesel engines, on the other hand, ignite by compression.
GBT Control Room. Credit NSF/GBO/Jill Malusky.
To keep the amount of interference on-site in check, the observatory’s control room and the nearby Science Center’s exhibit hall are completely surrounded by copper Faraday cages, wire-mesh devices built into the walls to block electromagnetic signals. Even windows are covered with a thin wire mesh, and the heavy door to the control room opens and closes like an entrance to a high-security bank vault.
Green Bank is home to six large radio telescopes ranging in size from 14 meters to 100 meters in diameter. The 20-meter and the 40-foot telescopes are full-time educational telescopes used by students around the country.
UT journalist Nancy Atkinson by the Reber Telescope, the world’s first parabolic dish built by Grote Reber in his Illinois backyard. The dish was moved to the Green Bank Observatory site in the 1960s. Credit: Nancy Atkinson.
The observatory also contains many relics of radio astronomy history. There’s an exact replica of the dipole array antenna Karl Jansky used when he discovered quite by accident that radio waves were emanating from the center of the Milky Way. That was the beginning of radio astronomy as we know it today. There’s also the actual parabolic dish radio telescope (the world’s first) built by Grote Reber in 1937 to follow up on Jansky’s detection. Then there’s the 85-foot Howard E. Tatel telescope that Frank Drake used in 1960 to perform the world’s first search for extraterrestrial intelligence with Project Ozma.
GBT – “Great Big Thing”
At 485 feet (148 meters) tall, the Robert C. Byrd Green Bank Telescope (GBT – sometimes called ‘Great Big Thing’ by locals) is the tallest and most eye-catching dish at the observatory, and the largest steerable radio telescope in the world. The maneuverability of its large 100-meter dish allows it to quickly track objects across its field of view, and see 85% of the sky.
While the GBT has been in operation since 2000, as we discussed in an article last week, a new upgrade for the telescope is under development. ngRADAR is a next-generation radar system that will allow the GBT to track and map asteroids with unprecedented resolution, making GBT the most advanced planetary radar system in the world. It will also be able to study comets, moons and planets in our Solar System. When finished it will not only help astronomers study the composition of other planetary bodies, but also help defend against potential large meteor strikes on Earth by mapping the precise trajectories of asteroids that cross Earth’s orbit.
Astronomers study the Universe by capturing light from stars, planets, and galaxies. But they can also study nearby objects by shining radio light on them and analyzing the signals that echo back. This is called planetary radar, and the process can reveal incredibly detailed information about our planetary neighbors.
The Robert C. Byrd Green Bank Telescope. Credit: Jay Young.
“When astronomers are studying light that is being made by a star, or galaxy, they’re trying to figure out its properties,” said Patrick Taylor, the project director for ngRADAR and the radar division head for the National Radio Astronomy Observatory, in our article last week. “But with radar, we already know what the properties of the signals are, and we leverage that to figure out the properties of whatever we bounced the signals off of. That allows us to characterize planetary bodies – like their shape, speed, and trajectory. That’s especially important for hazardous objects that might stray too close to Earth.”
Previously, the workhorse for planetary radar was the 1,000-foot-diameter (305 meters) Arecibo Observatory which collapsed in 2020, as well as the Goldstone 70-meter dish in California, which is primarily used for communicating with spacecraft as part of NASA’s Deep Space Network. Taylor said that the idea for ngRADAR has been discussed for years — even before Arecibo’s demise — but with the loss of Arecibo, the upgrade is even more important.
Radar signals transmitted by the ngRADAR at the GBT will reflect off astronomical objects, and those reflected signals will be received by the Very Long Baseline Array (VLBA), a network of ten observing stations located across the United States.
A Synthetic Aperture Radar image of the Moon’s Tycho Crater using the ngRADAR prototyope, showing 5-meter resolution detail. Image credit Raytheon.
“The idea is for GBT is to do the transmitting almost constantly and the VLBA — either all ten of those or any subset of those telescopes — doing the receiving,” said Taylor. “This new system will allow us to characterize the surfaces of many different objects in a different frequency or wavelength that hasn’t been used before.”
Radio Frequencies
All light travels through space in waves – think of how ripples move across a pond. Each ripple has a peak and a trough, which is called a cycle. An object emitting radio waves produces many cycles in a very short period. During each cycle, the wave moves a short distance, which is called its wavelength. Radio waves have the longest wavelengths in the electromagnetic spectrum. They range from sub-millimeter lengths to over 100 kilometers.
For radio waves of all wavelengths, the number of cycles per second is called a frequency, with one cycle per second being one hertz. That means one thousand cycles per second is a kilohertz and a billion cycles per second is a gigahertz. Radio astronomers are interested in objects in a wide range of frequencies, but mostly from between 3 kilohertz and about 900 gigahertz.
“Arecibo worked at 2.38 gigahertz, the Goldstone 70-meter primarily works at 8.56 gigahertz,” said Taylor. “For ngRADAR, we are looking at even higher frequencies, at 13.7 gigahertz, something that really hasn’t been used for planetary radar before. This is a way to offer something new and different, while the capabilities of the two instruments – GBT and Goldstone – also would complement each other.”
But more importantly, since Goldstone is now “the only planetary radar game in town,” as Taylor described it, that means planetary radar in the US has a single point failure. The antennas of Goldstone Deep Space Communications Complex are busy 24 hours a day communicating with spacecraft around the Solar System.
“If Goldstone is down for whatever reason or if it’s not available because of its work with the DSN,” said Taylor, “having a radar transmitter on the GBT gives us more flexibility and redundancy.”
Taylor said there are several applications for the future of radar, from not only advancing our knowledge of objects in the Solar System and characterizing asteroids and comets, but also aiding in future robotic and crewed spaceflight.
The Green Bank Telescope Credit: Dave Green
The GBT worked with the Goldstone telescope to help confirm the success of NASA’s Double Asteroid Redirection Test (DART) mission in 2022, the first test to see if humans could successfully alter the trajectory of an asteroid. In a two-week campaign, the radio telescopes were able to track how the orbit of Dimorphos, the asteroid that was hit by DART, changed after the impact.
But the main goal ngRADAR is for is planetary defense.
“That will be one of the highest priority uses for the radar system, where we can track and characterize near earth-asteroids and comets to evaluate any hazard they might present to Earth in the future. Radar delivers very precise data that allows you to predict where these small bodies will be in the future. We can determine its size, how it rotates, what it might be made of, is it just a round ball, or does it look like a potato, or does it have a moon that you also must worry about.”
Building ngRADAR
Raytheon’s prototype radar system deployed on the prime focus boom of the Green Bank Telescope over its 100-meter collecting dish. Credit: Green Bank Observatory.
As we discussed last week, a scaled-down prototype of ngRADAR at the GBT produced some of the highest resolution planetary radar images ever captured from Earth. Not only will the new full-scale system need to be built, but several changes will need to be made to the GBT.
“This will be a pretty intensive infrastructure project,” Taylor explained. “We’ll have to build the transmitter and mount it onto the GBT. With the size and weight of the system, as well as the cooling systems that will be needed, extra structures will be needed to support all that.”
Taylor said the timeline for completion would depend on funding, but a reasonable goal is that in the next five years – perhaps by 2029-2030 – ngRADAR could be up and running.
But Taylor feels that ngRADAR will allow the GBT to come full circle.
“Some of the first science done with GBT was receiving radar signals when it was first inaugurated,” he said. “It’s been a receiver for radar for over 20 years but now we are trying to take the next step and have it be a transmitter as well.”
After touching down on the moon’s far side, China’s Chang’e-6 lander is collecting samples to bring back to Earth — and sending back imagery documenting its mission.
Chang’e-6, which was launched May 3, went through weeks’ worth of in-space maneuvers that climaxed with its weekend landing in the moon’s South Pole-Aitken Basin region. The mission plan calls for the probe to collect samples of lunar soil and rock over the course of about two days, and then pack them up for the return trip.
If the operation is successful, Chang’e-6 would bring back the first fresh lunar samples ever collected on the moon’s far side — following up on the Chang’e-5 mission in 2020, which returned samples from the moon’s Earth-facing side.
The China National Space Administration said the lander used its onboard camera during its powered descent to detect obstacles autonomously and select a safe landing site. Chang’e-6 captured video imagery during the final phase of the lander’s descent and transmitted the views back to Earth. One video frame shows the shadow of the lander itself moments before touchdown.
Chang’e-6 is built to collect samples using a drill and a robotic arm. It’s also expected to gather scientific data about its surroundings using a radon detector, a negative-ion detector and a mini-rover. During surface operations, data and telemetry are being relayed between Chang’e-6 and Earth via China’s Queqiao-2 satellite.
Up to 2 kilograms (4.4 pounds) of lunar samples will be stowed inside the lander’s “ascender” stage. The rocket-powered ascender will then lift off from the surface and transfer the samples to the Chang’e-6 orbiter, which is currently in lunar orbit. Following the model set by Chang’e-5, the orbiter will head back toward Earth and release the sample capsule for atmospheric re-entry and touchdown in Inner Mongolia.
An image captured by a camera aboard the Chang’e-6 lander shows the spacecraft’s shadow on the lunar surface just moments before touchdown. (Credit: CLEP / CNSA)
The moon’s south polar region is of particular interest because it’s thought to harbor reserves of water ice that could support lunar settlement. Studying fresh samples from the South Pole-Aitken Basin could help scientists and mission planners learn more about the region’s resources.
Chang’e-6 is the latest spacecraft in an international armada of moon landers — including Russia’s Luna 25, iSpace’s Hakuto-R and Astrobotic’s Peregrine, which were unsuccessful, plus more fruitful missions such as India’s Chandrayaan-3, Japan’s SLIM and Intuitive Machines’ Odysseus.
Coming attractions include NASA’s VIPER rover, which is currently due to be delivered to the moon late this year; and China’s Chang’e-7 mission, which features a hopping probe and is set for launch in 2026. Looking further ahead, China aims to send astronauts to the lunar surface by 2030 — not long after NASA’s Artemis 3 crewed lunar landing, currently scheduled for 2026.
There was a time when maps of the Moon were created from telescopic observations and drawings. Indeed Sir Patrick Moore created maps of the Moon that were used during the historic Apollo landings. Now researchers have enhanced a technique to create accurate maps from existing satellite images. Their approach uses a technique called ‘shape-from-shading’ and involves analyzing shadows to estimate the features and shape of the terrain. Future lunar missions will be able to use the maps to identify hazards on the surface making them far safer.
Researchers at the Brown University in Rhode Island have helped refine a process used to map the surface of the Moon making it more accurate than ever before. In their paper, published in the Planetary Science Journal and authored by Benjamin Boatwright and team details the enhancements to the mapping technique. It can generate detailed models of the Moon’s surface to highlight craters, ridges and slopes from composites of 2D images.
Closeup of lunar surface (Credit NASA)
Highly detailed maps are of crucial importance to lunar missions and help the planners to identify the safest place to land. They can also use them to identify areas of particular interest that require further study enabling the whole mission to be far more efficient. Missions such as the Artemis project will benefit when it heads for the south pole of the Moon, an area which is not well mapped. High resolution maps of the area will aid the autonomous landing systems to avoid hazards.
Artist impression of Artemis lunar landing
Creating the maps is a time consuming job and is difficult to be accurate when lighting levels on target area are poor. The interpretation of shadows has been less than effective until now with the team addressing the issues. In their paper, the team explain how advanced computer algorithms can automate a lot of the process and improve the resolution of the generated models. Their new software gives lunar astronomers the necessary tools and information to create larger more detailed maps of the surface.
To allow lunar scientists to create a map from images requires at least two images of the same area. Each image must be perfectly aligned with its counterpart so that features in one are in exactly the same place in the other. Until now, the technology has not been able to take multiple images of an area and create a perfect map. Boatwright said ‘We implemented an image alignment algorithm where it picks out features in one image and tries to find those same features in the other and then line them up, so that you’re not having to sit there manually tracing interest points across multiple images, which takes a lot of hours and brain power.’
Along with the image alignment algorithm, the researchers created quality control algorithms and filters to remove poor quality images from the alignment process. By only inputing good quality images to the process means the output will be of far higher quality. It is a similar model that astronomical imaging employs when processing multiple images through stacking and alignment techniques.
To evaluate the accuracy of their work, the team compared the output from existing maps of the Moon to look for errors. To their delight, they found that maps created using their enhanced ‘shape-from-shading’ technique was more precise compared to those acquired during traditional techniques.
“It’s a developmental project, so it is what it is, but it is still uncertain as to when Starship can launch,” he wrote. “I can’t plan my future in this situation, and I feel terrible making the crew members wait longer, hence the difficult decision to cancel at this point in time. I apologize to those who were excited for this project to happen.”
DearMoon crew member Yemi A.D., a Czech choreographer, talks about the mission’s cancellation.
After a selection process that attracted more than a million applicants, Maezawa named eight artists and communicators, plus two alternates, to the crew in late 2022. One of the chosen crew members was Tim Dodd, a science communicator and YouTube video creator who’s known as the “Everyday Astronaut.”
“Of course I’m extremely disappointed, having dreamt about this mission since I first heard about it in 2018 and even more for the last three years since the selection process started,” Dodd wrote in an extended posting to X.
The mega-launch system now known as Starship was at an early stage of development in 2018 when Maezawa struck a deal with SpaceX CEO Elon Musk to reserve a round-the-moon flight. The mission was envisioned as a roughly five-day trip that would give artists and performers on the level of Pablo Picasso and Michael Jackson the chance to experience space — and work that experience into their artistic creations.
The cost of the dearMoon project was never disclosed publicly, but at the time that the plan was revealed, Musk said Maezawa was providing a substantial deposit that “will have a material effect on paying for the cost of development” of the Starship system. Back then, Musk said the total development cost was on the order of $5 billion.
Developing and testing Starship has taken longer than Musk planned — which is par for the course when it comes to new types of spaceships. During the most recent Starship flight test, which took place in March, the rocket reached orbital altitude but broke up as it descended to a planned splashdown. Another flight test could take place as early as next week.
This isn’t the first time Maezawa has backtracked on his plans for spaceflight. In 2000, he pulled out of a reality-TV project that would have traced the selection of a female contestant to accompany him on a round-the-moon trip, presumably aboard Starship. Despite that precedent, the crew members for dearMoon said they were surprised by the cancellation of a trip they’d been so looking forward to.
“You didn’t ask us if we minded waiting or give us an option or discuss that you were thinking of canceling until you’d already made the decision,” Rhiannon Adam, an Irish-born photographic artist who was chosen for the crew, said in an X posting directed at Maezawa. “I can only speak for myself, but I’d have waited till it was ready.”
Another would-be spaceflier, night-sky photographer Brendan Hall, said in an online statement that “the cancellation of this mission was sudden, brief and unexpected.”
Dodd echoed that sentiment in his posting to X. “The one thing I have a hard time reconciling is the timeline,” he wrote. “Had I known that this could have ended within a year and a half of it being publicly announced, I would’ve never agreed to it. We had no prior knowledge of this possibility.”
Dodd said he remained optimistic about the long-term prospects for citizen spaceflight. “I still firmly believe that, within my lifetime, we will see missions like this happen, and while I will never be the first to do such a mission, it brings me great joy to know the future is bright and exciting,” he said.
