‘Life as We Made It’ charts the past and future of genetic tinkering

With genetic engineering, humans have recently unleashed a surreal fantasia: pigs that excrete less environment-polluting phosphorus, ducklings hatched from chicken eggs, beagles that glow ruby red under ultraviolet light. Biotechnology poses unprecedented power and potential — but also follows a course thousands of years in the making.

In Life as We Made It, evolutionary biologist Beth Shapiro pieces together a palimpsest of human tinkering. From domesticating dogs to hybridizing endangered Florida panthers, people have been bending evolutionary trajectories for millennia. Modern-day technologies capable of swapping, altering and switching genes on and off inspire understandable unease, Shapiro writes. But they also offer opportunities to accelerate adaptation for the better — creating plague-resistant ferrets, for instance, or rendering disease-carrying mosquitoes sterile to reduce their numbers (SN: 5/14/21).

For anyone curious about the past, present and future of human interference in nature, Life as We Made It offers a compelling survey of the possibilities and pitfalls. Shapiro is an engaging, clear-eyed guide, leading readers through the technical tangles and ethical thickets of this not-so-new frontier. Along the way, the book glitters with lively, humorous vignettes from Shapiro’s career in ancient DNA research. Her tales are often rife with awe (and ripe with the stench of thawing mammoths and other Ice Age matter).
The book’s first half punctures the misconception that we “have only just begun to meddle with nature.” Humans have meddled for 50,000 years: hunting, domesticating and conserving. The second half chronicles the advent of recent biotechnologies and their often bumpy rollouts, leading to squeamishness about genetically modified food and a blunder that resulted in accidentally transgenic cattle.

As we teeter on a technological precipice, Shapiro contends we have a choice to make. We can learn to meddle with greater precision, wielding the sharpest tools at our disposal. Or, she writes, “we can reject our new biotechnologies” and continue directing evolutionary fates anyway, “just more slowly and with less success.” Shapiro speculates about what the future may hold if we embrace our role as tinkerers: plastic-gobbling microbes, saber-toothed house cats, agricultural crops optimized for sequestering carbon. Whether these visions will come true is anyone’s guess. But one thing is clear. No matter which route we choose, humans will continue to stir the evolutionary soup. There’s no backing out now.

Ancient human visitors complicate the Falkland Islands wolf’s origin story

The enigmatic, now-extinct Falkland Islands wolf had human visitors on the remote archipelago up to 1,070 years ago. The find suggests that Indigenous people could have originally brought the foxlike creatures, also known as the warrah, to the islands.

Scientists have debated how the islands’ only land mammal journeyed to the region: by a long-ago land bridge or with people. But little evidence of a human presence before Europeans arrived in 1690 had been found. Now, traces of ancient fires and hunting show that Indigenous people arrived on the Falkland Islands centuries prior to Europeans, researchers report October 27 in Science Advances. The Yaghan people — historically fire-wielding seafarers who kept foxes as companions — may have been the visitors.

Abrupt spikes in charcoal levels in sediments offer “telltale signs of human arrival” from 1,070 to 620 years ago on New Island, says Kit Hamley, a paleoecologist and archaeologist at the University of Maine in Orono. Those spikes mirror later traces of Europeans’ fires around 250 years ago.

And massive piles of sea lion and penguin bones imply hunting by humans from 745 to 600 years ago, Hamley says. Before being hunted to extinction by Europeans in 1875, the Falkland Islands wolf (Dusicyon australis) also consumed marine predators such as sea lions and penguins, nitrogen levels in two warrah bones and one tooth show.
The researchers newly dated that tooth and found it to be from 3,860 years ago. That vastly predates the fire-and-bone-pile evidence, leaving a gap “between when the warrah arrives, and when we can definitively say people were there,” Hamley says.

But Indigenous people’s presence up to 1,070 years ago raises new questions about whether the warrah hitchhiked there with earlier human visitors, Hamley says.

Next, Hamley and colleagues plan to partner with the few remaining Yaghan communities in Tierra del Fuego in Argentina to piece together “parts of the story that have been lost or taken away.”

Pig organs for people move closer to reality

Luhan Yang
Biologist
Qihan Biotech

When featured in 2017, Luhan Yang had cofounded and was chief scientific officer of eGenesis, a biotech start-up. She is now cofounder and CEO of Qihan Biotech, based in Hangzhou, China, which aims to develop animal organs that are safe for human transplant and to make cell therapies that can treat conditions such as cancer and autoimmune diseases more widely accessible.

What is some of the most notable progress in your work since 2017?
The concept of xenotransplantation is to use animal organs as an alternative resource for human transplantation, since there is a huge unmet need for organs. There are two fundamental issues to be addressed. One is [that] there are endogenous retroviruses in the pig genome — some virus sequences — and they can jump around within the pig genome. The viruses can also jump from the pig cell to the human cell. So there is a potential cross-species transmission, which is a huge safety and regulatory concern.… The second hurdle of using pig organs for human transplant, as you can imagine, is rejection, and it is tremendous.

Those are the two fundamental problems … and that’s where we think gene editing can come into play. By 2017, our team had knocked out 62 [retrovirus copies]. Since then, there are three notable milestones: First, we have created our Pig 2.0, with 15 modifications for immunology…. Last year in Nature Biomedical Engineering, we showed that those modifications are properly expressed in the pig cell, and the resulting pig is healthy, as well as fertile, and the genetic modification can be passed to the offspring. The second part is we combined the [retrovirus] knockout and the immune rejection–related modification in a single pig. We call it Pig 3.0. So that is a prototype close to clinical trial.

The third part is the most exciting part for us: We need to test the function. [In a recent study published in the American Journal of Transplantation,] we put the pig kidney into a monkey. If it’s a normal pig kidney, it will be rejected in a few minutes. And right now the longest survival of our monkey is about one year.… The monkey experiment demonstrates the possibility of achieving long-term xenotransplantation.

What was it like to move from the lab to leading a company?
Being a leader in biotech is not all business. There are three components that are needed. The first part is to set the vision and strategy of the company. In such an innovative area, I think the scientific knowledge, the breadth of the exposure, I think that’s my strength.… The second part is to recruit, retain and train people. And the last part is some business judgment, like how to do fund-raising, how to organize a project, the accounting. I have to admit, I’m not the expert. But I think at my position, the key is to recruit the best people to do the job.… And I started to embrace that every leader has different strengths and weaknesses.

How has the pandemic influenced your company’s international collaborations?
I was hoping we could have more in-person meetings or travels, but right now, China still has the quarantine policy that makes it super inconvenient for international travel. Hopefully with the vaccine, the world will become what it was.

I feel the world is more divided compared with 10 years before. And I hope at least for medicine, we can see that our enemy is not a different country, but our enemy is cancer, is organ failure, is COVID, that we can keep and strengthen the collaboration across borders.

— Interview by Aina Abell

Breaking the one test for one cancer paradigm

Isaac Kinde
Molecular biologist
Thrive Early Detection

Isaac Kinde, featured in 2015, is developing tests to detect cancer early, when treatment is more likely to be successful. In 2019, PapGene, a small biotech start-up where he was chief scientific officer, was acquired by Thrive, cofounded by Kinde. Just this year, it got the backing of the much larger cancer diagnostics firm Exact Sciences.

Could you tell us about Thrive and what spurred this transition?
Thrive basically acquired the predecessor company [PapGene]…. There was a lot more money, there’s a lot more expertise, but the core mission didn’t change, which is to develop cancer diagnostic products that we think will have an impact on the lives of people with cancer. We have essentially turbocharged and focused our efforts, leading with the most promising product, which is CancerSEEK.

The premise is we can reduce cancer morbidity and mortality through earlier detection. CancerSEEK is a blood test, and it is a multi-cancer test. That contrasts with the current paradigm, which is one test, one cancer.… Right now, all of our efforts are on making it commercially available.

CancerSEEK, which is still in testing, picks up on DNA mutations and proteins associated with cancer. How many cancers can it detect at this time?
There’s good evidence for detecting over 60 to 70 percent of the cancers that cause the most deaths per year. That boils down to … colon, breast, lung…. But the [full] range is bigger than those three. There’s esophageal, gastric, kidney, pancreatic. There’s data that support maybe 12 to 13 different cancers.

You published what you’ve referred to as a “landmark study” in Science last year. What did it find?
We call it a landmark study because it was the first demonstration in a prospective setting of how a multicancer blood test could be used in real time to report results to patients with cancer.

We looked at 10,000 women in the Geisinger Health system. It’s primarily women who are in Pennsylvania…. In the study, 24 [women had cancers] detected with standard-of-care screening: colonoscopy, mammography or low-dose CT scan for lung. Then there were 26 cancers in which the CancerSEEK test detected the cancer first…. Sixty-five percent of the cancers we detected were at a stage prior to stage 4. So [the addition of CancerSEEK] doubled the number of cases that were [found before symptoms were reported] — in many, many cases early enough where some effective therapies could be implemented.

And then it was also safe…. There were very few false positives, and we could very quickly resolve the false positives with whole-body PET-CT imaging. At least two patients [who first had detections from CancerSEEK] had their cancers successfully removed and are thriving as of the last time we checked.

Routine cancer screenings fell during the pandemic. Has this affected your work?
It fans the flame, right? The reason why cancer screening went down is not because there was less cancer. It was [just] more difficult for whatever reason to get the appropriate standard-of-care test.… All this did was just strengthen the case that more tools, easier tools are needed for cancer screening. And I think maybe the other feeling is just wishing we could go even faster, but balancing a commercial launch with having all the right pieces in place that will set us up for success.

— Interview by Ashley Braun

How social stressors mark our genes

Jenny Tung
Evolutionary anthropologist
Duke University

Jenny Tung, featured in 2018, studies how social environments — including social status, relationships and isolation — influence primates’ genes and health. Her study subjects have included captive rhesus macaques and wild baboons.

What has been the most notable progress in your work since 2018?
We have built layers of complexity onto [our] initial story. A few years ago we were showing that it’s possible for social interactions to have profound effects on the function of our genome. And now we’re trying to derive a much better understanding of how and why and when, and what are the exceptions.

The other thing I’m really excited about is our ability to move away from this very powerful but very artificial system using captive primates and to ask about what’s going on in the field with wild monkeys. I’ve studied wild baboons in Kenya for many, many years. We know a lot about the social environments, the social experiences. And now with the ability to collect some simple blood samples, we’re also seeing strong signatures of things like social status and social integration, social bonds, social connectedness in the function of these animals’ genomes. That’s pretty exciting because lab studies are powerful and wonderful, but there’s always this question of, “Well, is this real in the real world?”

You were named a MacArthur Fellow in 2019. What have you been pursuing since?
It was a real honor. It has encouraged us to continue down some of these paths … and to also do some more comparative work and think about species beyond the ones that I have traditionally studied. So in the past few years, I’ve picked up work in other social mammals — wild meerkats and these very social rodents called mole rats — that have their own advantages in giving us insight into how our social world has shaped both how we came to be, our evolutionary past, and how we do day to day in our present.

I’ve been doing more work on something that’s an old love of mine: trying to understand the evolutionary consequences of intermixing between different primates. The population of baboons that I study in Kenya actually sits right at the edge of where the ranges of two different species of baboons meet. And so this population is intermixed between one species, the Anubis baboon, and this other species, the yellow baboon.… We think those patterns of intermixture influence some things about what [the animals] look like, how they behave and so on.…

We know that [humans] have also intermixed a lot with some groups that don’t even exist today, like Neandertals and Denisovans. That process of admixture that we observe right now in living primates [is] potentially relevant to understanding our species’s history.

What are some of the greatest challenges you’ve faced since 2018?
In many ways, I felt very fortunate during the pandemic; as an academic with tenure, I have a secure job. But we were also home with a 3-year-old for a long stretch. I spend usually at least a month a year in Kenya, and I have since 2006. But not in 2020. We had to figure out some way of keeping [the research] continuous without any ability to travel there. We have a permanent staff in Kenya — they are Kenyan — who are very important to us and have been working with our project in some cases for many decades, and they were having their own issues, and isolation, and risks in the face of a lot of uncertainty.

I spend a lot of time in my research life thinking about social interactions. And every species that I study … they live in groups. And humans, to a large extent, we live together. We didn’t evolve to be on our own for a long period of time. And so I spent a lot of time reading and thinking and working on, “Why when you don’t have the right sort of social connections, why does your risk of death just shoot up? What’s the consequence of chronic social stress?” One of the things that I really appreciate in a more visceral manner [now] is how important my social network is to me. I think that we’re all looking for ways to connect during the pandemic. And that’s when your personal experience and the things that you’re writing papers about and thinking about really collide.

— Interview by Aina Abell

From fair schools to vaccine distribution

Parag Pathak
Economist
MIT

Parag Pathak, featured in 2019, strives to make public education more equitable. He has used data and algorithms to overhaul school choice systems in Boston, New York and other U.S. cities. Now he’s applying his research to the question of how to equitably distribute vaccines and other medical resources.

What’s the most notable progress in your work since 2019?
Since we last talked, I released a paper on the effects of universal preschool. A lot of people are interested right now because [universal preschool, which is open to everyone with no income rule,] is part of the White House’s agenda. Because of the work we had done with Boston with their school choice algorithm over the years, we had some files on school admissions going back to the late 1990s. Boston was a leader nationwide in expanding slots for children in preschool. But, like many cities, there weren’t enough slots for demand, so they had to ration. And that’s where the lotteries come in.

Fast forward to now. We linked these applicant cohorts to standardized test scores and educational outcomes all the way into college. And what we found was pretty exciting: Those who won the [preschool] lottery are more likely to graduate high school, they score higher on SATs and they’re more likely to enroll in college. Boston has continued to refine and try to improve [the lottery system]. It’s a model for other cities that are expanding public preschool.

Are you pursuing any new questions or projects?
COVID-19 was this huge shock. We all were looking around for how we could be useful, using our respective toolboxes. Tayfun Sönmez, M. Utku Ünver and M. Bumin Yenmez, all of Boston College — the four of us — started to study how scarce medical resources are rationed. And it turns out, there are some parallels with the way school seats are rationed.

One of the ideas that we’ve explored is the idea of a reserve system. In cases where people can’t agree on what’s fair, who should get a vaccine first? It’s very similar to who should get into a school. And the way that [schools] have handled that is they set up more elaborate versions of priority systems. With a vaccine reserve system, you basically have a [supply] that’s reserved for cardiac communities, and one that’s reserved for frontline medical personnel, so on and so forth…. States like California and Massachusetts have used some of our ideas [for their reserve systems].

My wife [Ruma Rajbhandari] is a medical doctor, and my sister [Sapana Adhikari] is an emergency room physician. A big part of my interest in medical rationing guidelines was their having to go to the hospital in March 2020 not knowing what the risks were and not having personal protective equipment. That was something that got me really keen on this debate about frontline health care workers, do they get first priority or not?

How has the pandemic shifted how you view your work in the area of education?
I have a kindergartner who was virtual this past year. And he did an amazing job with it. I think what the pandemic has done is rip the Band-Aid off on these lingering problems in society — inequitable access to health care, inequitable access to education, inefficiencies in both of the systems — and has made them much more pronounced. That’s been the theme of our research throughout. We hope more people take these issues on, because the way COVID-19 played out was really a scarring event in terms of haves and the have-nots.

— Interview by Cassie Martin

Speaking out for women in science

Jessica Cantlon
Cognitive neuroscientist
Carnegie Mellon University

Jessica Cantlon, featured in 2016, studies the evolution and development of complex mathematical thinking, including the traits that set humans apart from other primates. In 2017, she was recognized as a Time Person of the Year, as a “silence breaker” speaking out against sexual harassment during the height of the #MeToo movement.

What has been the most notable progress in your research since 2016?
We’ve expanded our repertoire to compare people across different cultures, who have different educational practices. We’ve been going to Bolivia to work with this group of people called the Tsimane, who live in rural parts of the Amazon forest. They don’t have the rigid, formal schooling where kids go through these particular curricula to achieve mathematical cognition. Instead, education there is more organic and more deeply connected to their way of life. That allows us to try to understand what effect does a particular type of education have on numerical thinking.

There was one study that we did, comparing species — nonhuman primates and humans — to understand the evolution of these concepts. Across all species and stages of development and cultural groups, there’s this bias that when you’re looking at a set of objects, and you’re trying to quantify it, you think about that set numerically. And you don’t have to; you can think about that set of objects spatially, as an amount of stuff, you can think about how much surface area is there, or the perimeter around it. But primates, including humans, [tend to] think about that set as a set of discrete objects, and count them up.

What is something that excites you right now in your work?
We’ve looked at the similarities and differences between boys and girls as their brains develop. We’ve done some of the first, early studies comparing children’s brains that can truly allow us to collect evidence on the trajectory of similarity between boys and girls…. We’ve shown that very early in development, between around 3 and 8 years of age, there’s evidence during mathematical processing that most of the brain — over 95 percent — shows functional similarity in that processing between boys and girls.

But as we know, much later on in development, we see a severe underrepresentation of girls in mathematics-related fields. What’s happening? There’s evidence in the field … that what happens in late childhood and adolescence is that children’s interests are shaped culturally.

What are some of the greatest challenges you’ve faced since 2016?
In 2016, [some of my colleagues at the University of Rochester and I] filed a sexual harassment complaint against a faculty member in our department who was sexually harassing women — undergraduate and graduate students and faculty. It became this situation that hijacked my career for a number of years.… We went public with our complaint, partly to protect ourselves, but also partly to let people know at other universities that this kind of thing is happening to students, and it’s affecting women’s career paths in ways that are discriminatory and unequal.

Ultimately, it was really important. Our complaint went public in September of 2017. In October 2017, the Harvey Weinstein story came out in the New York Times, and that kicked off a series of reactions that ultimately culminated in millions of people saying #MeToo, which I think was really powerful and important, and was something that we got to be a part of.

I’ve had dozens of women reach out to me for advice, about how to file a complaint at their university, how to take legal action, if that’s what they’re thinking, what the risks and benefits are. And so, part of my career now — and I’m excited by it, and I think it’s really important work — is to be an advocate for women who are experiencing discrimination and harassment at universities.

One response that we thought was really great was that the National Academies of Sciences, Engineering and Medicine did a full study on sexual harassment in the sciences…. It has a lot of ideas about what might effect larger-scale change.

— Interview by Aina Abell

How our SN 10 scientists have responded to tumultuous times

ach year since 2015, Science News has featured the work of outstanding early- and mid-career scientists in our SN 10: Scientists to Watch list. They’re nominated by Nobel laureates and members of the National Academy of Sciences, and are recognized because of their curiosity, passion, determination and, of course, their discoveries.

But we decided that 2021 begs for something different. The coronavirus pandemic continues to rage worldwide, with its burdens falling hardest on those least able to bear them — inequities already on our minds due to Black Lives Matter, #MeToo and other social movements. At the same time, we’re learning that the window to reverse some of climate change’s most devastating effects is closing fast. With all the upheaval, we wondered: How do these extraordinary times change a scientist’s work?

Here, we catch up with 10 noteworthy Scientists to Watch alumni. Emily Fischer, who studies wildfire smoke, has faced the threat of fires firsthand, cognitive neuroscientist Jessica Cantlon is fighting sexual harassment in the sciences and economist Parag Pathak is taking his efforts to make institutions more equitable from schools to hospitals. Other scientists reveal how their work has gained new urgency and meaning for them. The interviews that follow have been edited for length and clarity.

An ancient exploding comet may explain why glass litters part of Chile

Scattered across a swath of the Atacama Desert in Chile lie twisted chunks of black and green glass. How the glass ended up there, sprinkled along a 75-kilometer-long corridor, has been a mystery.

Now, analyses of space dust in the glass show that the glass probably formed when a comet, or its remnants, exploded over the desert 12,000 years ago, researchers report November 2 in Geology.

This corridor is the best evidence yet of a comet impact site on Earth, says Peter Schultz, a planetary geologist at Brown University in Providence, R.I.

There are only about 190 known impact craters on Earth (SN: 12/18/18). Falling space rocks carved out these sites, but none are known to have been created by a comet. That’s because comets, which are made of mostly ice and some rock, tend to explode before reaching the ground, a fate they share with some small asteroids. These fiery events — known as airbursts — are dramatic, generating massive amounts of heat and strong winds. But the effects are temporary and often fail to leave lasting imprints, like craters, behind.
That’s especially true in wet environments. In 1908, an airburst from an asteroid or comet over a remote part of Russia flattened trees and generated a shock wave that knocked people off their feet hundreds of kilometers away. The trees have since grown back over the site of what’s now known as the Tunguska blast, leaving just a marsh (SN: 6/5/08). “If it hadn’t been observed, no one would know it happened,” says Mark Boslough, a physicist at the University of New Mexico in Albuquerque who wasn’t involved in the new research.

The Atacama, the world’s driest desert, is better suited to preserving impact sites. And it’s full of sand — the raw material for making glass, which forms when sand is heated to high temperatures. Heat from volcanic activity is responsible for almost all of the naturally derived glass on Earth.

The desert’s glass corridor, however, is kilometers away from the closest volcano, suggesting the glass formed in a different type of heating event, such as an airburst. But radiocarbon dating of ancient plants in the soil around the glass seemed to indicate that the pieces didn’t all form at the same time. Because airbursts rarely occur in the same place twice, the evidence led some researchers to suggest that the glass formed during several massive grass fires.

That idea, Schultz says, “seemed really weird to us because there just wasn’t enough grass for fires,” even long ago when the area probably had more greenery than it does today. After examining some of the glass, he and colleagues determined that it had formed at temperatures exceeding 1700° Celsius — much hotter than grass fires.

What’s more, the team discovered embedded within the glass compounds found in comets sampled during NASA’s Stardust mission but almost never in asteroids (SN: 1/7/04). The only way for this space dust to have made its way into the glass is if a very old chunk of space debris, such as a comet, exploded at the moment that the glass formed, the researchers say.
Strong winds from an ancient comet’s explosion folded glass as it formed in what’s now the Atacama Desert, a study finds. Folds in the glass are visible in a microscope image (left) of a section from a larger chunk of glass (right). The yellow dot marks where the section was taken.
SCOTT HARRIS/FERNBANK SCIENCE CENTER
“It’s pretty clear that this is an impact,” Boslough says. “And in this case, there’s no evidence for a crater, so this event was a pure airburst.”

An airburst would also help explain why the glass appears twisted. “It was clear the glass had been thrown around and rolled. It was basically kneaded like bread,” Schultz says. Grass fires may melt the ground, but they rarely fling it around. Like Tunguska, the airburst probably generated strong winds that flung the glass as it formed, creating the folded look.

The violence of the impact would have scattered glass far across the desert and onto different layers of sediment. Because those layers formed at different times, that may have created the illusion that the glass was created during multiple events. Looking at the dating of plants that came in direct contact with the glass allowed the researchers to pin down the date of the probable comet strike to about 12,000 years ago.

That timing places the event about 800 years after a mysterious period of rapid cooling known as the Younger Dryas, which coincided with the extinction of many large animals. Some scientists have suggested that a comet exploding over the Northern Hemisphere set off a series of events that led to the frigid conditions, though the idea is controversial (SN: 6/26/18).

The timing of the Atacama comet strike shows that it wasn’t related to the Younger Dryas event, Schultz says, but the finding does lay the groundwork for identifying other potential comet sites on Earth.

Even without a link to the Younger Dryas, the Atacama impact would have left a strong impression on anyone who saw it. Archaeological evidence suggests that people lived in the area at the time and thus may have witnessed the airburst (SN: 11/30/15). “It would have seemed like the entire horizon was on fire,” Schultz says. “If you weren’t religious before, you would be after.”

A space rock called Kamoʻoalewa may be a piece of the moon

The moon’s violent history is written across its face. Over billions of years, space rocks have punched craters into its surface, flinging out debris. Now, for the first time, astronomers may have spotted rubble from one of those ancient smashups out in space. The mysterious object known as Kamoʻoalewa appears to be a stray fragment of the moon, researchers report online November 11 in Communications Earth & Environment.

Discovered in 2016, Kamoʻoalewa — also known as 2016 HO3 — is one of Earth’s five known quasisatellites (SN: 6/24/16). These are rocks that stick fairly close to the planet as they orbit the sun. Little is known about Earth’s space rock entourage because these objects are so small and faint. Kamoʻoalewa, for instance, is about the size of a Ferris wheel and strays between 40 and 100 times as far from Earth as the moon, as its orbit around the sun weaves in and out of Earth’s. That has left astronomers to wonder about the nature of such tagalong rocks.

“An object in a quasisatellite orbit is interesting because it’s very difficult to get into this kind of orbit — it’s not the kind of orbit that an object from the asteroid belt could easily find itself caught in,” says Richard Binzel, a planetary scientist at MIT not involved in the new work. Having an orbit nearly identical to Earth’s immediately raises suspicions that an object like Kamoʻoalewa originated in the Earth-moon system, he says.

Researchers used the Large Binocular Telescope and the Lowell Discovery Telescope, in Safford and Happy Jack, Ariz., respectively, to peer at Kamoʻoalewa in visible and near-infrared wavelengths. “The real money is in the infrared,” says Vishnu Reddy, a planetary scientist at the University of Arizona in Tucson. Light at those wavelengths contains important clues about the minerals in rocky bodies, helping distinguish objects such as the moon, asteroids and terrestrial planets.
Kamoʻoalewa reflected more sunlight at longer, or redder, wavelengths. This pattern of light, or spectrum, looked unlike any known near-Earth asteroid, Reddy and colleagues found. But it did look like grains of silicate rock from the moon brought back to Earth by Apollo 14 astronauts (SN: 2/20/71).
Ring around the sun
Kamoʻoalewa, also known as 2016 HO3, has an orbit (white) that is nearly identical to Earth’s (blue), causing the object to weave around Earth as it circles the sun.
“To me,” Binzel says, “the leading hypothesis is that it’s an ejected fragment from the moon, from a cratering event.”

Martin Connors, who was involved in the discovery of Earth’s first known quasisatellites but did not participate in the new research, also suspects that Kamoʻoalewa is a chip off the old moon. “This is well-founded evidence,” says Connors, a planetary scientist at Athabasca University in Canada. But, he cautions, “that doesn’t mean it’s right.”

More detailed observations could help confirm Kamoʻoalewa is made of moon stuff. “If you really wanted to put that nail in the coffin, you’d want to go and visit, or rendezvous with this little quasisatellite and take a lot of up-close observations,” says Daniel Scheeres, a planetary scientist at the University of Colorado Boulder not involved in the work. “The best would be to get a sample.”

China’s space agency has announced plans to send a probe to Kamoʻoalewa to scoop up a bit of rock and bring it back to Earth later this decade.