NASA’s Latest Asteroid Explorer Celebrates Our Ancient Origins in Space and on Earth

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Once upon a time, a being not quite human walked the earth. She was tiny, the size of a child, with a much smaller brain. She likely communicated with grunts, screams, and laughs like chimpanzees, but did not speak. And so she didn’t have a name, at least not one that we would think of as a name today.

When scientists discovered her bones in present-day Ethiopia, scientists gave her a name: Lucy. She was the first Australopithicus afarensis ever found, a hominid ancestor of present-day humans. It is not known whether A. afarensis was our direct ancestor or an offshoot of a common ancestor. But either way, her fossil – along with hundreds of others found later – offers clues to the origins of our own species, a chapter of our ancient past that we otherwise find difficult to dig up.

Three million years after Lucy’s death – possibly after she fell from a tree – a NASA spacecraft launched in October 2021 has traveled more than a hundred million kilometers from Earth on its way to the realm of Jupiter. The spacecraft’s body itself is small, only about the size of an adult human, but its mission is grand: to explore two asteroid clusters swept by Jupiter’s gravity, relics untouched since the dawn of the solar system.

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Billions of years ago, similar asteroids collided and grew until they became planets. Studying Jupiter’s asteroid fossils up close will advance our understanding of the origins of our own planet, a chapter of our ancient cosmic past that would otherwise be difficult for us to uncover.

For this reason, the scientists who designed and built the spacecraft named it Lucy.

A worthy tribute. But this tribute to our past was only the first for this astronomical anthropological mission.

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Almost all of the asteroids we observe in the solar system are anything but pristine; Instead, they have been battered, irradiated, and otherwise modified over eons of time. But thanks to a quirk of gravity, a particular subset of asteroids is well preserved. That’s because the combined gravity of the Sun and Jupiter creates stable regions that lead and lag the giant planet in its orbit by 60 degrees. These are the Sun-Jupiter points L4 and L5, where “L” is short for Joseph-Louis LaGrange, the Italian-born French polymath who worked out the existence of such points mathematically. They are gravitational traps in which objects can dwell for eons. Thousands of asteroids occupy them. The first discovered were named after heroes in Greek history of the Trojan War and are therefore known as the Trojan Asteroids, or simply Trojans, clustering around the Trojan Points.

Likely time capsules from the early days of the solar system, the Trojans are the target of the Lucy mission. The spacecraft is on a long looping path that takes it into orbit around Jupiter, first to L4, the leading Trojan cluster, then back to Earth for gravity assist, and then back to L5, the trailing cluster . Each orbit lasts six years, with Lucy examining more of these ancient rocks each time she reaches Jupiter’s orbit.

The spacecraft must also pass through the main asteroid belt each time. Its first encounter would be a main-belt asteroid four kilometers wide, designated 1981 EQ5. However, in 2015, not long after Lucy was approved and funded by NASA, the asteroid was given a proper name: (52246) Donaldjohanson, honoring the anthropologist who first discovered the asteroid’s fossilized bones A. afarensis Lucy in 1974.

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Matching again. But there is more.

Planetary scientist Raphael Marschall of the Observatoire de la Côte d’Azur in France studied the orbits of half a million main belt asteroids and looked for other potential targets for Lucy. He found one called 1999 VD57, a small asteroid about 700 meters across. Lucy would have been about 40,000 miles from it, but small maneuvers by the spacecraft have now brought it to within 280 miles of the asteroid, close enough for a good view of its shape and surface. This also makes the asteroid the first that Lucy encounters on November 1, 2023.

Given the circumstances, the Lucy team at the International Astronomical Union (the official guardians of astronomical categorizations) suggested a name that was quickly accepted: Dinkinesh, meaning “you are wonderful” or “wonderful one” in Amharic, a language used by Ethiopians .

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What makes this so wonderful is the Dinkinesh is the Ethiopian name for the hominin Lucy.

The first asteroid Lucy that the spacecraft will visit is now also named after Lucy herself and the second after her discoverer.

I think it’s all, well, wonderful. When I first read about these names, I was quite moved. Naming the mission after an ancient hominin was already a wonderful act by the Lucy team, connecting our past on Earth to the universe around us. Naming Dinkinesh shows respect for the Ethiopian people and their nation’s connection to our origins as people.

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With this, scientists not only honor what they study, but also the humanity behind the science.

It is in our nature to try to understand our origins; Every culture has a creation myth. For scientists, the origins of our planet and our species are compelling puzzles, the pieces scattered across time and space, and their scarcity makes them all the more valuable.

Along the way, our nature also compels us to give names to the things we study. It’s a beautiful tradition, a way to commemorate events and people who contributed to our history. This act has a deep meaning for us. As we are driven to explore, these names help us as we search for a connection to what we are studying. The way we make these relationships is more than a gesture; it reflects what we hold dear, a recognition of what and who we honor.

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I am, and always have been, baffled by the idea that scientists must always be detached, detached, dispassionate observers. Certainly this is the default position when we analyze data, but that doesn’t mean it has to be this way in every aspect of research – especially when it comes to probing our origins, both local and cosmic.

There is a deep joy in discovery, in the exploration of knowledge, and in advancing in the pursuit of truth. How can we not admire this endeavor, and how can we not want to celebrate those who have helped us in this quest?

This is an opinion and analysis article and the views expressed by the author or authors do not necessarily reflect those of Scientific American.