The President’s budget request proposed a 47% cut from NASA’s science budget. It includes the cancellation of upcoming missions such as Mars Sample Return, Nancy Grace Roman Space Telescope, DAVINCI, and VERITAS. It would also shut down a number of spacecraft that are already in deep space and collecting valuable science data, such as Juno, New Horizons, MAVEN, and Mars Odyssey.

As a space geek since childhood and a current employee of JPL, I am deeply concerned. However, I confess that I once became highly critical of spending taxpayers’ dollars on big space programs despite my childhood dream. But now I firmly believe that space exploration, particularly scientific exploration, is the nation’s responsibility to humanity.

Why did I once grow critical of my own dream? And why did I change my mind again? Well, it is a long, personal, and highly philosophical story. I don’t think my opinion is something everyone can agree on. But I thought it’s time to share the story. It is about dream, death, and the meaning of life and human civilization.

Opinions expressed in this article are my own and absolutely do not represent the views of my employer, but they might reflect some aspect of humanity.

Dream, Death, and Skepticism

One of the luckiest things that ever happened to my life was that I found my dream when I was quite young. In 1989, shortly before I turned 7, the Voyager 2 spacecraft made the first – and so far, the only – visit to Neptune. I was deeply inspired by the beauty of the distant planet, the marvelous discoveries that she made, and human’s ingenuity that built a machine that sailed across the Solar System over 12 years to the farthest planet. Since then, my dream has been to build a spacecraft like Voyager. The image of blue Neptune is like a tattoo in the deepest part of my mind. I have always been guided by the blue.

I also developed the fear of death quite young – well before I went to elementary school. Since grown-ups around me didn’t seem to worry about it, I thought the fear would disappear when I grow up. It didn’t. Of course, I don’t show it to anyone. And I am generally successful in suppressing it in my daily life. But now and then, the terrifying thought that this “I” will someday cease to exist suddenly comes back to my mind like a seizure. It most often happens when I am in bed. I sometimes scream in the night, making my family worry. It sometimes comes to me when I get drunk, come home, and look at myself in a mirror. I feel an urge to desperately escape, which is, of course, impossible.

Another thing that’s perhaps a little peculiar about me was that, in my adolescence and early adulthood, I did not like the stereotypical way of spending vacations where you stay in a resort hotel, lazily lie on a tropical beach, drink cocktails, and party at night. (I started liking it after having kids, except for the partying part.) I rather loved to explore the unfamiliar corners of the world myself. Perhaps I was influenced by my childhood hero, Voyager, the ultimate explorer. On every school break when I was in college and graduate school, I grabbed my backpack and the cheapest international flight with no advance reservations of hotels or local transport. I intentionally avoided developed countries since I thought I could go there on business trips in the future. Instead, I liked to get lost in the bustling Mercado del Centro of Latin American towns filled with the smell of every local agricultural product, drink delicious 10-rupee (=$0.15) chai sold by a dusty street cart in India, travel unpaved highway with local strangers in a bush taxi in Africa, play soccer with street kids, and engage in tough negotiation with a storekeeper who never misses an opportunity to charge 10 times more for tourists from rich countries.

Through those trips, I learned the harsh reality of the world. I felt helpless when I was surrounded by a crowd of kids selling souvenirs outside of the gate of a temple in Datong, a rural city in China (in 2002 when the country was poor), fighting each other over the one kuai ($0.15) coin I pulled out of my pocket. I met a boy in Banjul, Gambia, a refugee from Guinea-Bissau, who was eager to learn about science but had to make a living by selling fruit on the street. The boy did not know his birthday; he only knew he was born on Wednesday. On the streets of Varanasi, India, I had to ignore hundreds of extremely skinny beggars, often without a limb or two, if I wanted to walk through the city without exhausting my cash. And I saw countless bodies being cremated on the bank of the holy Ganges.

Quite naturally, a question came to form in my mind, which deeply conflicted with my dream: why do we spend billions of dollars to explore space when millions of people are suffering on Earth? The question is particularly troubling for scientific exploration. NASA and space agencies around the world have been spending billions to learn how the universe started or whether microbes existed on Mars billions of years ago. What would people I met on my trips think of it? Is it really the right thing to do?

I was in the middle of PhD in aerospace engineering when this question occupied my mind. I decided to give up my dream because I could not convince myself anymore that pursuing it was the right thing to do.

Lost. And Found.

So, what did I want to do after I left my dream? I didn’t know because I hadn’t had any other dreams. Well, I tried a few things to find something desperately. I enrolled in the Technology and Policy program at MIT in parallel with my PhD in the hope that I could somehow find a way to use my technologies to solve the “real” problems. (I didn’t find it, but instead, I found my wife there.) It was a great experience, but the classes on law or public policy were honestly not as exciting as engineering courses. I also started research on green tech applications and published a few papers. I was proud that my theory could help mitigate global climate change, but again, I found myself not as excited. Meanwhile, my graduation was near, and I had to find a job. I talked to a few NGOs for international aid, but they did not take an aerospace PhD seriously. I then tapped finance and consulting companies because their recruiters made me believe that those jobs would give me experiences that would somehow help me save the world one day. (Of course, they won’t.)

In short, I was lost.

Meanwhile, I kept being hit by the occasional death fear strokes. And I finally realized what I feared the most. It was not really the death itself. It was the thought that, at the final moment of my life, I would find that my life was meaningless.

So, what gives meaning to my life? I did not know. Or, more precisely, I did not know that I already knew deep in my heart.

After all, I still loved space. In 2010, I flew to Florida to see a Space Shuttle launch, as it was scheduled to retire the following year. It was a beautiful launch right before dawn. The white glaring ball of light rose to the sky, followed by a rambling noise and a glorious sunrise. The rocket plume was painted pink by the morning sun like a ladder to heaven.

I found myself crying. And I made up my mind. There were no logical reasons for the decision. It just came from the deepest part of my mind, the part that was tattooed by Voyager when I was little.

I decided to pursue my dream of space exploration again.

I once tried to leave my dream, but the dream did not leave me. I was, at last, found.

Since then, I earned my PhD and got a job at NASA JPL, where my hero, Voyager, was born. I am living in my childhood dream.

The launch of Space Shuttle STS-131. I decided to pursue my childhood dream once again when I saw it. Image: NASA

Memento Mori

Memento Mori (remember that you must die). The classic wisdom from many thousand years ago is still standing before us undecayed like the pyramids in Egypt. Because you must die, you want to make your life meaningful. What will make you think that your life is meaningful when you are on your deathbed?

As a father and a husband, I want my family to be happy. Providing for my family is definitely my top priority. Eggs and gas are quite expensive these days. On top of that, I need extra money for Netflix, Spotify, and Amazon Prime subscriptions. Of course, I dream of giving them more—perhaps a more spacious home or the latest vehicle with automated parallel parking. Every summer, I would love to spend a family vacation in exotic places. It would be extra nice if we could fly in business class instead of getting crammed into ever-shrinking economy class seats. Or, what about owning a private yacht? Sure, it spends 99% of the time sitting in a harbor, but wouldn’t it be nice if you could go for a spontaneous sailing trip to watch a beautiful sunset on the sea while sipping a cocktail?

So, if I get all of these, will that be enough to make me think that my life was meaningful when I die? Surely not. I imagined myself on the deathbed countless times. What I truly want is my wife, daughter, and son on my side, and perhaps my grandkids also, quietly talking about the happy moments we shared together. And I would look back on my life, and I want to be convinced, without any self-deception, that I have made a positive impact on space exploration as I dreamed when I was 6. Then, I will be able to rest peacefully.

We are creatures that look for the meaning of life. Why do “I” exist in this universe out of an astronomical miracle? It must not be meaningless. That is why I stubbornly pursue my dream no matter what.

But then, what about the question that I once had – how can we justify spending billions in space when millions of people are suffering on Earth? Did I forget about them? Definitely no. And I do have my answer. I know that it won’t convince everyone. I know many of you would disagree. Nonetheless, let me tell you.

Memento civitatem mori oportere

The conclusion of the Punic Wars in 146 BC marked the end of Ancient Carthage, which had prospered over seven centuries across the western Mediterranean, and the rise of Rome, the new ruler of the Mediterranean world. When Scipio Aemilianus, a Roman general who led the destruction of Carthage, witnessed the final moment of the great empire, he teared up and said: “This is a glorious moment, Polybius; and yet I am seized with fear and foreboding that some day the same fate will befall my own country.” He was correct. The same fate did fall on the Roman Empire about 600 years later.

I think it is quite natural to assume that, like individuals, civilization has a limited lifetime. I am not talking about countries or ethnic groups, but the civilization of the entire human race. I strongly hope its death will not come within the lifetime of my children or grandchildren. We must make every effort to ensure its longevity. Perhaps the death of civilization might not be a literal death, but a transformation to something different or assimilation into something else. Some may say that, in a distant future, humans will spread across the galaxy to outlive stars. Even so, our universe will someday drain all the free energy and reach the maximum entropy, called heat death. Stories will end. Music will stop. In its ultimate equilibrium, the cosmos will rest on everlasting idleness.

I argue that the philosophy of memento mori also applies to our civilization: memento civitatem mori oportere – remember that civilization must die. With an astronomical miracle, this great civilization was born on the third planet of an obscure G-type star in the periphery of an average galaxy. And it is as mortal as each of us is. Then, what is the meaning of it?

It is needless to say that the highest priority of our civilization is to provide for every member of it such that none of them won’t live in starvation or agony. (Side note: presently, the global food production is greater than the total calories needed for the entire population on the planet. But our economic system still allows food to go to the trash bins of lavish parties in America rather than the mouths of starving children in Africa.) It should also make egg and gas affordable. It should provide not just bread but “circuses” – i.e., leisure and entertainment. It should offer high-speed internet everywhere in the world for those who are happy to pay $6.99 for unlimited movie streaming  or play social games on their trip. It should keep producing better smartphones every year with more cameras, higher screen resolution, and longer battery life. And every Prime member should get one-day delivery if s/he buys $25 or more.

But is that the meaning of our civilization?

Think of the great civilizations in the past. The Mesopotamians are in the history textbooks of every country in the world because they invented agriculture and writing – two of the most influential inventions of humankind. The Phoenicians, who built Carthage, are remembered for their invention of alphabet. The Greeks, a collection of city states that were not particularly prominent in terms of territorial extent, are still considered one of the greatest ancient civilizations because of the philosophy, natural science, and mathematics that they produced. Why are you happy to pay €20 to see ancient little items like cups or utensils displayed in museums? It is probably not because you admire their materialistic wealth or military might. Rather, it is because they produced unique art, literature, culture, technologies, philosophy, or scientific knowledge that profoundly impacted humanity over thousands of years.

So, why does science matter?

Why does science matter?

Science is not just about finding the association between synthetic food dyes and ADHD or measuring the impact of greenhouse emissions on global climate change.

At its core, science is our urge to understand. And the urge is strong because we still understand so little about the heavens and the Earth. We don’t even know where we come from. For example, you drink a cup of water, which fills two-thirds of your body. It remains a scientific mystery where the water on Earth originated. Or you eat a two-egg omelet (reduced from three because of the egg price) at breakfast. Those eggs are rich in proteins, the building parts of your body, which are made of amino acids. Scientists are debating whether amino acids originated on Earth or came from outer space. We have little idea about how life popped up out of the mixture of water and chemicals. And science has not yet been able to establish a clear definition of life.

The clues to these mysteries are hidden in the planets, moons, and asteroids. That is why we explore space. For example, the analysis of the water ice trapped in the permanently shadowed craters of the Moon would tell us about the origin of water. The asteroid samples brought back by the OSIRIS-REX spacecraft (which is defunded in the FY26 Budget Proposal) contained 14 of the 20 amino acids. The exploration of Mars might help us understand how life evolved from non-living chemicals because it preserves ancient geological records that were lost on Earth. Some icy moons of Jupiter and Saturn are known to have vast underground oceans made of liquid water. Scientists suspect life might be living there. If we find alien life, it will be one of the greatest scientific discoveries of humankind, perhaps on par with Newton or Darwin. And it will positively answer one of the most profound philosophical questions of humanity: Are we alone in the universe?

Of course, we can live without knowing them. No animals except for humans ever bother about knowing where they come from or whether we are alone in the universe. They just eat, they sleep, and they mate. Knowing the origin of amino acids does not help them hunt prey or run from predators at all. But we are Homo sapience – man of knowledge. We somehow have an innate urge to know. Perhaps that is what separates us from other species. Perhaps that is the reason Nature tinkered with 1.5% of chimpanzees’ DNA and created another species with an outsized brain. Perhaps Nature wants to be understood.

This argument goes beyond science. I think what best defines humans is the things that do not help biological survival, yet our minds cannot live without them. Art, music, poems, and fictional stories are surely among them. Philosophy and science, too. And, of course, the kisses and hugs with the loved ones. If there is any meaning to the temporary existence of this civilization at an obscure corner of the vast great cosmos, it would be those activities that are “nonessential” but truly and uniquely human.

Of course, I am definitely not saying that art is more important than egg price, or space exploration is more urgent than food stamps. Like individuals, people’s well-being is absolutely the top priority of civilization. But some homeless people spend their precious savings to buy headphones to listen to music. No one can blame them for not spending money wisely. Because we are all human beings, we seek the meaning of life beyond physical health and material wealth. Likewise, I argue that civilization should also spend some fraction of its resources on endeavors to find the meanings of its existence – creating art, imagining fictional stories, and accumulating scientific knowledge to know who we are.

The taxpayers’ money that NASA spent on scientific exploration was $22 per person per year in the US *before* the proposed cut. As a comparison, it spent $5,600 and $2,600 per person per year on healthcare programs and national defense, respectively, in FY24. Of course, there would be a wide spectrum of opinions on what constitutes an adequate spending level. But I humbly think that $22 per person per year is a reasonable expenditure to find the meaning of human civilization in this vast, silent universe.

The Human Endling

On the night of September 7, 1936, a female Tasmanian tiger died in a zoo in Australia. It was also the moment when her species went extinct because she was the “endling” – the last known individual of a species.

Somewhere in the universe, at some point of time in the future, there will be the endling of Homo sapience. She will probably be aware that her death is not just the end of herself but also the end of civilization. She will probably reflect on the meaning of civilization on her deathbed. What will she think? If you were the endling, what would you do in your last moments?

In Arthur Clarke’s classic SciFi novel Childhood’s End, Jan Rodricks, the human endling, spent the last moments of Earth sitting before a piano and playing Bach.

If I were the one, I would sing What a Wonderful World. Or maybe Seasons of Love. Then, I would take Voyager 2’s picture of Neptune to my deathbed.