A “killer asteroid,” large enough to decimate Baltimore and the surrounding areas, may be heading toward Earth at this very moment.

No, I’m not talking about the one that scientists say arrived on Sept. 29, and will orbit our planet until later this month — I’m not worried about that one. Nor am I worried about the one expected to fly by on April 13, 2029, though it’s the size of the Eiffel Tower, is big enough to level Manhattan, and has the European Space Agency nervous. Even though they expect it to return again in 2036, and then again in 2068 — each time, edging ever closer to our planet — I’m not worried about that one.

I’m worried about the thousands of other dangerous asteroids scientists believe threaten Earth, that they cannot locate.

According to experts, we should expect an asteroid large enough to cause serious damage to hit the Earth approximately every 60 years.

They say they have identified most of the ones as large as the one that killed the dinosaurs — most of them, but not all of them. They are also having difficulty locating more than a third of the estimated 25,000 smaller asteroids that are also expected to threaten Earth in the coming decades.

In October 2022, scientists discovered a mile-wide “planet killer” hiding in the glare of the sun. It has since been removed from the running tally of dangerous asteroids, but they fear there may be others.

What worries them most is being caught by surprise, the way they were in 2013, when a smaller asteroid, traveling undetected from the direction of the sun, exploded in the skies over Russia.

That was a wake-up call for NASA. Afterward, they created a new department to better coordinate their early detection efforts.

Perhaps, like me, you’ve noticed an uptick in news coverage lately about asteroids? I started to really take notice after the surprise discovery of “Oumuamua” in 2017. That asteroid, a quarter mile long, was discovered only a month after it had passed the sun and was already on its way to Earth. Like many people, I was so caught up in the buzz about whether it was a cloaked alien starship, that it didn’t occur to me to wonder why NASA discovered it only weeks before it threatened us.

After learning about this most recent asteroid, the one that arrived on Sept. 29, I reached out to a friend who used to work high up at NASA — who was involved in the upcoming mission to Jupiter’s moon, Europa. She has never said much about her work at NASA, but she was particularly opaque when I raised the subject.

“Is it a coincidence that I’m seeing so much in the news lately about asteroids?” I asked her.

“No,” she replied.

“Should I be worried?”

“Yes, and no. The government thinks we can’t handle it.”

There are things NASA says we can do. For example, it successfully tested an “asteroid redirection” method in 2022. A small asteroid, which orbits a much larger one, was targeted and struck by a spacecraft — permanently reshaping it and altering its orbit. Provided we catch it in time, other options might also include: “using the gravity of a nearby spacecraft to tug on it, or blasting it with nuclear weapons, or sending a spacecraft to paint it white in order to change the amount of solar radiation it absorbs, and thereby causing a shift in its trajectory.”

Learning about what scientists know (and don’t know) about asteroids is a sobering experience. It’s only a matter of time before you begin to think that it’s a miracle a major strike hasn’t happened already. Such an awareness is enough to make a person ponder the meaning of life.

There is a famous poem by Mary Oliver called “The Summer Day,” in which she finds herself contemplating the origins of the universe, and whether a higher power exists, when a grasshopper flings itself out of the grass and into her lap, where it sits and eats sugar from her palm.

“I don’t know exactly what a prayer is,” she writes.

“I do know how to pay attention … how to kneel down in the grass … how to be idle and blessed … how to stroll through the fields, which is what I have been doing all day …”

“Tell me, what else should I have done? / Doesn’t everything die at last, and too soon? / Tell me, what is it you plan to do with your one wild and precious life?”

K. Ward Cummings is an essayist and social critic. He lives in Baltimore.