You Should Know… Sarah Kaplan

Photo by David Holzel

If you’re looking to visit a nearby star system, or to investigate the possibility of pigs growing human organs, Sarah Kaplan is your guide. The 25-year-oid Brooklyn native has been a Washington Post science writer since 2016. Before that, she worked on the paper’s night shift.

Kaplan studied international culture and politics at Georgetown University. Lately her focus has been interstellar, such as her February story about the newly discovered star TRAPPIST-1 with its brood of seven “Earthlike” planets. We spoke in December.

When I was a kid, there were more planets than we have now, since Pluto got demoted. But there was less of everything else. And no exoplanets, except on “Star Trek.

Now being nerdy is cool. The TRAPPIST-1 story is one of my most read stories this year about the solar system and exoplanets.

As I read the story, I was trying to decide which planet was my favorite. If I was going to go to one and live there, which one would it be?

Well, we don’t know anything about them yet, we just know that they’re there. We’ve found thousands of exoplanets, but we can’t look at them directly. We don’t have telescopes that can take a picture of a teeny little planet next to a big, bright star.

So there’s a lot left to the imagination. Scientists can do some modeling, figure out what it might look like there, figure out if it’s in the habitable, Goldilocks zone.

Tell me about that phrase.

It’s the idea that it’s not too cold, not too hot. The important thing is that liquid water can exist on the surface, because everything we know about life on Earth is that we need water to have life. Three of the TRAPPIST-1 planets are in the habitable zone. They’re all close to each other and all really close to their star. So they think they’re tidally locked — the same way the same side of the moon always faces Earth, the same side of the planet always faces the sun and the other side is always in darkness.

Artist’s concept of the TRAPPIST-1 star system. NASA/JPL-Caltech

So depending on what that planet looks like, you could have one side of the planet that’s boiling hot and the other side is freezing cold. Or if the planet has an atmosphere that’s thick enough to circulate air it could be pretty pleasant. Or you could a terminator. That’s the point where light and dark meet and that place could be habitable. So because we don’t really know very much, it’s really exciting to imagine.

Trappist 1 is a red dwarf, so it’s very cool and most of its radiation is in the red and infrared. It would feel like sunset all the time.

I was at Johns Hopkins yesterday interviewing a cosmologist who studies the cosmic microwave background, which is the afterglow of the Big Bang. And just by looking at this very faint radiation from the beginning of the universe, he can tell you all kinds of things about what that moment looked like.

And it’s crazy to me that a) you can do that, and b) someone figured out that you can do that. How do you know that that’s what the physics is telling you?

Your job description as a science writer is to write about the bizarre, the groundbreaking and the controversial. Is there a story you’ve written that combined all three?

Yeah. In January [2017] there were two studies that came out within a day of each other about chimera embryos, which use genetic material from two different species. The idea is that one day you could grow a human organ inside an animal and then transplant it, because there are these huge wait lists for organ donations and people often die when they’re on the wait list.

One way to solve it is to take stem cells from that person, and that’s how a person’s own DNA can grow their own organ inside an animal.

One of these studies showed you can grow [an organ] using a mouse’s DNA in a rat and transplant it into the mouse. The next day, someone [demonstrated making] a human organ in a pig.

There are a lot of serious ethical questions about this. Ranging from, this is unnatural, we shouldn’t be messing around with the distinctions between species, to what happens to an animal that has human genetic material in it? Could that animal have a human consciousness? What if you grew a human embryo in a pig and it gave birth to a human? No one is doing that. But as a society we need to figure out what constraints to put on this kind of research.

So that’s bizarre – human-pig embryos. And controversial. And sort of inspirational. Imagine a day when nobody dies on an organ wait list.

You’re the author of the article “Wife crashes her own funeral, horrifying her husband who paid to have her killed.” Do you think that story was your “Citizen Kane” moment?

Morning Mix, which is the team I worked on on the night shift, seeks out compelling, sometimes disturbing, weird stories on the internet, and tries to tell them in ways that meet their full potential. That story was just a great yarn. I didn’t have to do anything except tell it. It was the story that broke the internet that day.

What was the top science story of 2017?

The eclipse. It was the most watched eclipse in human history. I saw the eclipse from Carbondale, Ill. I’m a person who’s primed to have an emotional response to this kind of thing — but it was really transcendent. And to have that many people experience totality and have shared that transcendent experience and hopefully came away with a feeling of being connected to the Earth and the moon and the fact that we’re on this spinning body moving around the cosmos. For a person who spends a lot of her time figuring out how to get people interested in science — the eclipse did my job for me.

Have a suggestion for a You Should Know profile? Candidates must be ages 21-40. Tell us what makes that person so interesting: [email protected].

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