MARY LOUISE KELLY, HOST:
It is time for our regular science news roundup with our friends at NPR's Short Wave podcast. This week it's Emily Kwong and Rachel Carlson. Hey, you two.
RACHEL CARLSON, BYLINE: Hey, Mary Louise.
EMILY KWONG, BYLINE: Hi.
KELLY: So how this works is you have brought us three science stories that caught your eye this week. What have you got?
CARLSON: Dark energy might be evolving over time.
KWONG: We have for you possibly the biggest marine reptile of all time.
CARLSON: And newly uncovered paintings at Pompeii offering a glimpse of life in an ancient time.
KELLY: Ooh, I love all of these, but let's go in order. Rachel, you were the one who mentioned dark energy, so start there. What are we talking about?
CARLSON: OK, Mary Louise. So to explain dark energy, we do have to go back in time just a little bit - like, 13 billion years to the Big Bang, this rapid expansion of the universe, everything. And after this explosion, the universe kept expanding. It's still expanding today.
KWONG: And in the late '90s, scientists figured out two things - first, that this expansion of our universe is speeding up over time and, second, that there had to be something behind this acceleration.
KELLY: Let me take a wild guess in the dark that this something is, in fact, dark energy.
CARLSON: That is correct - ding, ding. Yes. Our current model of the universe says dark energy is constant and will continue to push everything in the universe apart, so much so that one day, Mary Louise, other galaxies won't be visible from Earth. Even the stars in our own galaxy will die out, leaving behind a cold, dark nothing.
KELLY: OK, that is not where I was hoping this to go.
(LAUGHTER)
CARLSON: It's OK. This demise will happen over a trillion-plus years. So we'll long be gone.
KWONG: And there might actually be a wrinkle in all of this. So scientists have created a new 3D map of the universe using this device called DESY, which stands for Dark Energy Spectroscopic Instrument. And one of the researchers, Dillon Brout, says the map suggests that dark energy may be getting weaker over the last 11 billion years.
KELLY: The last 11 billion years - OK, so not so constant.
KWONG: Right. So that would mean dark energy is not a constant like we've previously thought. And if those findings are eventually confirmed, it would have drastic consequences for how quickly the universe expands. I talked to Priya Natarajan, an astrophysicist at Yale. She's not involved in DESY, and she said it's a little too early to tell how dark energy evolves. Maybe it'll get weaker. Maybe it'll get stronger. We don't really know. But the fact that it might change means...
PRIYA NATARAJAN: Our fate may not be as lonely and desolate and grim as we imagine.
CARLSON: Though both she and Dillon say we need a lot more data to know exactly what's going on here.
KELLY: OK. Subject No. 2, moving right along to the massive marine reptile - Emily, what's this thing actually look like?
KWONG: OK. Picture a dolphin, but it's the size of a whale, and it has an enormous mouth of teeth.
KELLY: That is terrifying. Go on.
CARLSON: It is. We're talking about the ichthyosaur, which means fish lizard. An ichthyosaur is an ancient marine reptile that swam in the oceans around the time of the dinosaurs.
KWONG: And a new specimen of the largest ichthyosaur to have ever lived has been found on a beach in Somerset in the U.K. - a whole bunch of fossils.
KELLY: Wow. How'd they find them? Who found them?
KWONG: OK, this is the coolest part. It was a father-daughter team of fossil hunters, Justin and Ruby Reynolds. So back in May 2020, Ruby, who was 11 years old at the time, and her dad were walking the beaches. And they noticed this weird rock that wasn't a rock at all. It was a bone. And they started looking in the area, and they found an even bigger bone in the mud.
RUBY REYNOLDS: The fossil I found in the mud slope looked almost like a tree branch but covered in clay.
KWONG: Ruby and her dad went on to find several pieces of what ended up being a giant ichthyosaur jawbone.
KELLY: And just elaborate on that. How giant are we talking?
KWONG: We're talking giant, about two meters or so.
KELLY: Yeah, OK, so, like, bigger than you or me.
KWONG: Yes, a creature with a jaw bigger than us. So the exact species they found is Ichthyotitan severensis, meaning giant fish lizard of the Severn.
KELLY: And how do they know that? I mean, how - just based on what they found, are they able to identify that these fossils belong to this particular species?
KWONG: Yeah. So Justin and Ruby called Dean Lomax, a paleontologist affiliated with the University of Bristol and the University of Manchester who had studied the only other known specimen. And he had always hoped a second specimen would turn up and was really impressed that the Reynolds family found this one all on their own.
DEAN LOMAX: Not only having found and identified these bones, but also one of the most important things of a discovery like this is doing the right thing and finding the people to work on this and ensuring it goes into a museum to ensure that it's safe for science and it's secure for the future.
KWONG: And, indeed, these jawbones will soon go on display at the Bristol Museum and Art Gallery for anyone to see.
KELLY: Speaking of art, let's end on these new paintings you're telling me were unearthed at the ancient city of Pompeii.
CARLSON: Yes. Have you ever been to Pompeii, by the way?
KELLY: I have. Have you?
CARLSON: Yes. OK, it's incredible, right? Like, it's in southern Italy. And I went on a high school field trip and was astonished, honestly, by how old it was, obviously, but also how big it is.
KWONG: Yeah. Pompeii covers an area of about 160 acres, and archaeologists have only excavated two-thirds of that. It's this ancient city that's been described as being frozen in time.
KELLY: Right, because the volcano erupted, Mount Vesuvius.
CARLSON: Yes, in 79 A.D. The eruption covered Pompeii in a thick layer of ash and other volcanic material, which helped to preserve this ancient city.
KELLY: OK, so that brings us to the paintings. What exactly have they found?
CARLSON: So these latest excavations have revealed a formal dining room that's about 50 feet long and 20 feet wide, with a mosaic floor of white tiles and black walls. And these walls are decorated with mythological characters inspired by the Trojan War. So, like, in one image, you see Helen of Troy and Paris, son of the king.
KELLY: Ah, yes, the famous lovers. Their affair led to the Trojan War.
CARLSON: Major drama, major gossip.
KWONG: At the time, yeah.
CARLSON: And in another image, you see the pairing of the god Apollo and Cassandra, who could see the future.
KWONG: So these paintings - they had a total social function as entertainment and points of conversation. Gabriel Zuchtriegel, the director of the archaeological park at Pompeii, says diners would meet there after sunset, and the flickering of their oil lamps would create this effect of the images moving, especially after a few glasses of wine.
KELLY: You're right. We've all been there.
(LAUGHTER)
KWONG: Some things never change.
KELLY: Indeed. OK, but what are we learning about Pompeii through all this?
CARLSON: So we talked with Cornell University archaeologist Caitie Barrett. She co-directs a different excavation at Pompeii, and she said the whole spectrum of ancient Roman society can be seen within this and earlier finds.
KWONG: For instance, next to this dining room is a recently excavated bakery where enslaved people worked.
CAITIE BARRETT: So you get both a glimpse at the lives of the ultra-rich and, at the same time right next door, the lives of people who were living at the bottom of Roman society and whose lives were much more difficult.
CARLSON: And she says all of it is right there at Pompeii.
KELLY: Thanks, you two.
KWONG: Thank you.
CARLSON: Thank you so much.
KELLY: That is Emily Kwong and Rachel Carlson from NPR science podcast Short Wave, where you can learn all about new discoveries, everyday mysteries and the science behind the headlines.
(SOUNDBITE OF CODY CLEGG'S "WHISPERS") Transcript provided by NPR, Copyright NPR.
NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.
