Today is the first class of your new four class set.. We will begin class with a casual conversation. We will go over the grammar together. We will finish class with a reading exercise. Your homework is to listen to the audio.
SACHA PFEIFFER, HOST:
There is a planet that has puzzled scientists for years. It orbits a star about 48 light-years away. Now, astronomers have taken a peek at this planet using the powerful, new James Webb Space Telescope. And as NPR's Nell Greenfieldboyce reports, what they saw was a surprise.
NELL GREENFIELDBOYCE, BYLINE: Thousands of planets have been discovered outside our solar system. They're called exoplanets. And this one goes by the unexciting name GJ1214b.
ELIZA KEMPTON: I like to refer to this planet as the most mysterious exoplanet that we know of. Maybe I'm biased.
GREENFIELDBOYCE: Eliza Kempton is an astronomer with the University of Maryland. She says this planet is bigger than Earth, but smaller than an ice or gas giant like Neptune. Scientists don't know what to make of it. Our solar system has nothing like it.
KEMPTON: Is it, like, a big, scaled-up Earth? Is it a small, scaled-down Neptune? is it something totally different that we've never seen before, maybe something called a water world, where the atmosphere would be all steamy?
GREENFIELDBOYCE: It's kind of important to find out because planets this size are all over the galaxy.
KEMPTON: They are actually the most common type of planet that astronomers know of today.
GREENFIELDBOYCE: GJ1214b is nearby and relatively easy to study. So since it was discovered over a decade ago...
KEMPTON: We've observed it with basically every telescope facility that one could think of.
GREENFIELDBOYCE: Astronomers hope to learn about the planet's atmosphere by analyzing the starlight that filters through it. But that didn't work.
KEMPTON: The planet is covered in these very thick clouds or hazes. Think of it, like, just a thick blanket over the entire top of the planet's atmosphere. So when you want to see into the atmosphere, instead you're just seeing this blanket that blocks everything.
GREENFIELDBOYCE: Enter the James Webb Space Telescope. This telescope detects infrared light.
KEMPTON: And infrared light is heat. So what we tried to do was to observe the heat coming off the planet.
GREENFIELDBOYCE: In the journal Nature, Kempton and her colleagues report that the planet is a lot colder than they expected. That means the planet is only absorbing about half of the incoming starlight. The rest is being reflected by the clouds or haze.
KEMPTON: And that's really the new big question now. We didn't expect the planet to be so reflective, and we actually kind of expected the opposite.
GREENFIELDBOYCE: She thought it would be dark, surrounded by a sooty haze. What's more, the telescope also saw signs of water vapor and methane in the planet's atmosphere. Laura Kreidberg was excited to see all this. She's a researcher at the Max Planck Institute for Astronomy who previously studied this planet with the Hubble Space Telescope.
LAURA KREIDBERG: It's extraordinary. You know, this planet has been kind of the white whale of exoplanet characterization for more than 10 years now, and so it's great to finally see some of its secrets revealed.
GREENFIELDBOYCE: She says the planet's reflective clouds make it shiny, even more shiny than Venus.
KREIDBERG: So we're going to have to go back to the drawing board to understand why the planet is as shiny as it is.
GREENFIELDBOYCE: She says it looks like this planet has an atmosphere that's mostly made of water. So it's not like Neptune, and it's not like Earth either. She says it's its own thing.
KREIDBERG: Really, really different from anything in the solar system.
GREENFIELDBOYCE: Even though this planet is way too hot to support life as we know it, she says learning about it should help scientists understand the full diversity of planets out there and how the Earth fits in. Nell Greenfieldboyce, NPR News.
(SOUNDBITE OF MAREN MORRIS SONG, "THE FEELS")