Sara Seager

Well, it turns out that many astronomers have a different version of a habitable planet. And that's because planets and stars come in all sizes and all kinds. So one of the short-term focus for astronomers is finding any kind of planet in any star's habitable zone. And the easiest ones to find right now with the telescopes we have are planets orbiting small stars.

Well, it turns out that many astronomers have a different version of a habitable planet. And that's because planets and stars come in all sizes and all kinds. So one of the short-term focus for astronomers is finding any kind of planet in any star's habitable zone. And the easiest ones to find right now with the telescopes we have are planets orbiting small stars.

There are stars out there that are half the size of our sun down to one tenth the size of our sun. These are called M dwarf stars. They're small red stars with a lot of magnetic activity. On those planets, there'd be a lot of northern lights. a lot of flares, a lot of star spots. And these planets are quite different from our Earth, actually. I like to call them Earth cousins.

There are stars out there that are half the size of our sun down to one tenth the size of our sun. These are called M dwarf stars. They're small red stars with a lot of magnetic activity. On those planets, there'd be a lot of northern lights. a lot of flares, a lot of star spots. And these planets are quite different from our Earth, actually. I like to call them Earth cousins.

They're not like an Earth twin. They're more like an Earth cousin because the star is so small and doesn't have much energy. And the stars give off flares a lot. And these Earth cousins, because they're so close to the star to get enough energy to be habitable, the habitable zone is quite close to the star because the stars give off very little energy. And one day is the same as one year.

They're not like an Earth twin. They're more like an Earth cousin because the star is so small and doesn't have much energy. And the stars give off flares a lot. And these Earth cousins, because they're so close to the star to get enough energy to be habitable, the habitable zone is quite close to the star because the stars give off very little energy. And one day is the same as one year.

They rotate one time for every time they orbit. Our moon actually does that because we see the same face of the moon at all times. So one of these earth cousins, what it means is that their star, which is their sun, is actually the same place in the sky at all times. So on that planet, you know, you would live where it's always day, or maybe you would live where it's always nighttime.

They rotate one time for every time they orbit. Our moon actually does that because we see the same face of the moon at all times. So one of these earth cousins, what it means is that their star, which is their sun, is actually the same place in the sky at all times. So on that planet, you know, you would live where it's always day, or maybe you would live where it's always nighttime.

It's a very different type of world. So today we're studying these earth cousins because we can. They're what nature provided that our telescopes can do. But what I want to do, what I and a growing number of people see as our destiny really is to find the earth twin, not the cousin, it's the twin. That would like be you finding your cousin.

It's a very different type of world. So today we're studying these earth cousins because we can. They're what nature provided that our telescopes can do. But what I want to do, what I and a growing number of people see as our destiny really is to find the earth twin, not the cousin, it's the twin. That would like be you finding your cousin.

versus, wow, once in a while someone finds out they've got an identical twin. It's like that. We want to do that. And to find the Earth twin, we have to go above the blurring effects of Earth's atmosphere and have a special kind of space telescope, one that has a way to block out the star light entirely so we can find planets directly.

versus, wow, once in a while someone finds out they've got an identical twin. It's like that. We want to do that. And to find the Earth twin, we have to go above the blurring effects of Earth's atmosphere and have a special kind of space telescope, one that has a way to block out the star light entirely so we can find planets directly.

The method we talked about when the planet goes in front of the star is That's indirect. We don't see light coming from the planet. We see light the planet's blocking. And this going to space and blocking out the starlight is incredibly hard. It's literally at the edges of what we're able to do, but we think we know how to do it.

The method we talked about when the planet goes in front of the star is That's indirect. We don't see light coming from the planet. We see light the planet's blocking. And this going to space and blocking out the starlight is incredibly hard. It's literally at the edges of what we're able to do, but we think we know how to do it.

Ultimately, we don't know. People do like to speculate that life there to withstand all that gravity probably has to be closer to the ground with giant legs. This sounds pretty scary, but like a cockroach with elephant legs. Because cockroaches look so light and they have those tiny legs, you'd have to have big legs and be close to the ground, most likely.

Ultimately, we don't know. People do like to speculate that life there to withstand all that gravity probably has to be closer to the ground with giant legs. This sounds pretty scary, but like a cockroach with elephant legs. Because cockroaches look so light and they have those tiny legs, you'd have to have big legs and be close to the ground, most likely.

You know, sometimes we don't know. We definitely have speculated about this for fun. But one thing in a massive atmosphere, it might block a lot of the sunlight or at least dim it quite a lot. So we love to imagine birds with big wings that also can capture light. So imagine like a cross between a plant and a bird.

You know, sometimes we don't know. We definitely have speculated about this for fun. But one thing in a massive atmosphere, it might block a lot of the sunlight or at least dim it quite a lot. So we love to imagine birds with big wings that also can capture light. So imagine like a cross between a plant and a bird.

Maybe to get the light for photosynthesis, perhaps the life has to get really high up. And the only way they can do that is flying.

Maybe to get the light for photosynthesis, perhaps the life has to get really high up. And the only way they can do that is flying.