Webb Space Telescope: Into the Unknown

01I think the Webb Telescope will attract the attention of everyone.

02Number one, because it's a huge technical thing to do.

03And number two, because we're going to discover things nobody ever knew about.

04And I suppose number three is we'll make pretty pictures.

05But I think the great discoveries that really fit into our history of ourselves.

06How did we get here from the Big Bang story, the expanding universe?

07Galaxies growing, black holes growing, stars blowing up, new star systems being produced, planets growing around those little stars.

08We might also get some big surprises, too.

09I like to think that our imagination has been limited all along, and we probably still find something we never thought of.

10I think we will.

11This is NASA's Curious Universe.

12Our universe is a wild and wonderful place.

13I'm Patti Boyd, and in this podcast, NASA is your tour guide.

14In just a few weeks, the world's most powerful and complex space telescope will begin a journey like no other.

15From a million miles away, the James Webb Space Telescope will gaze out into our solar system and beyond.

16It will appear back in time 13.5 billion years to when our universe was merely a toddler.

17We want to understand how, out of a hot soup of chaos, the first stars and galaxies took shape.

18The James Webb Space Telescope will look at stars and planets near and far, to search for clues to our origins and to the question everyone wants to know.

19Are we alone?

20The James Webb Space Telescope is such a fascinating mission that we are dedicating four episodes of this podcast to learning about its science, engineering, people and launch.

21This is part one, focusing on science.

22I'm John Mather.

23I'm the James Webb Space Telescope Senior Project Scientist, which means that I work with scientists and engineers from day one.

24John is a scientist at Goddard Space Flight Center.

25We introduced him briefly in season two.

26He holds a Nobel Prize for his work on the Cosmic Background Explorer, a satellite that showed us the first baby pictures of the universe.

27I thought, well, we're never going to do anything exciting again like that.

28And then I got a phone call.

29NASA Headquarters Ed Weiler called up and left a message saying, we're going to start a study of this new telescope.

30Do you want to work on it?

31And I thought, I've never heard of anything so exciting before.

32I'm going to do that.

33Immediately, I abandoned all other ideas and said yes.

34That was October 1995.

35I remember that it was really fun getting started.

36The first day that we had a sketch by a person who knew how to draw on the big whiteboard that says it could look like this.

37And you know, it pretty much looks like what that man drew.

38Except we had a lot of different ideas about how it would get there.

39But we knew we needed to build something bigger and more powerful than Hubble.

40The Hubble Space Telescope launched in 1990 and has changed our understanding of the universe in many ways in the last three decades.

41But even in the early days of Hubble, a committee of scientists was thinking about what would come next.

42They called it the Next Generation Space Telescope.

43So they wanted two things, actually.

44One is another more powerful telescope that could do infrared astronomy, which the Hubble could not do.

45And they also said, by the way, we also want to know about planets around other stars.

46We were just getting hints that there were some of them out there, because a few had been found in that very year.

47And so they said, please figure out how to do that, NASA.

48So NASA has done both.

49We'll talk more about the great things that Webb will discover and investigate in a moment.

50But first, we need to talk about light.

51One thing that's not intuitive to humans is that light actually travels.

52Just like if you were to get in the car, you wouldn't be at your friend's house instantaneously.

53It takes you time to get there.

54That's Alex Lockwood at the Space Telescope Science Institute in Baltimore, where she is the project scientist for web science communication.

55Light has a speed limit of 186,000 miles per second.

56Keep that in mind as Alex explains how looking out into the universe is like looking back in time.

57When light is created from the sun, it takes eight minutes of that light wave to move, just like a regular wave does, through space and hit the Earth.

58We call that eight light minutes.

59So basically, the closer something is, the newer it is.

60The further away it is, because the light that's hitting our eyes now is the light that has traveled for that amount of time.

61That light is actually a preserved fossil of what that thing looked like billions of years ago.

62To become the groundbreaking science powerhouse that scientists envisioned, Webb would need to sense a special kind of light called infrared.

63Infrared light is really good for looking at distant objects in the universe, because it lets us see through cosmic dust.

64There's a lot of dust out in the universe, just like probably under your bed and mine.

65Okay, it's not literally the same kind of dust, but you get the picture.

66And it blocks our view of things like stars that are being born.

67Dusty environments are wonderful for creating things.

68That's how new stars are formed.

69But if you can't see through the dust, you don't know what's going on as that star is being born.

70And that's a very, very interesting environment and tells us about our own origins, because after the star is born, planets are formed and all of the evolution that leads to where we are today.

71So, with James Webb, we'll be able to see through the dust out in the universe into these environments where stars and planets are forming and really get insights into the origin of planetary systems that we've never had before.

72Here's something even weirder.

73The light from the distant parts of the universe gets stretched out as it travels for billions and billions of years.

74So short wavelengths become longer as they travel.

75If a galaxy billions of light years away is emitting visible light, it may reach us in the infrared, which is a longer wavelength.

76That's because empty space itself is stretching out faster and faster as we speak.

77Scientists are so perplexed about why this happens, they call the mysterious engine of this expansion dark energy.

78But that's a topic for another episode.

79John's Nobel Prize winning research helped confirm that our universe began in a rapid expansion known as the Big Bang.

80The Webb telescope won't look quite that far back, but it will look at a period of the early universe no one has ever seen before.

81If you ask a bunch of astrophysicists what they're most excited to learn from Webb, chances are they'll all have different answers, since Webb is going to look at so many different kinds of objects.

82But when scientists began planning this complicated mission more than 25 years ago, they had one goal in mind.

83To see where did the first galaxies come from.

84Some of the very first galaxies that were born after the Big Bang.

85The first galaxies to form.

86The first galaxies in the universe.

87The very beginning.

88The first galaxies.

89The assembly of the first galaxies.

90It's a little hard to keep track of all the different structures in the universe.

91So let's review what a galaxy actually is.

92Our solar system consists of our sun and all of the planets, asteroids and comets that orbit it, thanks to the powerful gravity of our host star.

93But the sun doesn't sit still.

94It's actually on a really long orbit around the center of what we call a galaxy, the Milky Way, which contains about 100 billion stars.

95Here's Alex again.

96If you look at our own Milky Way, we have a large, reasonably large spiral galaxy that has a distinct shape similar to what we can see in the whirlpool galaxy, for example.

97You have these beautiful spiral arms and what we see is a lot of structure.

98And so at some point, the first galaxies that were just kind of clumps, small clumps of stars over billions of years, those galaxies converged with each other.

99We believe this spiral shape is a natural progression out of galaxy evolution and mergers.

100Studying the first galaxies will teach us about how the Milky Way evolved.

101We're hoping that if we understand what the earliest galaxies looked like, and we can look at galaxies nearby us that represent more evolved galaxies, that we can put together the picture of what does a typical galaxy life look like.

102And we can guess that these earliest galaxies that we're seeing might look something like the Milky Way does today.

103At the center of our galaxy is a supermassive black hole called Sagittarius A star, weighing the equivalent of about 4 million suns.

104In fact, there's a supermassive black hole at the center of nearly every galaxy.

105But today we have no idea how they got to be there and grow so big so fast.

106It's a chicken and egg problem that Webb may help solve.

107I'm hoping that we find out which came first, the black holes or the galaxies.

108It might be that the Big Bang made the black holes directly.

109It might be that the first generations of stars led directly to black holes and that they just disappeared.

110We have some evidence that that can happen, that a star can just collapse and turn into a black hole.

111We now know that black holes can meet each other and combine and make bigger black holes.

112This is actually pretty common, but nobody knows how that ever got started.

113So we'd like to know about that.

114Somehow, the galaxy as big as ours, the Milky Way, has several millions worth of stars, all collapsed into one gigantic black hole in the middle.

115And some galaxies are even bigger.

116They have billions of stars all squeezed into one tiny black hole.

117So this is a huge mystery, and I think we'll find out.

118That's just awe-inspiring when you think about it.

119Not everyone is most excited about Webb's revelations about the first galaxies.

120There's observations of Mars, Jupiter, Saturn's rings, Uranus and Neptune, Pluto, comets.

121What have I left out?

122That's Heidi Hamill, the Vice President of the Association of Universities for Research in Astronomy, or Aura.

123She's been involved in some truly epic moments in solar system exploration.

124When Heidi started out in graduate school, she focused on astrophysics.

125You know, all that stuff about how stars and galaxies work.

126But when it came time to focus on a dissertation, she turned her gaze to giant planets that no one knew a lot about.

127And I'm like, you know what?

128We know so little about Uranus and Neptune that anything that I learn will be expanding the envelope of knowledge.

129Heidi had already established herself as a world expert in this mysterious blue planet by the time Voyager 2 took the first ever close-up images of Neptune in 1989.

130Some telescopes have a wide field of view and show us a broad perspective of what's out there, finding new planets, galaxies and more.

131Webb, on the other hand, will look in closer detail at cosmic objects that scientists have already located to get to know them better than ever before.

132It's sort of like we have a puzzle with one-tenth of the pieces we need to put the puzzle together.

133James Webb Space Telescope is going to add more pieces to this puzzle.

134It's going to help us, particularly studying the dynamics of the atmosphere and the chemistry of the atmosphere.

135Some of the objects that Webb will study have already received visits from other spacecraft, or will in the near future.

136But they're still worth looking at with our shiny new observatory.

137Here on Earth, wherever we find water, we tend to find life.

138That's why scientists are especially interested in finding water on other planetary bodies.

139Jupiter's moon Europa and Saturn's moon Enceladus are both covered in ice, but are thought to have deep oceans underneath.

140Webb will be looking closely at Europa and Enceladus to see if there's evidence of water spewing out.

141Webb has lessons to teach us even about Mars, which has orbiters, rovers, a lander and even a helicopter sending back new data every day.

142That's because every time we send a probe into space, it can't do everything.

143It will have sensors for specific kinds of light, and an itinerary that focuses only on particular objects or locations.

144To truly understand worlds beyond our own, we need to look at them from multiple perspectives and in many different ways.

145It's like we have an astronomy toolbox that has many different kinds of tools in it.

146And you need all the tools.

147You can't just have a screwdriver or a wrench, you know.

148You can do good things with screwdrivers and wrenches, but you don't do the same things with screwdrivers and wrenches.

149There's one more way that Webb is going to change the way we think about the universe.

150One that hadn't yet taken shape when John and his colleagues were envisioning the telescope in the 1990s.

151Back when Webb was just an idea, astronomers started discovering planets beyond our solar system, or exoplanets.

152First, they found planets orbiting a dead star called a pulsar in 1992.

153Then, in 1995, a different group of astronomers spotted the signatures of planets orbiting 51 Pegasi, a sun-like star 50 light-years away.

154While Webb scientists were planning a mission focused on the first galaxies of the universe, the list of known exoplanets started growing and growing.

155There are many, many more planets out there than we ever dreamed.

156Most of the stars had planets.

157A lot of them had more than one.

158And there are even a lot of loose planets that got left, expelled from their homes and are wandering around in between the stars.

159We'll find out something about all of this.

160And I think we'll be amazed.

161And it turned out, an infrared observatory would be perfect for zooming in on the atmospheres of these mysterious worlds.

162With more and more planets being discovered, scientists started making lists of the ones best suited to follow up on with Webb.

163Now there's a fascinating and diverse collection of planets on the schedule for Webb to look at in finer detail than ever before.

164Especially when it comes to the atmospheres of these planets.

165It's the atmospheres that are going to tell us whether those planets could be habitable.

166Here's Alex Lockwood again.

167You step outside on a hot summer day, especially in the south, and you know that there's water vapor in the air.

168It's very humid, but you can't see it.

169If you put on your infrared goggles, you'd actually be able to see the emission of water vapor in the air.

170We can do that for other planets.

171So in fact, when I was in school, I discovered water vapor on a planet using infrared wavelengths.

172That's right.

173She discovered water vapor on a planet.

174It was cool.

175It was really cool.

176But we can't see that with Hubble.

177It's only in these longer wavelengths do some of the really, really interesting molecules.

178And molecules that are interesting, not only even of themselves, like water is really cool, but has implications for any kind of, you know, life-bearing signatures.

179So water vapor, carbon dioxide, carbon monoxide, methane, these are all molecules that we can study in the infrared.

180The story of how Webb added exoplanets to its science goals speaks to my own life, too.

181I became the NASA Headquarters Program Scientist for the Kepler Space Telescope, which would go on to discover more than 2,600 exoplanets and show us that there are more planets than stars in our galaxy.

182And now I'm the project scientist for TESS, a satellite that has already discovered 25 planets that Webb will study in further detail in its first year of science.

183What keeps me going in this field is a lifelong curiosity about the big questions.

184Like, are we alone?

185Is Earth common?

186Do we live in a really rare place?

187Generations have asked those questions, but this is the only time in history where we've actually had the ability to answer those questions with examples of planets around other stars.

188With Webb, we're just walking in the door to learn so much more about our place on Earth, in the Milky Way, and in the universe.

189Next time on NASA's Curious Universe.

190You have the opportunity to combine science with art.

191There's an artistic feature of James Webb that can't go unnoticed.

192I would hope that individuals can see something that took so much time and that also is artistically creative and that so many minds have gone into.

193That individuals are inspired to continue to pursue whatever, you know, career path they're going after, and kind of see how it blends into the world of space.

194This is NASA's Curious Universe.

195This episode was written and produced by Katie Atkinson, Liz Landau, and Christina Dana.

196The Curious Universe team includes Maddie Arnold and Michaela Sosby, with support from Elissa Fielding.

197Special thanks to Ryland Hegey, Amber Strawn, Paul Geithner, Eric Smith, Natasha Pinole, Elise Fisher, Laura Betts, and the James Webb Space Telescope team.

198If you liked this episode, please let us know by leaving us a review, tweeting about the show at NASA, and sharing with a friend.

199Still curious about NASA?

200You can send us questions about this episode or a previous one, and we'll try to track down the answers.

201You can email a voice recording or send a written note to nasa-curiousuniverse at mail.nasa.gov.

202Go to nasa.gov slash curiousuniverse for more information.