Our Window to the Stars

01We all know what it's like to wander outside and look up at the night sky.

02On a clear night, when you can see all of the stars perfectly, it's so easy to feel small.

03It makes you wonder, what's out there, beyond what we can see?

04The Hubble Space Telescope has helped us answer that question over the last 30 years, revealing that reality is often stranger than fiction.

05We've seen the births and deaths of stars, and we've found answers to questions we'd never even thought to ask before.

06We've learned all of this in incredible detail, by looking back in time.

07Hubble is like a time machine in the sense that we can look farther and farther out into the universe, at these fainter and fainter, more distant galaxies.

08And by doing that, we're really looking back in time, because it has taken time for that light to get to us from these stars and galaxies.

09That's Jennifer Wiseman.

10She's the senior project scientist for Hubble, and says that the telescope is achieving more than scientists originally expected.

11Hubble has recently contributed to the determination that the expansion of the universe is, in fact, accelerating.

12That was unexpected.

13Hubble has become the pioneering telescope in analyzing the atmospheres of exoplanets.

14Hubble has found the likely presence of water in moons around other planets, using interesting, innovative techniques.

15That was really not something Hubble was originally designed for.

16So we're using Hubble now for kinds of science we did not originally anticipate.

17And after all this time, the discoveries we get from Hubble every day are still knocking us back, telling us more about the nature of our universe and its origins.

18But Hubble's journey to the stars was a difficult one.

19So how did it succeed?

20Welcome to NASA's Curious Universe.

21I'm Patti Boyd, and in this episode, we're exploring a truly iconic NASA mission, the Hubble Space Telescope, our window to the stars.

22This is the story of how NASA put a telescope in space.

23Decades before the Hubble Space Telescope was even a possibility, the idea of looking beyond our own atmosphere was at the forefront of astronomy.

24Back then, most astronomers believed that the universe consisted of just one galaxy, our own Milky Way.

25Then, Edwin Hubble came along and changed everything.

26From a mountaintop near Los Angeles, he peered up at the night sky with a ground-based telescope, the Hooker Telescope, which at the time was the largest one in the world.

27That's when he spotted something amazing.

28The fuzzy objects he noticed in our sky were actually other galaxies.

29And most of these galaxies he spotted looked like they were moving away from each other.

30Edwin Hubble was one of the pioneers that determined that our universe is, in fact, expanding.

31galaxies seemed to be moving apart from each other along with that stretching of space.

32But we couldn't quite discern the rate of that expansion.

33It's a very difficult measurement.

34So the Hubble Space Telescope was able to contribute to a really higher precision measurement of that expansion rate by measuring more carefully the distances of these galaxies and correlating that with other measurements of their apparent velocities and giving us an expansion rate that was much more refined than anything ever before.

35Edwin's discoveries made scientists wonder.

36If we could see all that coming from a ground-based telescope, what would happen if we sent one above our murky atmosphere?

37German scientist Hermann Oberth dreamed of what we might learn.

38If we could look at the heavens with an astronomical telescope in orbit, unhindered by the shielding sea of atmosphere that blankets the Earth, think of the discoveries we would make, the clear vision of the universe we would have.

39Echoing Oberth's vision, astronomer Lyman Spitzer outlined the details for how to make it all work in an academic paper that would really set the stage for Hubble.

40NASA set out on an adventure to place a telescope in space.

41This telescope would discover things that would revolutionize the way we think of our place in space.

42Here's what the great astronomer Carl Sagan had to say about this bold experiment.

43Space Telescope is, in a way, a little like Galileo's first telescope.

44Wherever Galileo pointed his telescope, he made major new discoveries.

45Look at the moon, you find mountains and craters.

46Look at Saturn, you find rings.

47Look at the Milky Way, you find it is littered and composed of stars.

48Every one of these discoveries, things that people had not known before.

49I think it's going to be very similar with the space telescope.

50It will illuminate celestial objects that we know about.

51It will discover celestial objects never before guessed.

52It will provide insights into the most important questions such as stellar evolution, such as the search for planets going around other stars, and the grandest cosmological questions of the origin, nature, and fate of the universe.

53The space telescope is a kind of grand intellectual adventure for all of us, which will cast light not just on the cosmos, but also on ourselves.

54The telescope was built at Lockheed Martin in California, with NASA's Marshall Space Flight Center overseeing the telescope's construction.

55It was named after Edwin Hubble, who paved the way for grand discovery.

56But actually getting a telescope the size of a school bus into space is difficult.

57As you might imagine.

58That's where the Space Shuttle Discovery comes in.

59NASA's space shuttles were designed to carry and deploy spacecraft like Hubble.

60With the Space Shuttle Discovery, NASA astronauts would deploy Hubble at the edge of space, in low-Earth orbit, and return safely to Earth.

61NASA designed the telescope to fit snugly inside Shuttle Discovery, which carried and released this precious cargo into space.

62The shuttle Discovery poised at Cape Canaveral for a launch tomorrow morning.

63It may be the most ambitious and eagerly awaited mission in the history of the shuttle program.

64Onboard a giant telescope that will redefine our view of the universe.

65When it launched in 1990, NASA's Hubble Space Telescope was only designed to last 15 years.

66In 2020, the telescope celebrates its 30th birthday, and Hubble is still as powerful as ever.

67Hubble makes discoveries 24 hours a day.

68It's up there orbiting the Earth.

69And it goes around the Earth about once every 90 minutes.

70And so, you know...

71That's Michelle Thaller, an astronomer and science communicator at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

72Goddard is home to Hubble's mission control.

73The Hubble Space Telescope is something that just changed everything.

74I think people now have this view, you know, what does space look like?

75And they don't even realize that what they're thinking of is something that Hubble images brought to our culture, to our imagination.

76She's right.

77When you close your eyes and imagine space, you probably picture stars, beautiful colors, and a sheer vastness.

78The images that pop into your head are probably star-studded and full of the colorful clouds of nebulas.

79That's because the pictures taken by the Hubble Space Telescope are the clearest and closest we've ever come to looking at our universe.

80They've fundamentally shaped how we think of space.

81And from space, Hubble can see a lot.

82Here's one way of looking at it.

83Imagine going to a piano concert, and the musician sits down and can only play three notes around middle C.

84That's the amount of light we can see here on Earth.

85Then there's a whole spectrum of light our eyes aren't sensitive to.

86And that's where Hubble comes in.

87Hubble can see in multiple wavelengths of light, like infrared and ultraviolet.

88So Hubble's view would sound a lot more like a symphony.

89NASA made a huge push in the years leading up to Hubble's launch to promote the revolutionary telescope's efforts.

90NASA promised the public that this project would lead to important discoveries and answers.

91After all, this was the culmination of decades of work and research, not to mention the financial and emotional investments riding on this mission.

92On April 24, 1990, the telescope launched.

93Three, two, one, and liftoff of the space shuttle Discovery with the Hubble Space Telescope, our window on the universe.

94Back on Earth, Mission Control monitored the deployment carefully.

95They knew what was at stake.

96And this is Hubble Telescope Control in Greenbelt.

97We have been given the go-ahead to begin commanding release of the forward latches, which hold the solar arrays in place during launch.

98When the Discovery crew set out to deploy the telescope, they were under a lot of pressure.

99After all, Hubble was set to be the greatest astronomical advancement since Galileo picked up a telescope.

100But something went wrong.

101Of course, when Hubble finally got up and everybody was really excited, there was this amazing sense of deflation.

102When they opened up the telescope, light went through it, and they realized the images were out of focus.

103And they were out of focus because the curvature of the mirror was wrong.

104So, I mean, this was just an incredible mistake.

105I mean, people have been making very accurate telescope mirrors for a long time.

106And the fact that all of a sudden, up in space, what were we going to do now?

107You know, this incredibly valuable instrument was launched, and there was this tremendous problem.

108The first pictures that NASA saw here on Earth were fuzzy and distorted.

109And it was all because of an incredibly small, almost undetectable aberration, a tiny error from when the mirror was constructed.

110Hubble's vision was blurry.

111But the telescope was still technically doing its job, at least as far as astronomers like Michelle were concerned.

112The spectrographs still worked just fine.

113The images were out of focus.

114But all of the data, you know, the really detailed data about the universe was still coming in through these spectroscopic instruments.

115So for people specifically doing my science, Hubble started working beautifully.

116We were making incredible discoveries.

117But of course we wanted to get those clear images, to see the universe without the distortions of the atmosphere, to see it beautifully, beautifully clear.

118From the beginning, Hubble was designed to work hand-in-hand with the space shuttle program.

119NASA had anticipated that Hubble would need to be modified, and expected to send astronauts to do so in the coming years.

120What was not anticipated was that the first images coming from the Hubble Space Telescope were quite disappointing.

121There was obviously a problem.

122...telescope system optics.

123The conclusion we've come to from that is that there's a significant spherical aberration appears to be present in the optics, in the optical telescope.

124The mirror on Hubble had been ground beautifully, but to a slightly incorrect formula, and this had not been caught in testing.

125This incredible idea was raised, you know, why don't we fix it?

126And then this is one of the grand adventures of NASA.

127NASA set out on a daring rescue mission to save the Hubble Space Telescope.

128They came up with a very insightful solution.

129Basically, in some sense it's been described as putting glasses on Hubble.

130These glasses were actually an instrument which was designed to correct Hubble's flaw.

131A team of astronauts were prepared to service the telescope in space.

132Hello, Houston.

133We are inspired.

134We are ready.

135Let's go fix this thing.

136Sounds like a good plan, Endeavor.

137Good morning.

138They made an instrument that actually corrected the light before it went into the cameras, took out the wrong curvature.

139Okay, I'm in one inch.

140You're in one inch.

141And I have it.

142You have it?

143Yes, I have it.

144Okay, I'm going to let go.

145All of a sudden things snapped into just beautiful, beautiful focus.

146Everything was gorgeous.

147So it is one of the most amazing happy endings in the history of science, in the history of technology.

148Hubble's servicing missions didn't stop with its initial rescue.

149Over the years, Hubble has been serviced multiple times.

150John Grunsfeld is one of the astronauts who helped keep Hubble in top shape.

151For me as an astronomer, going out in a spacesuit and working on the Hubble is just the ultimate experience.

152There's nothing cooler.

153Hubble is an incredible icon of science.

154And so to me, it was the holy grail of being an astronaut.

155John worked on three repair missions to the telescope, earning the nickname Hubble's Keeper from publications like the New York Times.

156I was expecting, you know, the wonders of space and the beauty of the Earth.

157What surprised me the most was that I kind of discovered my humanity.

158You know, that being in a tight crew, working together as a team with hundreds, thousands of folks on the ground, that there's really nothing, I think, that humans can't achieve if we work together as a team.

159And if we have good challenges, things that are worth doing, we can do almost anything.

160We know so much about our universe now because of people like John, people who were watchful stewards of the telescope and who dedicated themselves to its success.

161Hubble has lasted a lot longer than we expected.

162We thought Hubble might last 10 or 15 years if we were lucky.

163But thanks to the series of astronaut servicing missions over the years, the telescope has been refreshed over and over again with repaired instruments and new batteries and gyroscopes and things like that, refreshed new instruments as well.

164And that has made the telescope basically brand new, more or less, every time we've done a servicing mission, and that's kept it at the forefront of scientific discovery.

165NASA Jet Propulsion Laboratory, California Institute of Technology To get a look at the outstanding imagery from the Hubble Space Telescope, visit nasa.gov slash hubble.

166You can also follow the telescope on social media at nasahubble.

167This is NASA's Curious Universe.

168The Curious Universe team includes Elizabeth Tamme and Michaela Sosby.

169Our executive producer is Katie Atkinson.

170Special thanks to the Hubble Space Telescope team.

171If you're enjoying Curious Universe, consider leaving a review on your podcast app or tweeting about the show at NASA.

172And in the next episode, astronaut Nick Haig takes us to an underwater training ground.

173We'll be right back.

174We'll be right back.

175We'll be right back.

176We'll be right back.

177We'll be right back.