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How Do We Measure the Distance to Stars?

01:49

Do Cosmic Rays Spark Lightning? - Instant Egghead

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How Do Earthquake Warning Systems Work?

02:20

Comets versus Asteroids - Instant Egghead

03:08

What Does the Universe Sound Like? - Instant Egghead

01:56

Is Our Universe a Hologram? - Instant Egghead

02:07

Who Owns Outer Space? - Instant Egghead

06:12

Cosmos-Mapping Team wins 2017 Breakthrough Prize in Physics

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Neutron Star Collisions Create Gold

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Cassini Says Goodbye

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See Jupiter's Great Red Spot Up Close

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Top Ten Weirdest Things in the Solar System

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TRAPPIST-1 and a Trove of Exoplanets

02:06

Pioneer 10 Meets Jupiter - It Happened in Space #24

02:38

Moon Meeting of Apollo12 and Surveyor 3 - It Happened In Space #23

03:09

Mutiny on Apollo 7 - It Happened in Space #22

02:43

When NASA Lost a Spacecraft Because It Didn't Use Metric - It Happened in Space #21

02:34

Voyager 2's Grand Tour - It Happened in Space #20

02:19

The Pen that Saved Apollo 11 - It Happened in Space #19

03:23

Behind NASA's First Spacewalk - It Happened in Space #18

01:52

Apollo 10's Non-Landing on the Moon - It Happened In Space #17

03:58

The Top 5 Strangest Things Ever Shot Into Space - The Countdown #47

03:52

5 Ways Space Travel Affects the Human Body - The Countdown #46

05:40

How Can Galaxies Move Faster than Lightspeed? - Ask the Experts #25

02:15

Food (and Bacon) on the Moon - It Happened In Space #16

04:12

5 Things Dark Matter Could Be - The Countdown #45

02:29

Apollo 9's Unused Contingency Plan - It Happened In Space #15

04:22

5 Facts about Gravity Waves from the Big Bang - The Countdown #44

04:37

Why Is There Something Instead of Nothing? - Ask the Experts #24

04:16

5 Space Photos that Speak to Our Human Existence - The Countdown #43

03:48

5 Strange Ways to Clean Up Our Space Junk - The Countdown #42

01:56

Apollo and the Saturn IB Rocket - It Happened In Space #14

03:59

5 Everyday Products Developed from NASA Technology - The Countdown #41

03:29

Will Heat from Our Dying Sun Make Mars Habitable? - Ask the Experts #23

03:36

5 Things You Need to Know About Rosetta, the Comet Chaser -- The Countdown #40

02:13

The Return of Apollo 13's Plutonium - It Happened In Space #13

03:40

5 Remarkable Facts About the Northern Lights (Aurora Borealis) - The Countdown #39

04:27

Top 5 Space Stories of 2013! - The Countdown #38

03:50

5 Signs of Life On Mars - The Countdown #37

02:52

Apollo 8's Lunar Christmas - It Happened in Space #12

03:01

5 Things You Should Know About Comet ISON - The Countdown #36

03:19

Asteroid with Six Tails! - The Countdown #35

03:02

Could We Destroy a Black Hole with Antimatter? - Ask the Experts #22

03:19

Gene Cernan's Challenging Spacewalk - It Happened in Space #11

04:16

The Coldest Place in the Universe - The Countdown #34

03:15

BOR-4, the Soviet Space Shuttle Test Bed - It Happened in Space #10

05:54

5 Amazing Exoplanets! - The Countdown #33

05:37

Is The Universe Flat or Curved? - The Countdown #32

06:34

What if Our Galaxy Contained a Powerful Quasar? - Ask the Experts #21

06:04

Voyager Enters Interstellar Space! - The Countdown #31

02:53

When the Soviets Photographed the Surface of Venus - It Happened in Space #9

05:48

Did Life Come From Mars? - The Countdown #30

04:22

Why is The Moon Moving Away From Us? - Ask The Experts #20

05:22

Star Music! - The Countdown #29

03:41

The Lunokhod Rovers - It Happened in Space #7

06:35

Top 5 Places to Look for Alien Life! - The Countdown #28

06:56

Sean Carroll Answers Your Questions - Ask the Experts #19

06:12

Black Hole Devours Cosmic Cloud! - The Countdown #27

02:50

Luna 15 and Apollo 11 - It Happened in Space

06:12

5 Unsolved Space Mysteries! - The Countdown #26