The BEST episodes of Space's Deepest Secrets

Every episode of Space's Deepest Secrets ever, ranked from best to worst by thousands of votes from fans of the show. The best episodes of Space's Deepest Secrets!

The stories of deep-space explorers who are risking their careers, and even their lives, to lead humanity to worlds yet to be seen.

Last Updated: 11/10/2024Network: Science ChannelStatus: Ended

8.71

7 votes

#1 - Quest for the First Star

Season 1 - Episode 8 - Aired 6/14/2016

The search for the first stars of the universe.

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8.14

7 votes

#2 - Attack of the Space Junk

Season 1 - Episode 7 - Aired 6/7/2016

The efforts of the U.S. government and others to combat the threat posed by space junk, which could derail the future of space travel if left unchecked.

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8.13

15 votes

#3 - Mission to the Red Planet

Season 4 - Episode 2 - Aired 5/22/2018

The latest science shows what it would take to build colonies on Mars and why human colonization of the Red Planet may take place in the not-too-distant future.

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8.00

19 votes

#4 - Journey to Alien Earths

Season 4 - Episode 4 - Aired 6/5/2018

New discoveries of alien earths reveal vital clues in finding extraterrestrial life. Using the latest science and technology, experts reveal the strange landscapes and oceans of these distant worlds.

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8.00

4 votes

#5 - Pluto's Strange Secrets

Season 4 - Episode 10 - Aired 10/14/2018

NASA's mission to Pluto gathered the first close-up pictures of this strange and distant world, and now, new discoveries and the latest science reveal the secrets of its alien features, which could point to extraterrestrial life.

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8.00

12 votes

#6 - Mars: The Next Frontier

Season 4 - Episode 7 - Aired 6/26/2018

Modern day explorers are competing in a new space race to send the first people to Mars.

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7.94

129 votes

#7 - The Universe's Greatest Hits

Season 1 - Episode 1 - Aired 4/26/2016

From the mission that saw Pluto for the first time to the Mars rovers, a new breed of explorers are risking their careers, and even their lives, to lead humanity to worlds we have never seen and tackle the mysteries of life itself.

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7.93

15 votes

#8 - Mystery of the Alien Megastructure

Season 5 - Episode 2 - Aired 10/22/2018

A mysterious star hundreds of light years away might hold the hard evidence of extraterrestrial life, as experts speculate that its bizarre behavior points to proof of a massive alien-made megastructure.

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7.88

25 votes

#9 - Dark Secrets of the Solar System

Season 6 - Episode 5 - Aired 4/16/2019

New evidence is rewriting the history of our solar system, and using the latest discoveries and cutting-edge tech, experts are investigating if our cosmic neighborhood once featured oversized alien Earths and a second Sun.

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7.88

25 votes

#10 - Pluto: Back From The Dead

Season 7 - Episode 1 - Aired 9/8/2020

A spacecraft captures the first close-up images of the dwarf planet Pluto.

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7.86

14 votes

#11 - Journey to Saturn's Rings

Season 5 - Episode 3 - Aired 10/29/2018

New discoveries change everything known about Saturn's rings, revealing that they're newer and more mysterious than ever imagined, and that some day soon, they might disappear forever.

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7.83

54 votes

#12 - The Plot Against Gravity

Season 1 - Episode 6 - Aired 5/31/2016

The story of how a large aerospace company, BAE Systems, began a secret project to counter the force of gravity while NASA simultaneously ran a similar ‘Breakthrough Propulsion Physics’ program.

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7.83

12 votes

#13 - Secrets of the Asteroids

Season 8 - Episode 6 - Aired 5/5/2021

One of NASA's most ambitious missions is investigating an asteroid in more detail than ever before, revealing how space rocks can kick-start life on other planets and how they could possibly hold answers to the secrets of the Solar System

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7.82

28 votes

#14 - Secret History of the Solar System

Season 1 - Episode 11 - Aired 8/6/2016

The discovery of exoplanets pushes scientists to reexamine the origin of the Solar System; the evidence infers a tale of unrestrained collisions and chaos.

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7.82

22 votes

#15 - Secret History of the Juno Mission

Season 4 - Episode 8 - Aired 7/10/2018

NASA’s Juno mission explored Jupiter, and its images reveal the gas giant’s deepest secrets.

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7.82

55 votes

#16 - NASA's Greatest Moments

Season 2 - Episode 1 - Aired 4/11/2017

Counting down the greatest moments in NASA's nearly sixty year history, revealing the incredible stories behind the missions and discoveries that have remade our understanding of the Final Frontier

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7.81

21 votes

#17 - The Time Travel Enigma

Season 4 - Episode 1 - Aired 5/15/2018

Scientists may be on the verge of cracking time travel, one of the universe's greatest puzzles, due to new discoveries in space and theoretical physics.

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7.81

47 votes

#18 - Secret History of the Voyager Mission

Season 1 - Episode 5 - Aired 5/24/2016

Thirty-five years after leaving Earth, the Voyager spacecraft is going to leave the Solar System to tell the incredible story of a mission that was only supposed to last five years but is still going today.

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7.78

27 votes

#19 - Hunt for the Missing Black Holes

Season 6 - Episode 8 - Aired 5/7/2019

New discoveries might finally reveal how supermassive black holes are made, and using the latest technology, experts are on the verge of understanding how these monsters grow and how they affect life on our planet.

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7.76

25 votes

#20 - Inside a Monster Black Hole

Season 1 - Episode 14 - Aired 8/27/2016

Inside the supermassive black hole that sits in the middle of our galaxy.

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7.75

20 votes

#21 - Asteroid Apocalypse

Season 6 - Episode 10 - Aired 5/21/2019

New discoveries reveal the apocalyptic consequences of an asteroid strike, and using cutting-edge science, experts are racing to develop tech that can destroy these deadly killers before they unleash Armageddon.

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7.73

52 votes

#22 - Alien Oceans

Season 1 - Episode 4 - Aired 5/17/2016

A soaring quest through the solar system’s exotic and hidden water realms, from the deep seas below the icy crust of Europa to the vast prehistoric oceans that once existed on Mars billions of years ago.

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7.73

22 votes

#23 - Hunt for the Mars Aliens

Season 7 - Episode 2 - Aired 9/15/2020

NASA's brand-new Mars rover is on the hunt for alien life, and with the help of cutting-edge engineering, scientists embark on a search for fossilized remains, which might prove the Red Planet was once home to a vast ocean and extraterrestrial life.

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7.72

18 votes

#24 - New Race to the Moon

Season 4 - Episode 6 - Aired 6/19/2018

New discoveries reveal that our Moon could be the next home for human life, triggering a new international space race to make it the home of humanity’s first space colony.

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7.72

18 votes

#25 - Dark Origins of the Moon

Season 5 - Episode 1 - Aired 10/15/2018

New discoveries reveal that everything known about the moon could be wrong; investigators race to understand the mysteries of its dark and violent past.

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