Including results for alien theory 2021.
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Why haven’t we found aliens? A physicist shares the most popular theories. | Brian Cox
12:47
Why haven’t we found aliens? A physicist shares the most popular theories. | Brian Cox
3M viewsSep 29, 2023
YouTubeBig Think
The Evidence For Alien Theories *MARATHON* | Ancient Aliens
2:12:19
The Evidence For Alien Theories *MARATHON* | Ancient Aliens
176.1K views3 months ago
YouTubeHISTORY
Alien Theories You Have to See to Believe | Ancient Aliens | Marathon | History
2:12:17
Alien Theories You Have to See to Believe | Ancient Aliens | Marathon | History
529.1K viewsJun 6, 2025
YouTubeHISTORY
Big Alien Theory: Could Most Aliens Be Bigger Than Us?
40:56
Big Alien Theory: Could Most Aliens Be Bigger Than Us?
112.7K views8 months ago
YouTubeIsaac Arthur
Why Scientists Think Aliens Have Already Visited Earth | Unveiled
9:06
Find in video from 05:00Loeb's Theories and Theories
Why Scientists Think Aliens Have Already Visited Earth | Unveiled
107K viewsSep 3, 2022
YouTubeUnveiled
The most unsettling alien theory
30:26
The most unsettling alien theory
2 months ago
MSNIsaac Arthur
The ancient alien theory sounded possible - until the missing evidence became impossible to ignore
31:07
The ancient alien theory sounded possible - until the missing evidence became impossible to ignore
2 months ago
MSNIsaac Arthur
31:07
The ancient alien theory sounded possible - until the missing evidence became impossible to ignore
2 months ago
MSNIsaac Arthur
30:26
The most unsettling alien theory
2 months ago
MSNIsaac Arthur
20:27
Humans From the Future | Ancient Aliens | History
2.1M viewsMay 8, 2025
YouTubeHISTORY
1:18:32
The NEW Complete Alien Timeline (1979 - 2025)
228K views10 months ago
YouTubeNerdist
23:20
Linda Moulton Howe's BIGGEST Theories Revealed | Ancient Aliens | History
364.9K viewsMay 1, 2025
YouTubeHISTORY
1:16:35
How Close Are We To Finding Alien Life?
566.5K viewsMar 13, 2024
YouTubeWhat If
20:20
The Truth Behind These Unexplained Phenomena | Ancient Aliens
210.2K views5 months ago
YouTubeHISTORY
42:26
The Extraterrestrial Genetic Theory | Ancient Aliens
87.4K views3 months ago
YouTubeHISTORY
8:38
Alien: Earth — Theories That Actually Fit the Timeline
49.5K viewsAug 26, 2025
YouTubeScreenRant
32:32
The Hybrid Theory: Human or Alien? | Ancient Aliens | History
1.1M views11 months ago
YouTubeHISTORY
59:11
Ancient Aliens: TOP UFO MYSTERIES OF 2025 | Part 1
427.2K views10 months ago
YouTubeHISTORY
4:34
The Pentagon’s Mysterious UFO Program (S21) | Ancient Aliens | History
38.9K viewsMay 10, 2025
YouTubeHISTORY
1:03:40
Alien Conspiracy: They Are Here
2.2K views5 months ago
YouTubeExtreme Mysteries
30:49
Alien Theory: Comet 3I/ATLAS Enters Solar System With Unusual Tail Shift | The Breakfast Club
9.2K views11 months ago
YouTubeCNN-News18
48:49
Inside the Mystery of the Greys | Ancient Aliens
1.6M views8 months ago
YouTubeHISTORY
2:05:33
Uncovering the Truth: Giants, Alien Relics & The Human Experiment *Marathon* | Ancient Aliens
709.9K viewsAug 22, 2025
YouTubeHISTORY
6:07
Ancient Aliens: The Shocking Theory Behind the Gods (S1)
26.2K views5 months ago
YouTubeHISTORY
1:18:30
Brian Cox: Why black holes could hold the secret to time and space | Full Interview
5.1M viewsJul 11, 2025
YouTubeBig Think
34:00
Inside Look At Area 51 *New Theories Revealed!* | Ancient Aliens | History
10.6M viewsApr 22, 2025
YouTubeHISTORY
15:12
Michael Masters' Theory That Aliens Are Time Travelers
1.4M views10 months ago
YouTubeJRE Clips
33:04
Outer Space’s Most Baffling Mysteries | Ancient Aliens | History
837.8K viewsMar 4, 2025
YouTubeHISTORY
10:07
Are We Alone in the Universe? We’re Close to Finding Out | Lisa Kaltenegger | TED
200.9K viewsFeb 13, 2025
YouTubeTED
20:43
Top 20 Alien Conspiracy Theories
97.3K viewsNov 14, 2024
YouTubeWatchMojo.com
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