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These Ancient Stones Helped Track the Seasons

Along the river Gambia in Senegal, there are more than a thousand stone circles. The people who placed these stones would have observed how the locations of sunrise and sunset varied over the year.
Clip Season 50 Episode 2 Length 02:57 Premiere: 02/08/23

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Season 50 Episodes

Your Brain: Who's in Control?
S50 E10 Length 53:31 Premiere Date 05/24/23

Your Brain: Perception Deception
S50 E9 Length 53:30 Premiere Date 05/17/23

Hidden Volcano Abyss
S50 E8 Length 53:20 Premiere Date 05/10/23

Saving the Right Whale
S50 E7 Length 53:31 Premiere Date 05/03/23

Chasing Carbon Zero
S50 E6 Length 53:31 Premiere Date 04/26/23

Weathering the Future
S50 E5 Length 53:31 Premiere Date 04/12/23

New Eye on the Universe
S50 E4 Length 53:31 Premiere Date 02/22/23

Ancient Builders of the Amazon
S50 E3 Length 53:22 Premiere Date 02/15/23

Star Chasers of Senegal
S50 E2 Length 53:20 Premiere Date 02/08/23

London Super Tunnel
S50 E1 Length 53:20 Premiere Date 02/01/23

Could Whale Poop Help Cool the Planet?
Clip Length 02:43 Premiere Date 05/12/23

This Fungus Is Spreading Rapidly in Hospitals
Clip Length 03:24 Premiere Date 04/24/23

There’s Something Living in Wildfire Smoke
Clip Length 01:59 Premiere Date 04/11/23

How the West Is Making It Rain, With Science
Clip Length 06:22 Premiere Date 04/10/23

Soothing Science: The Light You See at Sunset
Clip Length 08:01 Premiere Date 04/04/23

The Mystery and Physics of the Spiral Football Pass
Clip Length 03:43 Premiere Date 02/13/23

Star Chasers of Senegal Preview
Preview Length 00:27 Premiere Date 02/08/23

How to Calculate Time With an Islamic Astrolabe
Clip Length 02:38 Premiere Date 02/08/23

These Ancient Stones Helped Track the Seasons
Clip Length 02:57 Premiere Date 02/08/23

Astronaut Walter Cunningham on the Historic Apollo 7 Mission
Clip Length 32:26 Premiere Date 01/25/23

Six Questions with David Pogue
Clip Length 02:33 Premiere Date 01/04/11

Surviving an Elevator Fall
Clip Length 01:31 Premiere Date 08/23/10

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Why Ships Crash - S49 E9

Nova investigates the 2021 crash of the Ever Given container ship in the Suez Canal and its impact.

  • Tuesday June 6, 2023 12:00 am ET on KET2
  • Monday June 5, 2023 11:00 pm CT on KET2

Operation Lighthouse Rescue - S43 E13

Premiered On: 05/04/2016

Engineers race to rescue the Gay Head Lighthouse, a historic landmark perched high on the cliffs of Martha's Vineyard, soon to become the next victim of the ocean's erosion of the island's cliffs.

  • Wednesday June 7, 2023 9:00 pm ET on KET
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Back to the Moon - S46 E11

Premiered On: 07/10/2019

Fifty years after humans first set foot on the Moon, new scientific discoveries are fueling excitement for a return to the lunar surface. Scientists and engineers are working to make life on the Moon a reality.

  • Wednesday June 14, 2023 9:00 pm ET on KET
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  • Tuesday June 20, 2023 12:00 am ET on KET2
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Why Bridges Collapse - S46 E18

Premiered On: 10/16/2019

"Nova" investigates what may have led to the collapse of the Polcevera Bridge in Genoa, Italy, that killed 43 people. But the Polcevera Bridge isn't alone. Join experts as they compare what happened to the Polcevera with other deadly bridge collapses, including Minnesota's I-35W bridge over the Mississippi and the famed Silver Bridge over the Ohio River.

  • Wednesday June 21, 2023 9:00 pm ET on KET
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  • Monday June 26, 2023 11:00 pm CT on KET2

Ice Age Footprints - S49 E8

Thousands of prehistoric footprints in New Mexico's White Sands National Park capture moments when Ice Age humans crossed paths with enormous ground sloths and mammoths.

  • Wednesday June 28, 2023 9:00 pm ET on KET
  • Wednesday June 28, 2023 8:00 pm CT on KET
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  • Monday July 3, 2023 11:00 pm CT on KET2

Emperor's Ghost Army - S41 E20

Premiered On: 11/12/2014

The program reveals the secrets of China's Terracotta Army, built to serve its first emperor, Qin Shi Huang Di in the afterlife, and brings to life the startlingly sophisticated world of Qin's legendary empire.

  • Wednesday June 28, 2023 10:00 pm ET on KET
  • Wednesday June 28, 2023 9:00 pm CT on KET
  • Friday June 30, 2023 3:00 am ET on KET
  • Friday June 30, 2023 2:00 am CT on KET

The Planets: Inner Worlds - S46 E12

Premiered On: 07/24/2019

The rocky planets - Mercury, Venus, Earth, and Mars - were born of similar material around the same time, yet only one supports life. Were Earth's neighbors always so extreme? Is there somewhere else in the solar system where life might flourish?

  • Wednesday July 5, 2023 10:00 pm ET on KET
  • Wednesday July 5, 2023 9:00 pm CT on KET
  • Thursday July 6, 2023 5:00 pm ET on KET
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Why Ships Crash - S49 E9

  • Monday June 5, 2023 5:00 am ET on KET2
  • Monday June 5, 2023 4:00 am CT on KET2
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Your Brain: Who's in Control? - S50 E10

  • Wednesday May 31, 2023 8:00 am ET on KETWORLD
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Your Brain: Perception Deception - S50 E9

  • Wednesday May 24, 2023 8:00 am ET on KETWORLD
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Hidden Volcano Abyss - S50 E8

  • Wednesday May 17, 2023 8:00 am ET on KETWORLD
  • Wednesday May 17, 2023 7:00 am CT on KETWORLD
  • Wednesday May 17, 2023 12:00 am ET on KETWORLD
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Saving the Right Whale - S50 E7

  • Wednesday May 10, 2023 8:00 am ET on KETWORLD
  • Wednesday May 10, 2023 7:00 am CT on KETWORLD
  • Wednesday May 10, 2023 12:00 am ET on KETWORLD
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