Extras

Video thumbnail: NOVA The Spacetime Lemonade Stand

NOVA

The Spacetime Lemonade Stand

Thirsty for understanding? See how well people on the street can explain spacetime.

The Spacetime Lemonade Stand

Video thumbnail: NOVA Rebuilding 7 World Trade Center

NOVA

Rebuilding 7 World Trade Center

Developer Larry Silverstein explains what's different about the new 7 World Trade Center.

Rebuilding 7 World Trade Center

Video thumbnail: NOVA Solving an Engineering Problem

NOVA

Solving an Engineering Problem

Bracing One World Trade Center's steel frame led to some unexpected perks at the worksite.

Solving an Engineering Problem

Video thumbnail: NOVA The 9/11 Memorial Mock-Up

NOVA

The 9/11 Memorial Mock-Up

Architect and designer Michael Arad takes us on a tour of his 9/11 Memorial mock-up.

The 9/11 Memorial Mock-Up

Video thumbnail: NOVA The Memorial Plaques

NOVA

The Memorial Plaques

Visit the factory where the 9/11 Memorial plaques are made.

The Memorial Plaques

Video thumbnail: NOVA Walls of Glass

NOVA

Walls of Glass

One World Trade Center's glass facade may look fragile, but it is extraordinarily tough.

Walls of Glass

Video thumbnail: NOVA Brian Greene Answers Your Questions

NOVA

Brian Greene Answers Your Questions

Author and physicist Brian Greene answers questions from Facebook and Twitter.

Brian Greene Answers Your Questions

Video thumbnail: NOVA Green Energy in China

NOVA

Green Energy in China

China is ramping up production of solar technology but coal power remains king.

Green Energy in China

Video thumbnail: NOVA A Strict Carbon Diet

NOVA

A Strict Carbon Diet

Saul Griffith has put himself on a strict regime to reduce their carbon footprint.

A Strict Carbon Diet

Video thumbnail: NOVA A Mind for Music

NOVA

A Mind for Music

See neuroscientist Oliver Sacks's brain respond differently to music by Bach & Beethoven.

A Mind for Music

Video thumbnail: NOVA Modeling a Comet Airburst

NOVA

Modeling a Comet Airburst

See why an explosion three miles above Earth would act like a hot tornado on the surface.

Modeling a Comet Airburst

Video thumbnail: NOVA Six Questions with David Pogue

NOVA

Six Questions with David Pogue

The New York Times technology columnist describes the best and strangest gadgets he’s...

Six Questions with David Pogue

Video thumbnail: NOVA Shabbat Elevator

NOVA

Shabbat Elevator

Hotels are offering an innovative way for observant Jews to use elevators on the Sabbath.

Shabbat Elevator

Video thumbnail: NOVA Surviving an Elevator Fall

NOVA

Surviving an Elevator Fall

If an elevator falls, can you save yourself by jumping up at the last second?

Surviving an Elevator Fall

Video thumbnail: NOVA Front Row Seat to Saturn

NOVA

Front Row Seat to Saturn

Out near Saturn, the spacecraft Cassini has just entered its final and riskiest chapter.

Front Row Seat to Saturn