Homepage
Accessibility links
Skip to content
Accessibility Help
BBC Account
Notifications
Home
News
Sport
Weather
iPlayer
Sounds
Bitesize
CBeebies
CBBC
Food
Home
News
Sport
Business
Innovation
Culture
Travel
Earth
Video
Live
More menu
Search BBC
Home
News
Sport
Weather
iPlayer
Sounds
Bitesize
CBeebies
CBBC
Food
Home
News
Sport
Business
Innovation
Culture
Travel
Earth
Video
Live
Close menu
BBC Two
Horizon
Home
Episodes
Clips
Galleries
Information and Support
Main content
2009-2010
Horizon
Series exploring topical scientific issues
On iPlayer
Not available
Supporting Content
Jumping into a black hole
—
Who Is Afraid of a Big Black Hole?
Duration:
4:46
The problem of measuring coastlines
—
How Long is a Piece of String?
Duration:
6:23
Recording data on global population at the UN
—
How Many People Can Live on Planet Earth?
Duration:
4:44
How long is a piece of string?
—
How Long is a Piece of String?
Duration:
6:51
You might also like:
news
|
sport
|
weather
|
worklife
|
travel
|
future
|
culture
|
world
|
business
|
technology
