Diameter1.2 tenths m
2.7 tenthsNecklace lengths
8 thousandthsYacht lengths
120 mm
Photo from Wikimedia Commons
Compact Disc (CD)
The shiny circle that killed the cassette tape/Computing
A standard CD stores 700 MB of data (or about 80 minutes of audio) on a polycarbonate disc 120 mm in diameter and 1.2 mm thick. Data is encoded as microscopic pits 0.5 micrometers wide along a spiral track 5.38 km long, read by a 780 nm infrared laser. CDs were introduced in 1982 and peak production reached 30 billion discs per year in the early 2000s. The format was originally designed to fit Beethoven's Ninth Symphony.
Measurements
Thickness1.2 thousandths m
839 quintillionthsSaturn orbit radii
2,182Green light wavelengths
1.2 mm
Weight1.6 hundredths kg
218 octillionthsMoons
1.9 hundredthsChipotle bowls
9.6 septillionProtons
About 16 grams
Storage capacity700 million B
1.4 millionSlack messages
700Spotify minutes
9,333Emails
700 MB
Data spiral length5,380 m
6.6 hundredthsPanama Canals
67.3City blocks
5.38 km
Pit width500 billionths m
143 billionthsParallel bar lengths
205,761Compton wavelengths
0.5 micrometers