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Light And Distance

Myth vs Reality: Stars, Light, and Time

 This short video addresses the misconception that when we see stars in the night sky, we're seeing them as they are now.
Credits

Light and Distance
 
 
Produced by the Space Telescope Science Institute’s Office of Public Outreach
 
All images, illustrations, and videos courtesy of NASA except:
 
·       Illustration of radiation from everyday objects courtesy of STScI
·       Illustration of electromagnetic waves courtesy of STScI
·       Photo of crepuscular rays courtesy of Wikimedia user Fir0002/Flagstaffotos
·       Photo of snake courtesy of Mark Mannetti
·       Infrared image of a mouse courtesy of Julius Lab, UCSF
·       Photo of snow geese and the Moon courtesy of Brocken Inaglory
·       James Webb Space Telescope illustrations by STScI/G. Bacon
·       Ariane 5 rocket launch image ©2008 ESA – CNES – Arianespace/Photo by Optique Video CSG
·       James Webb Space Telescope animation by STScI/G. Bacon
·       Animation of traveling light pulses courtesy of Footage Island
·       Alpha Centauri animation courtesy of ESO/L. Calçada/Nick Risinger (skysurvey.org)
·       Andromeda Galaxy image courtesy of ESA/Hubble & Digitized Sky Survey 2; acknowledgment: Davide De Martin (ESA/Hubble)
·       Illustration of galaxies at different distances by STScI/A. Field
·       Cosmic redshift animation courtesy of ESO
·       Simulated JWST galaxy field image courtesy of STScI
·       Taurus constellation drawing from Firmamentum Sobiescianum sive Uranographia by Johannes Hevelius, courtesy of the United States Naval Observatory
 
Written by Tracy Vogel
Designed by Marc Lussier 
Music courtesy of Associated Production Music
 
 
Transcript

(SPEECH) 
 [ELECTRONIC MUSIC] 

(DESCRIPTION) 
 Top left, a black and white picture of a minotaur. Top right, a color picture of galaxies. 

Text, MYTH versus REALITY 

Myth side 

Text, When we look at stars in the night sky, we are seeing them in real time. 

Reality side 

Text, All of the stars we can see with the naked eye are in our Milky Way galaxy. But although they are close compared to stars in other galaxies, they are still very far away. It can take several years to thousands of years for light from these stars to reach us. If a star were to explode today, it would be a long time before we saw the event in our sky.