Magipics has produced an astrophysics animation that explains the phenomenon of redshift of distant galaxies. This redshift indicates that most galaxies in the universe are moving away from us (and from each other), and that the universe must be expanding. This cosmological redshift fits in with the Big Bang theory: that our universe began in a tremendous explosion and that space has been expanding ever since.
Redshift means that light or other electromagnetic radiation is shifted towards the red end of the spectrum. In other words, the wavelength of light emitted from an object is increased (and the frequency is lowered) when the object is moving away from the observer.
The redshift of electromagnetic radiation is only one example of the Doppler effect. This effect is defined as an increase (or decrease) in the frequency of sound, light or other waves as the source and the observer move towards (or away from) each other. The audio equivalent of redshift means that the frequency (pitch) of a sound is lowered when the object emitting the sound is moving away from us. This is more obvious the faster the object moves, for example a train or a plane or a passing siren. Conversely, the pitch is increased when the object is moving towards us. In the realm of electromagnetic radiation, this is equivalent to a blue shift.
This animation is part of a series included in ‘CAASTRO in the Classroom‘, an outreach program designed by The Centre of Excellence for All-sky Astrophysics to engage Australian school students and teachers with research scientists. Among other material, the classroom resources include a range of high quality animations to assist in explaining physics concepts and astronomical phenomena for Year 5, 7 and 10 Science and Senior Secondary Physics.
In order to fit in with existing animations in this project and appeal to the target audience, the client requested a more simple/flat 2D or pseudo-3D look.
Parts of this animation have recently (July 2020) been used in the excellent video “So Much Universe, So Little Time. The current crisis in cosmology and how we got here” by ParallaxNick.
Make sure your volume is on, as narration is included!
The animation can also be viewed on the CAASTRO website.
© 2017 Mats Bjorklund