- #36
DaveC426913
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In this article http://www.einsteins-theory-of-relativity-4engineers.com/twin-paradox-2.html
This graph shows what a receding observer sees. Look at the left graph, bottom half. Eartyh stays put (Y-axis/time axis), spaceship moves away to right.
A signal sent out from Earth every year is received on the spaceship every two years. i.e. the spaceship on its 4 year outward journey (2007 to 2011) only receives only 2 yearly greetings from Earth.
(Of course, after it turns around, it receives 7 greetings on its 4 year homeward journey.)
This graph shows what a receding observer sees. Look at the left graph, bottom half. Eartyh stays put (Y-axis/time axis), spaceship moves away to right.
A signal sent out from Earth every year is received on the spaceship every two years. i.e. the spaceship on its 4 year outward journey (2007 to 2011) only receives only 2 yearly greetings from Earth.
(Of course, after it turns around, it receives 7 greetings on its 4 year homeward journey.)