The Doppler effect is the change in frequency or wavelength of a wave for an observer who is moving relative to the wave source. It is named after the Austrian physicist Christian Doppler, who described the phenomenon in 1842. A common example of Doppler shift is the change of pitch heard when a vehicle sounding a horn approaches and recedes from an observer. Compared to the emitted frequency, the received frequency is higher during the approach, identical at the instant of passing by, and lower during the recession. Credit: ROYAL OBSERVATORY GREENWITCH Follow Us: Facebook: https://goo.gl/QapZAe Twitter: https://goo.gl/RoQSmJ #DeepSpaceTV #DoplerEffects #AlienWorlds ... https://www.youtube.com/watch?v=xqNkF5Kqm1U

Dig deep into the workings of Earth’s next trip to the Red Planet. InSight, scheduled to launch in May, 2018, will be the first NASA mission to observe the deep interior of Mars and learn about the history and evolution of rocky planets. See the instruments InSight will bring to Mars, including the first seismometer ever taken to the surface of another planet. Credit: NASA JPL Follow Us: Facebook: https://goo.gl/QapZAe Twitter: https://goo.gl/RoQSmJ #DeepSpaceTV #MarsInsight #PlanetMars ... https://www.youtube.com/watch?v=1EYDaPrWPlg

Space Shuttle Endeavour is a retired orbiter from NASA's Space Shuttle program and the fifth and final operational shuttle built. Credit: NASA Follow Us: Facebook: https://goo.gl/QapZAe Twitter: https://goo.gl/RoQSmJ #DeepSpaceTV #SpaceShuttleEndeavour #SpaceShuttleProgram ... https://www.youtube.com/watch?v=_ZZC5ofEDQM

Credit: NASA Follow Us: Facebook: https://goo.gl/QapZAe Twitter: https://goo.gl/RoQSmJ #DeepSpaceTV #Apollo11 #LiveSpaceBroadcast ... https://www.youtube.com/watch?v=7YFBPV12JZQ