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We’re kicking off this month’s ArianeFacts with a basic requirement for sending satellites into orbit 300 km above the Earth’s surface. Why not explain your choice for the non-scientists in our group?
#ArianeGroup #SpaceEnablerspic.twitter.com/YkbrNRuglg
Like a badminton shuttlecock, the faster a flies, the longer it will maintain its altitude. To compensate for the 
’s gravitational pull, it must reach a speed that depends on its altitude. i.e: to remain stationary 300km above the Earth’s surface, it must be moving at 
pic.twitter.com/PwuqMxfdBq
Réponse D
I would have guessed 32000 km/h, so must be D; 28000 km/h :)
D, a satellite has to counter gravity. A, B and C will pull the satellite right back to earth.
28,000 KM/H - Earths gravitational pull is so strong that anything less would pull the satellite back to down. This speed allows it to balance the gravitational pull without leaving orbit all together and heading off into space
Answer D as each orbit takes 90 mins 
Option D. Per its altitude.
Respuesta 28,000 km/h
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