She's clearly gesturing the idea of 'looking ahead' and 'out there'. She had been doing so for a while, but the screen grab only grabs the one gesture where her hand happens to be flat.

Elon's was clearly a salute, particularly since what he said his action was as he was doing it is the definition of a salute.

I want to thank you for making it happen
*salutes*
My heart goes out to you
~ Musk

salute

1
  a: to address with expressions of kind wishes, courtesy, or honor.

  b: to give a sign of respect, courtesy, or goodwill to [greet]

2
  to become apparent to (one of the senses)

3
  a: to honor (a person, a nation, an event, etc.) by a conventional military or naval ceremony

  b: to show respect and recognition to (a military superior) by assuming a prescribed position  

  c: to express commendation of [praise]

https://www.merriam-webster.com/dictionary/salute