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Falcon Heavy Demonstration Mission [pdf]

spacex.com

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Re: Falcon Heavy Demonstration Mission [pdf]

#11

Post by mstank »

dylan604 wrote: post #7

I saw the video animation of the Tesla separating from the second stage. At that point, the car no longer has thrust, so I'm assuming they've calculated the thrust to be just enough to reach Mars and to be able to fall into orbit. To quote the movie Apollo 13, "we've just put Isaac Newton in the driver's seat". I dearly hope that Musk and team have been referring to the "dummy" in the driver's seat of the Tesla as Is…

From what I understand it won't reach or orbit Mars (not in a current transfer window). It will attempt an approximate Mars-like Hohmann transfer orbit and continue orbiting around the Sun indefinitely.

Re: Falcon Heavy Demonstration Mission [pdf]

#12

Post by garmaine »

dylan604 wrote: post #7

I saw the video animation of the Tesla separating from the second stage. At that point, the car no longer has thrust, so I'm assuming they've calculated the thrust to be just enough to reach Mars and to be able to fall into orbit. To quote the movie Apollo 13, "we've just put Isaac Newton in the driver's seat". I dearly hope that Musk and team have been referring to the "dummy" in the driver's seat of the Tesla as Is…

Reading the OPs link it looks like that animation may have had some dramatic license. They are going to do two more mid coarse corrections on the way to “Mars” if I am reading it right. Of course the red planet won’t actually be there on the other side when they get there.

Also note that you can’t “fall into orbit” around Mars, at least not with this sort of trajectory and without an aero rake heat shield. A real mars mission would require a third stage reignition for Mars orbital insertion.

Re: Falcon Heavy Demonstration Mission [pdf]

#13

Post by garmaine »

api wrote: post #10
dzdt wrote: post #8

Earlier quoted context omitted.

They aren't aiming for Mars orbit. As far as I can tell, they aren't even aiming to come close to Mars. Instead (as far as I can tell) they are aiming to come close to the orbit of Mars, i.e. where Mars will be in 4 or 5 months.

So basically they're just throwing a car into space.

Yes.

Re: Falcon Heavy Demonstration Mission [pdf]

#14

Post by apeace »

dzdt wrote: post #8
dylan604 wrote: post #7

I saw the video animation of the Tesla separating from the second stage. At that point, the car no longer has thrust, so I'm assuming they've calculated the thrust to be just enough to reach Mars and to be able to fall into orbit. To quote the movie Apollo 13, "we've just put Isaac Newton in the driver's seat". I dearly hope that Musk and team have been referring to the "dummy" in the driver's seat of the Tesla as Is…

They aren't aiming for Mars orbit. As far as I can tell, they aren't even aiming to come close to Mars. Instead (as far as I can tell) they are aiming to come close to the orbit of Mars, i.e. where Mars will be in 4 or 5 months.

> Following launch, Falcon Heavy’s second stage will attempt to place the Roadster into a precessing Earth-Mars elliptical orbit around the sun.

Re: Falcon Heavy Demonstration Mission [pdf]

#15

Post by scrumbledober »

Axsuul wrote: post #9

This will be a historic flight. It will be interesting regardless the outcome XD 27 engines! "When Falcon Heavy lifts off in 2018, it will be the most powerful operational rocket in the world by a factor of two"

the most powerful operational rocket, but not the most powerful ever. I believe the Saturn V was more powerful.

Re: Falcon Heavy Demonstration Mission [pdf]

#16

Post by scrumbledober »

owlninja wrote: post #3
garciagomezluis wrote: post #2

http://www.spacex.com/webcast

Did it get delayed? YouTube channel now says going live in another 2 hours

It's currently delayed until about an hour before the launch window closes, and they are hoping for the winds to die down. looks unlikely that they will launch today.

EDIT: nevermind fuel is being loaded and the "holy mouse click" has happened.

Re: Falcon Heavy Demonstration Mission [pdf]

#17

Post by ogre_magi »

apeace wrote: post #14
dzdt wrote: post #8

Earlier quoted context omitted.

They aren't aiming for Mars orbit. As far as I can tell, they aren't even aiming to come close to Mars. Instead (as far as I can tell) they are aiming to come close to the orbit of Mars, i.e. where Mars will be in 4 or 5 months.

> Following launch, Falcon Heavy’s second stage will attempt to place the Roadster into a precessing Earth-Mars elliptical orbit around the sun.

That's not Mars orbit. It's an orbit around the sun with perihelion ~1AU (distance the Earth orbits) and aphelion ~1.5AU (distance Mars orbits [avg]).

Re: Falcon Heavy Demonstration Mission [pdf]

#18

Post by ogre_magi »

api wrote: post #10
dzdt wrote: post #8

Earlier quoted context omitted.

They aren't aiming for Mars orbit. As far as I can tell, they aren't even aiming to come close to Mars. Instead (as far as I can tell) they are aiming to come close to the orbit of Mars, i.e. where Mars will be in 4 or 5 months.

So basically they're just throwing a car into space.

Into deep space. This will be SpaceX's first flight beyond Earth orbit.
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