LEO vs. L1

>
> --- "jdr7181 "
> >
> > Is there a signficant difference in launch costs
> > between launching
> > from the Earth to LEO and launching from the Earth
> > to L1? (I found
>
> Yes.
>
> Delta-V from surface of Earth to LEO at 300 km
> altitude is about 7,800 metres per second.
>
> Delta-V from surface of Earth to LTO (Lunar Transfer
> Orbit - which gets you to L-1 or the Moon) is about
> 10,500 metres per second.
>
> Upon arrival at L-1 (a few days aftger launch) a
> modest braking burn is required which I have
> neglected.
>
> > the answer to this question: One Way - Delta-v =
> > 3.77 km/s (1.87
> > propellant mass surchage); Round Trip - Delta-v =
> > 3.77 km/s (up)
> > + .77 km/s (down) = 4.54 km/s total (2.69 total mass
> > surchage)
>
> I do not understand these numbers.
> They are way too low. Maybe they represent the
> braking burn component, to circularize the elliptical
> LTO orbit at L1.

They came from the source I quoted. Here's the URL to see it yourself
(maybe I misunderstood the context):

http://ares.jsc.nasa.gov/HumanExplore/Exploration/EXLibrary/DOCS/EIC04
2.HTML

Tables 1 and 2.

> What does "round trip" mean in this context ?

From Earth's surface to L1 and back again.

> > Do you know where there are currently any launch
> > vehicles capable of
> > transporting payloads to L1?
> >
> Yes, most launch vehicles can get you to LTO quite
> easily, some need an extra upper stage. Ariane could
> do it quite nicely, also most of the Russian/Ukrainian
> vehicles.
>
> Consider this, the energy to achieve LTO from Earth's
> surface only slightly more than the energy of a
> Geosynchronous transfer orbit.
>
> After separating from the launch vehicle you will
> coast for a few days, then at apogee you will need an
> onboard propulsion system to circularize the orbit.

Can you estimate the difference in cost between launching a satellite
to LEO and launching one to L1? Just pick a size and define the
variable as best you can, if possible.

Jack