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In article ,
says...

Did SMART-1 get through the belts comparatively quickly compared to
what ISS would, or was it specially hardened, or both?

http://en.wikipedia.org/wiki/SMART-1

From the above:

SMART-1 was launched September 27, 2003 together with Insat 3E
and eBird 1, by an Ariane 5 rocket from the Guiana Space Centre
in French Guiana. After 42 minutes it was released into a
geostationary transfer orbit of 7,035 × 42,223 km. From there
it used its Solar Electric Primary Propulsion (SEPP) to
gradually spiral out during thirteen months.

In other words, it was already above the worst of the inner belt.
Furthermore, due to the highly elliptical orbit, very little time was
spent at lower altitudes.

Here is a cool orbit animation. Crank up the eccentricity to 0.77
(initial orbit eccentricity of SMART-1) and you'll see how little time
is spent at the lower altitudes in an orbit this eccentric.

van-Allen belts (the inner belt is "the worst" of the two in terms of
radiation):

http://en.wikipedia.org/wiki/Van_Allen_radiation_belt

Jeff
--
" Ares 1 is a prime example of the fact that NASA just can't get it
up anymore... and when they can, it doesn't stay up long. "
- tinker

In sci.space.history Jeff Findley wrote:
In article ,
Did SMART-1 get through the belts comparatively quickly compared to
what ISS would, or was it specially hardened, or both?

In other words, it was already above the worst of the inner belt.
Furthermore, due to the highly elliptical orbit, very little time was
spent at lower altitudes.

So, it got through quickly

Here is a cool orbit animation. Crank up the eccentricity to 0.77
(initial orbit eccentricity of SMART-1) and you'll see how little time
is spent at the lower altitudes in an orbit this eccentric.

van-Allen belts (the inner belt is "the worst" of the two in terms of
radiation):

http://en.wikipedia.org/wiki/Van_Allen_radiation_belt

I might be dense and missed where in the wikipedia article the
simululation was, or is there a missing link?

rick
--
denial, anger, bargaining, depression, acceptance, rebirth...
where do you want to be today?
these opinions are mine, all mine; HP might not want them anyway...
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

In article ,
says...

In sci.space.history Jeff Findley wrote:
In article ,
Did SMART-1 get through the belts comparatively quickly compared to
what ISS would, or was it specially hardened, or both?

In other words, it was already above the worst of the inner belt.
Furthermore, due to the highly elliptical orbit, very little time was
spent at lower altitudes.

So, it got through quickly

Not happening with Bob's proposal to boost ISS using VASIMR.

Here is a cool orbit animation. Crank up the eccentricity to 0.77
(initial orbit eccentricity of SMART-1) and you'll see how little time
is spent at the lower altitudes in an orbit this eccentric.

van-Allen belts (the inner belt is "the worst" of the two in terms of
radiation):

http://en.wikipedia.org/wiki/Van_Allen_radiation_belt

I might be dense and missed where in the wikipedia article the
simululation was, or is there a missing link?

I must have forgotten to paste that link:

http://www.windows2universe.org/phys...echanics/orbit
/orbit_shape_interactive.html

From the above, you'll be able to visualize how a highly eccentric orbit
helps avoid the radiation of the lower van-Allen belt (by spending very
little time at lower altitudes).

Jeff
--
" Ares 1 is a prime example of the fact that NASA just can't get it
up anymore... and when they can, it doesn't stay up long. "
- tinker

nasa may have been concerned a space tug could hurt contractors somhow
and saved money. plus a new model space tug would likely be more
efficent.

there are lots of reasons one was never built

In article 7751f3da-1cc9-48fc-8b10-
, says...

nasa may have been concerned a space tug could hurt contractors somhow
and saved money. plus a new model space tug would likely be more
efficent.

there are lots of reasons one was never built

There was never any conspiracy. There was just no money for on OTV.
The shuttle program (followed by Freedom/ISS) gobbled up nearly the
entire NASA manned space budget.

Jeff
--
" Ares 1 is a prime example of the fact that NASA just can't get it
up anymore... and when they can, it doesn't stay up long. "
- tinker

On Oct 5, 8:38*am, Jeff Findley wrote:
In article 7751f3da-1cc9-48fc-8b10-
, says...



nasa may have been concerned a space tug could hurt contractors somhow
and saved money. plus a new model space tug would likely be more
efficent.

there are lots of reasons one was never built

There was never any conspiracy. *There was just no money for on OTV. *
The shuttle program (followed by Freedom/ISS) gobbled up nearly the
entire NASA manned space budget.

Jeff
--
" Ares 1 is a prime example of the fact that NASA just can't get it
* up anymore... and when they can, it doesn't stay up long. "
* *- tinker

the tug proposal goes back to skylab, it was suggested to boost
skylabs orbit, to use it some way for future operations

In article 0ca89545-f94b-4e02-82b2-73e5cc013b01@
18g2000yqz.googlegroups.com, says...

On Oct 5, 8:38*am, Jeff Findley wrote:
In article 7751f3da-1cc9-48fc-8b10-
, says...
nasa may have been concerned a space tug could hurt contractors
somhow
and saved money. plus a new model space tug would likely be more
efficent.

there are lots of reasons one was never built

There was never any conspiracy. *There was just no money for on OTV. *
The shuttle program (followed by Freedom/ISS) gobbled up nearly the
entire NASA manned space budget.

Jeff
--
" Ares 1 is a prime example of the fact that NASA just can't get it
* up anymore... and when they can, it doesn't stay up long. "
* *- tinker

the tug proposal goes back to skylab, it was suggested to boost
skylabs orbit, to use it some way for future operations

You're confusing different proposals for different vehicles. The Skylab
Reboost Module was a cobbled together conglomeration of hardware meant
for one use only. It was not a general purpose "space tug".

http://www.astronautix.com/flights/sts2a.htm
http://www.astronautix.com/craft/skyodule.htm

Various "space tug" concepts which were designed for general use have
come and gone over the years.

OTV (orbital transfer vehicle).
http://www.astronautix.com/craft/otv.htm

Orbital Maneuvering Vehicle
http://www.astronautix.com/craft/omv.htm

I've seen similar proposals from around the same time period which
aren't documented on the Internet. Somewhere at home, I've got some
magazine articles I saved which show a manned OTV which predated the
version above. The version I remember did not use aerobraking.



A modern version of a space tug "on the cheap" could be a modified Orion
service module or ESA's ATV without the pressurized section. Both of
these would be similar to the modified Progress propulsion module which
the Russians have used to deliver docking/airlock modules to ISS. The
problem is, where is the need for such a vehicle? Just what would NASA
use it for?


MDA is working on a commercial satellite servicing vehicle which might
also be useful as a small "tug". If there is a commercial need for such
a vehicle, I'd expect companies like MDA to provide such a service.

http://www.mdacorporation.com/corpor...iceMission.cfm


It's also possible that other commercial companies could provide similar
services, if needed. Pretty much any company doing commercial ISS
resupply would have the skills needed to build and operate such a
vehicle.

Jeff
--
" Ares 1 is a prime example of the fact that NASA just can't get it
up anymore... and when they can, it doesn't stay up long. "
- tinker