RFI: Calculated orbital decay rate of an unbooster ISS?

On Jun 20, 4:16*am, " wrote:

And, of course, Douglas Adams

If there were going to be lots of them, I'd name some not after Adams
but after some of his ships, starting with Starship Titanic - good
name for something that's only going to be used once, IMHO.

On Thu, 19 Jun 2008 19:55:18 -0500, "Jorge R. Frank"
wrote:

wrote:
On Jun 19, 10:28 am, John Doe wrote:

I assume that the rate of decay would increase as the altitude goes
down. So dropping from 334 to 324 would take less than 3.5 months.

Yes, but as you say, the decay rate goes up as the altitude decreases.
There's a strong dependency on the solar cycle, but in general
altitudes in the 250-300 km range are getting parlously low.

NASA's "line in the sand" for ISS is right within that range, 278 km.

....Quick note of thanks to those who've pointed me in the right
direction towards "back of the envelope" calculations on this. Not
that it's helped Brad Templeton become convinced that we shouldn't be
surprised the Rag Tag Fleet didn't find any satellites or space
stations orbiting the planet they found in the season finale of
"Battlestar Galactica" last week. He's convinced that there won't be
any satellites in GEO more than a few decades from now, much less in
"4000 years".

OM
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In message
OM wrote:

On Thu, 19 Jun 2008 13:16:09 -0700 (PDT), "
wrote:

Supposing a certain europreference and spaceflight orientation, let's
see...

Fritz Lang
Stanislaw Lem
Arthur C. Clarke

And, of course, Douglas Adams

...Gerry Anderson and Terry Nation come to mind as well.

Just as long as "being dead" isn't a requirement.

The Gerry Anderson ought to be a reusable tug anyway, not a cargo pod...

Anthony

Jorge R. Frank wrote:

NASA's "line in the sand" for ISS is right within that range, 278 km.


What happens at that altitude ? Days before it falls out of the sky ?
Hours ? Minutes ?

Or is 278 the point at which the time it would take to launch a
progress/ATV to reboost the ISS would be longer than the time for the
decay to reach re-entry ?

At what altitude do they have to orient the solar arrays so that the
"wind" doesn't blow them off ? Would that be at 278 ? above 278 or below
278km ?

On Jun 19, 10:01*pm, Neil Gerace wrote:

If there were going to be lots of them, I'd name some not after Adams
but after some of his ships, starting with Starship Titanic - good
name for something that's only going to be used once, IMHO.

Ian Banks' Culture ships...

On 25 Jun 2008 15:33:35 -0800, in a place far, far away, Louis
Scheffer made the phosphor on my monitor glow in
such a way as to indicate that:

(Rand Simberg) writes:

No, but more mass reduces the number of reboosts needed.

Once the shuttle no longer visits, has there been any thought of raising the orbit to reduce drag?

Good question. Probably not.

But maybe Jorge knows otherwise.

h (Rand Simberg) writes:

No, but more mass reduces the number of reboosts needed.

Once the shuttle no longer visits, has there been any thought of raising the orbit to reduce drag?

Lou Scheffer

On Jun 25, 6:39 pm, (Rand Simberg)
wrote:
On 25 Jun 2008 15:33:35 -0800, in a place far, far away, Louis
Scheffer made the phosphor on my monitor glow in
such a way as to indicate that:

(Rand Simberg) writes:

No, but more mass reduces the number of reboosts needed.

Once the shuttle no longer visits, has there been any thought of raising the orbit to reduce drag?

Good question. Probably not.

But maybe Jorge knows otherwise.

yes, it will be raise

Louis Scheffer wrote:
h (Rand Simberg) writes:

No, but more mass reduces the number of reboosts needed.

Once the shuttle no longer visits, has there been any thought of raising the orbit to reduce drag?

Already answered earlier in the thread:

"ISS will gradually be boosted back up as the shuttle program ends and
the next solar maximum approaches."

03:18, mercoledì 18 giugno 2008,
Jorge R. Frank:
OM wrote:
...Has anyone done any estimates of roughly how long ISS
could remain in orbit without any boosts from the Shuttle,
Soyuz or Progress resupply missions? The issue has come up
over on a BSG group, and I actually haven't been able to find
anything on the NASA sites about this.

Depends on where the station is within the reboost cycle, but
IIRC it's a minimum of 180 days.


I wonder if they have ever thought using an ion jet engine to
keep ISS in its orbit.

Aren't ion engines more efficient than chemical ones?

Thanks.


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