earlier question

No one answered before so I'll try again :-) Call me persistent!

Why are the landing times getting later w/each day - the launch times
got earlier each day - is that always the case or did they do something
different this time around?

Secondly, if they prefer day landings to night ones, and the weather
forecast looks to be ideal for each opportunity tomorrow, would they
consider only focusing on the second chance? On STS-85 they did that;
only targeted the daylight chance and were going to focus on both
chances if they'd been waived off a day for the 2nd time, at which
point they'd also have called up Edwards..

Danny Dot wrote:
wrote in message
oups.com...
No one answered before so I'll try again :-) Call me persistent!

Why are the landing times getting later w/each day - the launch times
got earlier each day - is that always the case or did they do something
different this time around?

Secondly, if they prefer day landings to night ones, and the weather
forecast looks to be ideal for each opportunity tomorrow, would they
consider only focusing on the second chance? On STS-85 they did that;
only targeted the daylight chance and were going to focus on both
chances if they'd been waived off a day for the 2nd time, at which
point they'd also have called up Edwards..


I worked for NASA for 15 years and never did figure out launch and landing
windows. I have been in many meetings that had charts with about 100 lines
on them discussing the subject. I think NASA hires autistic savants to
understand this stuff, e.g. the movie Rain Man. It is in my opinion
impossible for a normal person to understand the subject :-) I think it
would be easier to solve the Unified Field Theorem than to figure out launch
and landing windows :-)

Danny Dot
www.mobbinggonemad.org

wrote in message
oups.com...
No one answered before so I'll try again :-) Call me persistent!

Why are the landing times getting later w/each day - the launch times
got earlier each day - is that always the case or did they do something
different this time around?

I believe that's pretty much always the case.

Basically as ISS orbits the earth, its orbit precesses around the planet so
that the plane of the orbit changes over time.

So, from the POV of the Earth, the shuttle has to launch about an hour
earlier in order to intercept the orbital plane.


For descent, you have something similar, but now you can land on the
"ascending" or "descending" node. (i.e. does it approach from the north or
south essentially. But there are constraints on that so as to avoid
populated areas, etc.)



Secondly, if they prefer day landings to night ones, and the weather
forecast looks to be ideal for each opportunity tomorrow, would they
consider only focusing on the second chance? On STS-85 they did that;
only targeted the daylight chance and were going to focus on both
chances if they'd been waived off a day for the 2nd time, at which
point they'd also have called up Edwards..

That's what I thought too (ascending v. descending). But I thought
that meant drastically changing their sleep patterns and also that
they'd come in from the north - I remember one coming back from Mir
(STS-74 I think) and seeing spectacular footage later of them coming
across southern Alaska and the Canadian Rockies and across the midwest
and south into KSC.. but this one's coming from the south like 'normal'
Oh well..





Greg D. Moore (Strider) wrote:
wrote in message
oups.com...
No one answered before so I'll try again :-) Call me persistent!

Why are the landing times getting later w/each day - the launch times
got earlier each day - is that always the case or did they do something
different this time around?

I believe that's pretty much always the case.

Basically as ISS orbits the earth, its orbit precesses around the planet so
that the plane of the orbit changes over time.

So, from the POV of the Earth, the shuttle has to launch about an hour
earlier in order to intercept the orbital plane.


For descent, you have something similar, but now you can land on the
"ascending" or "descending" node. (i.e. does it approach from the north or
south essentially. But there are constraints on that so as to avoid
populated areas, etc.)



Secondly, if they prefer day landings to night ones, and the weather
forecast looks to be ideal for each opportunity tomorrow, would they
consider only focusing on the second chance? On STS-85 they did that;
only targeted the daylight chance and were going to focus on both
chances if they'd been waived off a day for the 2nd time, at which
point they'd also have called up Edwards..

"Danny Dot" wrote in message
...

I worked for NASA for 15 years and never did figure out launch and landing
windows. I have been in many meetings that had charts with about 100
lines on them discussing the subject. I think NASA hires autistic savants
to understand this stuff, e.g. the movie Rain Man. It is in my opinion
impossible for a normal person to understand the subject :-) I think it
would be easier to solve the Unified Field Theorem than to figure out
launch and landing windows :-)

I take it you never studied orbital mechanics?

Jeff
--
"They that can give up essential liberty to obtain a
little temporary safety deserve neither liberty nor
safety"
- B. Franklin, Bartlett's Familiar Quotations (1919)