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Main
Date: 29 Jul 2007 04:25:03
From: Bjørn Sørheim
Subject: ISS sightings and its orbit
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Concerning a question of:
Was that observation of a moving light in the sky ISS or not?
If ISS have been seen at a certain point in time.
Then the previous orbit (about 90 minutes earlier), how much in
degrees (as projected on the globe) is this orbit different from the next,
and in which direction.
Put in another way: How much does the nothernmost point of the orbit of
ISS move between each pass and in which direction, east or west?
(BTW, I want to leave out the factor of earth shadow here, as this is a case
of summer sighting at high lattitudes.)
Bjørn
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Date: 31 Jul 2007 21:59:39
From: Dr J R Stockton
Subject: Re: ISS sightings and its orbit
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In sci.space.station message <46af5e3d.7955337@news.uunet.co.za >, Tue,
31 Jul 2007 16:08:56, Eugene Griessel <eugene@dynagen.?.co.?.za.invalid >
posted:
>John Szalay <john.szalay@pullmyfinger.att.net> wrote:
>
>>BTW: Not knowing what part of Norway you are in, I used Oslo as a
>>viewing site and ran some predictions, and find that the highest you can
>>expect ISS to be above the horz, is about 16 deg. but then I did't run
>>a lot of passes. nor did I check the overlap on passes.
>
>Yes - about right. I figure about 15 degrees 39 minutes, but am
>taking Oslo at sea level - so perhaps a bit higher if on higher
>ground. The furthest North it can be seen, from my calculations,
>appears to be just over 70 degrees.
My javascript calculator gives, for a current altitude of 342 km and
0.4 degrees above horizon, a distance of 2000 km, which, by the original
definition of the metre, is 18 degrees of latitude. ISS can pass
slightly North of here, reaching about 52 degrees N; so your 70 deg N is
confirmed,
--
(c) John Stockton, Surrey, UK. ?@merlyn.demon.co.uk Turnpike v6.05 MIME.
Web <URL:http://www.merlyn.demon.co.uk/ > - FAQqish topics, acronyms & links;
Astro stuff via astron-1.htm, gravity0.htm ; quotings.htm, pascal.htm, etc.
No Encoding. Quotes before replies. Snip well. Write clearly. Don't Mail News.
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Date: 30 Jul 2007 14:23:38
From: John Szalay
Subject: Re: ISS sightings and its orbit
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"Bjørn Sørheim" <bsoerhei@nixspam.online.no > wrote in
news:46abfa81$1@news.broadpark.no:
> Concerning a question of:
> Was that observation of a moving light in the sky ISS or not?
>
> If ISS have been seen at a certain point in time.
>
> Then the previous orbit (about 90 minutes earlier), how much in
> degrees (as projected on the globe) is this orbit different from the
> next, and in which direction.
>
> Put in another way: How much does the nothernmost point of the orbit
> of ISS move between each pass and in which direction, east or west?
>
> (BTW, I want to leave out the factor of earth shadow here, as this is
> a case of summer sighting at high lattitudes.)
>
> Bjørn
>
>
>
The tracking program I have used for years is called STSPLUS
written by the Late Dave Ransom, once you get it running and keep
current TLE's plugged in, its great for predicting ISS passes weeks in
advance. for most anyplace on earth.
I've used it with DOS WIN3.1 Win95 Win98 and now XP.
have not been able to get it to run under Vista yet..
You as the user get to set the specs as to visiblity (sightings)
or for radio so you know when its within range to hear (If they using
the Ham radio setup) even if you can not see it.
its still available from several Ham radio and university websites
used to be available from the NASA Spacelink site, not sure if
its still there.
Sorry to lose Dave , he was a very knowledgable gentleman..
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Date: 31 Jul 2007 01:08:37
From: Bjørn Sørheim
Subject: Re: ISS sightings and its orbit
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"John Szalay" <john.szalay@pullmyfinger.att.net > skrev i melding
news:Xns997D9CA57BB6Cjohnszalayattnet@216.196.97.142...
> "Bjørn Sørheim" <bsoerhei@nixspam.online.no> wrote in
> news:46abfa81$1@news.broadpark.no:
>>
> The tracking program I have used for years is called STSPLUS
> written by the Late Dave Ransom, once you get it running and keep
> current TLE's plugged in, its great for predicting ISS passes weeks in
> advance. for most anyplace on earth.
Can you also use it for passes that already have ocurred??
A week or weeks before?
-Bjørn
> I've used it with DOS WIN3.1 Win95 Win98 and now XP.
> have not been able to get it to run under Vista yet..
>
> You as the user get to set the specs as to visiblity (sightings)
> or for radio so you know when its within range to hear (If they using
> the Ham radio setup) even if you can not see it.
>
> its still available from several Ham radio and university websites
> used to be available from the NASA Spacelink site, not sure if
> its still there.
>
> Sorry to lose Dave , he was a very knowledgable gentleman..
>
>
>
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Date: 31 Jul 2007 10:07:15
From: John Szalay
Subject: Re: ISS sightings and its orbit
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"Bjørn Sørheim" <bsoerhei@nixspam.online.no > wrote in news:46ae6f7b$1@
>
> Can you also use it for passes that already have ocurred??
> A week or weeks before?
>
> -Bjørn
>
>
Yes, but it involves reseting your computers clock to the earlier
day/time period
AND using TLEs from that same time period. so you need to have them on
archive
but it works , gets a little tricky but it works.. then you have to
reset everything to keep up to date. It got a little harder to do that
with Windows XP, because XP seems to want to verify file time stamps..
when I want to do things like checking old passes OR take a computer
outside to watch the ISS or shuttle passes, I use an older laptop
running DOS, runs faster, boots faster and easier to fool the CPU into
excepting the false time settings..
BTW: Not knowing what part of Norway you are in, I used Oslo as a
viewing site and ran some predictions, and find that the highest you can
expect ISS to be above the horz, is about 16 deg. but then I did't run
a lot of passes. nor did I check the overlap on passes.
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Date: 31 Jul 2007 16:08:56
From: Eugene Griessel
Subject: Re: ISS sightings and its orbit
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John Szalay <john.szalay@pullmyfinger.att.net > wrote:
>BTW: Not knowing what part of Norway you are in, I used Oslo as a
>viewing site and ran some predictions, and find that the highest you can
>expect ISS to be above the horz, is about 16 deg. but then I did't run
>a lot of passes. nor did I check the overlap on passes.
Yes - about right. I figure about 15 degrees 39 minutes, but am
taking Oslo at sea level - so perhaps a bit higher if on higher
ground. The furthest North it can be seen, from my calculations,
appears to be just over 70 degrees.
Eugene L Griessel
You gotta have a swine to show you where the truffles are.
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Date: 31 Jul 2007 14:32:32
From: John Szalay
Subject: Re: ISS sightings and its orbit
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eugene@dynagen..co..za (Eugene Griessel) wrote in news:46af5e3d.7955337
@news.uunet.co.za:
> John Szalay <john.szalay@pullmyfinger.att.net> wrote:
>
>>BTW: Not knowing what part of Norway you are in, I used Oslo as a
>>viewing site and ran some predictions, and find that the highest you
can
>>expect ISS to be above the horz, is about 16 deg. but then I did't
run
>>a lot of passes. nor did I check the overlap on passes.
>
> Yes - about right. I figure about 15 degrees 39 minutes, but am
> taking Oslo at sea level - so perhaps a bit higher if on higher
> ground. The furthest North it can be seen, from my calculations,
> appears to be just over 70 degrees.
>
>
> Eugene L Griessel
>
> You gotta have a swine to show you where the truffles are.
>
Did a quick run using Oslo as the site and UTC
so I MAY have, and MOST LIKELY have overlooked something. BUT..
Looks like the next possible visible pass is 12th of Aug at 7:34PM UTC
17 deg above the horiz.
Latitude: 59.9333 N
Longitude: 10.6833 E
Elevation: 15 meters
Prepared: 31 JUL 2007 15:09:43 MST
Satellite Name: ISS Space Station
Catalog Number: 25544 98067A
Pass Type: Visible, MinAlt = 5 deg, MinHor = 3 deg
TLE Filename: VISUAL.TXT
-----------AOS----------- --MAX VISIBILITY-- ------LOS------
# MST Date & Time Azm MST Time Alt Azm MST Time Azm
Duration
26 12 AUG 07 19:29:41 246.7 19:34:04 17 183.2 19:38:27 119.3
VIS: 19:30:29 241.9 19:34:04 17 183.2 19:37:41 123.9
27 12 AUG 07 21:04:22 257.2 21:08:21 11 202.6 21:12:19 147.8
VIS: 21:05:16 250.1 21:08:21 11 202.6 21:09:06 187.7
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Date: 01 Aug 2007 07:32:54
From: Eugene Griessel
Subject: Re: ISS sightings and its orbit
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John Szalay <john.szalay@pullmyfinger.att.net > wrote:
>eugene@dynagen..co..za (Eugene Griessel) wrote in news:46af5e3d.7955337
>@news.uunet.co.za:
>
>> John Szalay <john.szalay@pullmyfinger.att.net> wrote:
>>
>>>BTW: Not knowing what part of Norway you are in, I used Oslo as a
>>>viewing site and ran some predictions, and find that the highest you
>can
>>>expect ISS to be above the horz, is about 16 deg. but then I did't
>run
>>>a lot of passes. nor did I check the overlap on passes.
>>
>> Yes - about right. I figure about 15 degrees 39 minutes, but am
>> taking Oslo at sea level - so perhaps a bit higher if on higher
>> ground. The furthest North it can be seen, from my calculations,
>> appears to be just over 70 degrees.
>>
>>
>> Eugene L Griessel
>>
>> You gotta have a swine to show you where the truffles are.
>>
>
>Did a quick run using Oslo as the site and UTC
>so I MAY have, and MOST LIKELY have overlooked something. BUT..
>
>Looks like the next possible visible pass is 12th of Aug at 7:34PM UTC
> 17 deg above the horiz.
>
>Latitude: 59.9333 N
> Longitude: 10.6833 E
> Elevation: 15 meters
>Prepared: 31 JUL 2007 15:09:43 MST
>
>Satellite Name: ISS Space Station
>Catalog Number: 25544 98067A
>Pass Type: Visible, MinAlt = 5 deg, MinHor = 3 deg
>TLE Filename: VISUAL.TXT
>
> -----------AOS----------- --MAX VISIBILITY-- ------LOS------
> # MST Date & Time Azm MST Time Alt Azm MST Time Azm
>Duration
>
>26 12 AUG 07 19:29:41 246.7 19:34:04 17 183.2 19:38:27 119.3
> VIS: 19:30:29 241.9 19:34:04 17 183.2 19:37:41 123.9
>27 12 AUG 07 21:04:22 257.2 21:08:21 11 202.6 21:12:19 147.8
> VIS: 21:05:16 250.1 21:08:21 11 202.6 21:09:06 187.7
Using your location criteria I get a fair pass for the 5th with a 16.1
degree elevation at 21:40:19 UTC. Another on the 6th at 20:28:23 with
an elevation of 13.3 degrees and another on the same day at 22:02:11
at 15.7 degree elevation. Your pass of the 12th seems to me will be
in eclipse before it reaches maximum elevation.
Eugene L Griessel
Equality may perhaps be a right, but no power on earth can ever
turn it into a fact.
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Date: 01 Aug 2007 09:31:49
From: John Szalay
Subject: Re: ISS sightings and its orbit
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eugene@dynagen..co..za (Eugene Griessel) wrote in news:46b035e4.3902586
> Using your location criteria I get a fair pass for the 5th with a 16.1
> degree elevation at 21:40:19 UTC. Another on the 6th at 20:28:23 with
> an elevation of 13.3 degrees and another on the same day at 22:02:11
> at 15.7 degree elevation. Your pass of the 12th seems to me will be
> in eclipse before it reaches maximum elevation.
>
> Eugene L Griessel
>
ran it again, and it appears you are right on the 5th and 6th, but I still
show it good on the 12th. its right after sunset, so the might be rather
bright.
I'll check my times and stats and run it again..
Would be nice to know right where he is in Norway..
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Date: 30 Jul 2007 17:02:28
From: Dr J R Stockton
Subject: Re: ISS sightings and its orbit
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In sci.astro.amateur message <46ac91c7$1@news.broadpark.no >, Sun, 29 Jul
2007 15:10:15, Bjørn Sørheim <bsoerhei@nixspam.online.no > posted:
>I have always used heavensabove for these kinds of questions.
>But it actually have serious limitations.
>It has a cutoff of about 10 degrees in horisont height.
>It will not show a pass if it is dusk or dawn.
>ISS has now a magnitude of -4.7 in the best of locations.
>Certainly seen at dusk or dawn.
The main.asp page of Heavens-Above will show the current location of
ISS, so that if you can look at H-A at the time of a future possible ISS
sighting you can tell whether ISS might be visible.
The height of ISS is currently about 340 km, so if you see ISS at a
height of one degree, it must be about 2000 km away. Enter a location
about 2000 km to your South, and passes that you would see very low
would certainly be reported by H-A in Summer, where sunset there will be
earlier too. If you are near Oslo, try Sardinia.
Google for ISS elements finds <http://www.eharm.net/shop/freeware/or
biter/orbiter_faq/tips/iss_elements.html >, <http://spaceflight.nasa.gov/
realdata/sightings/SSapplications/Post/JavaSSOP/orbit/ISS/SVPOST.html >
and adding orbit finds <http://spaceflight.nasa.gov/realdata/element
s/ >. And <http://spaceflight.nasa.gov/realdata/tracking/index.html>
apparently also shows where it is.
Try also via <http://www.esa.int/esaCP/ESAWW4KE43D_FeatureWeek_0.html >.
--
(c) John Stockton, Surrey, UK. ?@merlyn.demon.co.uk Turnpike v6.05 MIME.
Web <URL:http://www.merlyn.demon.co.uk/ > - FAQqish topics, acronyms & links;
Astro stuff via astron-1.htm, gravity0.htm ; quotings.htm, pascal.htm, etc.
No Encoding. Quotes before replies. Snip well. Write clearly. Don't Mail News.
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Date: 30 Jul 2007 06:32:07
From: Kevin
Subject: Re: ISS sightings and its orbit
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Starry Night software can identify the ISS. Once I saw a bright object, and
checked on Starry Night for that time and location, and it was in fact ISS.
"Bjørn Sørheim" <bsoerhei@nixspam.online.no > wrote in message
news:46abfa81$1@news.broadpark.no...
> Concerning a question of:
> Was that observation of a moving light in the sky ISS or not?
>
> If ISS have been seen at a certain point in time.
>
> Then the previous orbit (about 90 minutes earlier), how much in
> degrees (as projected on the globe) is this orbit different from the
> next,
> and in which direction.
>
> Put in another way: How much does the nothernmost point of the orbit of
> ISS move between each pass and in which direction, east or west?
>
> (BTW, I want to leave out the factor of earth shadow here, as this is a
> case
> of summer sighting at high lattitudes.)
>
> Bjørn
>
>
>
>
>
-----------------
www.Newsgroup-Binaries.com - *Completion*Retention*Speed*
Access your favorite newsgroups from home or on the road
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Date: 29 Jul 2007 03:00:48
From: JF Mezei
Subject: Re: ISS sightings and its orbit
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Bjørn Sørheim wrote:
> Concerning a question of:
> Was that observation of a moving light in the sky ISS or not?
Can't tell just from that. There are a number of satellites that appear
as a moving light in the sky. And depending on orbit, position of sunn,
etc, sometimes they may appear brighter than the ISS if the ISS passes
over you in a way that it isn't brightly lighted.
There are NASA sites (and others) which tell you when there is a visible
ISS pass over you, and what arc it should produce in the sky.
The ISS' northermost point is roughly 52° latitude. Your own location is
very importantly in how the ISS can be seen.
> Then the previous orbit (about 90 minutes earlier), how much in
> degrees (as projected on the globe) is this orbit different from the next,
> and in which direction.
The earth rotates once per 24 hours. This means that at equator, a pass
moves west by about 2500km each 90 minutes. (40000km circumference in 24
hours = 1666km/h).
At equator, you get both ascending (travelling north-east) and
descending (travelling south-east) node passes. north-east, At northern
latitudes, you only basically see a west to east travel, one opportunity
per orbit since this when when the asecending node becomes a descending
node.
http://science.nasa.gov/RealTime/
The above gives you some ISS tracking and sighting predictions. JPASS
can describe to you where on the sky each ISS pass will be visible from
your latitude/longitude.
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Date: 29 Jul 2007 15:10:15
From: Bjørn Sørheim
Subject: Re: ISS sightings and its orbit
|
I have always used heavensabove for these kinds of questions.
But it actually have serious limitations.
It has a cutoff of about 10 degrees in horisont height.
It will not show a pass if it is dusk or dawn.
ISS has now a magnitude of -4.7 in the best of locations.
Certainly seen at dusk or dawn.
I have a possible sighting of ISS with magnitude of about -3.
It doesn't show up on heavensabove -but maybe not so strange giving the
limitations
mentioned.
One of the sites you mention:
http://spaceflight1.nasa.gov/realdata/sightings/ (Skywatch)
is supposed to also go back in time, as I need, but it dosn't work!
(I need to go back one week.)
So, is there a site on the web which are without the limitations mentioned,
showing all
passes in the whole sky from a location without caring about light
conditions?
ISS has become, with its growing size and brightness, a very special
satellite
that can be seen under quite different conditions than all the other
satellites -
without of course taking into account special cases like 'Iridium' etc.
-Bjørn
"JF Mezei" <jfmezei.spamnot@vaxination.ca > skrev i melding
news:3c938$46ac3b7f$cef8887a$9150@TEKSAVVY.COM...
> Bjørn Sørheim wrote:
>> Concerning a question of:
>> Was that observation of a moving light in the sky ISS or not?
>
> Can't tell just from that. There are a number of satellites that appear as
> a moving light in the sky. And depending on orbit, position of sunn, etc,
> sometimes they may appear brighter than the ISS if the ISS passes over you
> in a way that it isn't brightly lighted.
>
> There are NASA sites (and others) which tell you when there is a visible
> ISS pass over you, and what arc it should produce in the sky.
>
> The ISS' northermost point is roughly 52° latitude. Your own location is
> very importantly in how the ISS can be seen.
>
>
>> Then the previous orbit (about 90 minutes earlier), how much in
>> degrees (as projected on the globe) is this orbit different from the
>> next,
>> and in which direction.
>
> The earth rotates once per 24 hours. This means that at equator, a pass
> moves west by about 2500km each 90 minutes. (40000km circumference in 24
> hours = 1666km/h).
>
> At equator, you get both ascending (travelling north-east) and descending
> (travelling south-east) node passes. north-east, At northern latitudes,
> you only basically see a west to east travel, one opportunity per orbit
> since this when when the asecending node becomes a descending node.
>
> http://science.nasa.gov/RealTime/
>
> The above gives you some ISS tracking and sighting predictions. JPASS can
> describe to you where on the sky each ISS pass will be visible from your
> latitude/longitude.
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