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Space Shuttle Rendezvous with Space Station

Below are some excerpts, mainly from the SeeSat-L mailing list, which appeared on the Internet during the recent mission of Discovery, STS-63.

Date: Fri, 3 Feb 95 06:36:00 UTC

From: jay.respler@genie.geis.com

12:29:16 am EST. SAW DISCOVERY RISING IN THE SOUTH!!

Easily followed it with naked eye for a minute from here in New Jersey. Then it faded from sight. Using binoculars, every few seconds it would pulse into view till it set behind trees in the ESE at 12:31:00.

It's great having these launches at night so I can see them.

Date: Fri Feb 3 22:56:53 1995

From: jeff@ursa-major.spdcc.com (Jeff Fabijanic)

Just watched the Shuttle launch on the NASA channel. About 60 seconds after launch, Kris and I went up on the roof to see if we could do an unassisted sighting. We went up a little too early and saw nothing. When I came down the shuttle was just reaching about 400 nautical miles elevation and I decided to try again before the boosters were spent.

Went up on the roof and instantly picked out the shuttle! About 6 degrees above the horizon, SSE. It's apparent brightness varied from 5 to 0. For the most part, around magnitude 1. In less than 30 seconds, it had passed to the NE where we lost it, probably a combination of weather and MECO. Easily viewed with the naked eye.

That makes two very dramatic naked eye sightings in just a couple months (we watched the fly over of STS 61 last year), Did anyone else get a look at STS 63 tonite?

Date: Sat Feb 4 08:57:25 1995

From: sventekp@cuug.ab.ca (Paul Sventek)

Bill Bard's msg giving STS-63 element set JSC-004 is still quite correct for now at predicting STS-63 visibility. MIR passed over Calgary, Alberta (51N 114W) at 13:21 UT Saturday morning with the Shuttle following 20 minutes later.

From: brand@csgrad.cs.vt.edu (Jeff Brandenburg)

Date: Sat Feb 4 16:56:12 1995

I spotted it from Lancaster, PA. I would have estimated it at maybe -1 or -2; seemed brighter than Sirius. I'm not sure how long I tracked it as it moved from SSE toward NE, but I believe it was longer than a minute. It appeared distinctly orange, and pulsed with a period > 1 sec. I didn't start looking for it until after booster separation, and it was a couple of minutes before it appeared.

From: ai@iol.ie (Astronomy Ireland)

Date: Sun Feb 5 03:19:55 1995

Saw space shuttle Discovery (STS-63) from Dublin, Ireland (53.2742N, 6.3588W, 95m above sea level) at Sunday 1995 Feb. 5d 06h 28m 47.30s U.T. when it passed Spica (V=0.97) which was about 22 deg. above SW horizon. Discovery was as bright as Spica = mag +1, about 850km from me.

I had a look in binoculars in case anything visible near it. I saw it was hazy but thought this was due to thin clouds that had (miraculously) cleared only minutes earlier. Then I noticed 'haze' was on one side only and checked nearby stars - which showed NO haze. Discovery really did look like a comet with a short half degree fan shaped tail (in 7x50B). Water dumping no doubt? Can anyone confirm this or are such mundane matters not logged?

David Moore BSc FRAS, Editor of "Astronomy &Space" magazine.

Chairman, Astronomy Ireland, P.O.Box 2888, Dublin 1.

Date: Mon Feb 6 09:53:31 1995

From: NASEP007@sivm.si.edu (Geoff Chester)

Had a wonderful sighting of Discovery and MIR this morning from the frozen steps of Alexandria, VA. It was about -13C, clear as a bell (I think the atmosphere was frozen on the snow...) so much so that at first I mistook mistook Arcturus for Mars (hadn't had that first cup of morning coffee, either!) Picked up Discovery in the handle of the Big Dipper, and as it neared the zenith, saw MIR following about 30 degrees behind. Discovery was about mag -1.5 whe I first saw it, but it faded quite dramatically to around +2.0 during and after culmination. MIR, on the other hand, remained very bright through the zenith passage, fading from about -2.5 down to -1.5 before I lost it behind the roof line. Too bad it was so cold...the local media here were alerted to the event, but the weather itself seemed more news- worthy!

Date: Mon Feb 6 13:06:00 1995

From: DunhamDW@space2.spacenet.jhuapl.edu (Dunham, David W)

Walter, I didn't get this morning's message in time, but using the Sat. afternoon message (which I didn't acquire until late last night), William and I saw both objects this morning (he was excited to see two "spaceships"). Joan had already gone to excercise class so she missed it; she left before I could wake up to tell her. The following object, maybe half a minute or about 20 deg. behind the first, was a mag. or two brighter, but I'm not sure which was which. The brighter was probably as bright as Jupiter, maybe a little brighter, but I don't think as bright as Venus; after crossing the zenith, we couldn't see them out the east windows, so they must have gotten much fainter with the unfavorable phase angle. We stayed in the house; our outside thermometer read +1 deg. F.

Date: Mon Feb 6 14:46:57 1995

From: dk058@cleveland.Freenet.Edu (Walter Nissen)

The latest elsets I have for Mir and STS-63 suggest that for this morning's pass Mir was leading Discovery by almost a minute and that Discovery culminated at 11h 37m 2s, in close agreement with Steve Miller's report. For tomorrow morning the Mir pass will come about 57 minutes earlier and culminate at 41 degrees over azimuth 32 degrees (This is for Washington, DC. Both Rockville, MD, and Alexandria, VA, are near the Washington Beltway.).

Date: Mon Feb 6 22:50:30 1995

From: apertur@aplcenmp.apl.jhu.edu (E Roelle curtis wayn)

This morning (Monday) I observed the Shuttle and Mir from my NW-facing balcony on the front of the house. Shuttle rose first, and Mir was about a minute behind it. Both passed nearly through the zenith and then faded as they headed East, due to reduced sunlit surface being visible.

I use a handy little program called "Trackstar" along with Kelso's element posts on sci.space.news to calculate my ephemeris. Then after the show I rush my kids back in and show them the swiftly moving ground path using the "instant track" program. I put on a little show for them. Tonight at bedtime they asked me to check the ephemeris and then asked to be woken up for tomorrow's 5:30ish performance.

Curt

Date: Mon Feb 6 22:45:48 1995

From: yamada@spaceb.ysc.go.jp (Yoshiro Yamada)

I observed STS-63 and Mir around 20:49 UTC on Feb. 6 (05:49 JST on Feb. 7) from Yokohama (35.4N, 139.6E). They looked together like one bright star, mag -1 or brighter, with the naked eye (I could not use binoculars, occupied with photographing).

No bright objects were observed some minutes ahead/after.

Date: Tue, 7 Feb 95 04:05:00 UTC

From: jay.respler@genie.geis.com

During the Discovery launch, there was constant visibility of the exhaust at first. After fading, Discovery flashed back into view several times. Does anyone know the cause of these pulses? After MECO, are the engines fired again for short bursts to refine the orbit?

At 5:01 this morning, I just missed Mir, but did see Discovery in the NE at 20 deg elev. A much better view was at 6:36am. The sky was bright with only 1st mag stars visible, when Mir came by in the SW, 55 deg elev, about mag 1. Followed in 1/2 minute by Discovery, mag -1 or -2. I would like to have seen them during rendezvous, but this was nice anyway.

Date: Tue Feb 7 09:04:38 1995

From: NASEP007@SIVM.SI.EDU (Geoff Chester)

Now that I have thought about it (The coffee finally kicked in :-) ) Discovery would have been the trailing object Monday morning. They were still chasing MIR from a lower orbit, therefore they were moving faster rela- tive to MIR. In order to intercept on the subsequent orbit they would have had to approach from below and slightly behind. From what I have gleaned they were also in a payload bay-to-sunward attitude to keep the leaky thruster warm, so that's why it appeared so bright and didn't fade appreciably until well past the zenith.

Now that they are separate again, Discovery should drop into a lower and fas- ter orbit to retrieve the SPARTAN, so it will lead MIR in the next few appa- ritions.

Time for more coffee!

Date: Mon Feb 6 19:28:15 1995

From: wtba@qmgate.eci-esyst.com (Bill Bard)

Jay Respler wrote : During the Discovery launch, there was constant visibility of the exhaust at first. After fading, Discovery flashed back into view several times. Does anyone know the cause of these pulses?

I've heard of people seeing that on previous launches. What it probably was is the thrusters on the shuttle firing to separate it from the external tank. Once it was separated, there could have been additional firings to stabilize the shuttle's attitude and provide additional separation velocity.

Date: Mon Feb 6 19:44:09 1995

From: wtba@qmgate.eci-esyst.com (Bill Bard)

Yoshiro Yamada wrote :

They looked together like one bright star, mag -1 or brighter, with the naked eye ( I could not use binoculars, occupied with photographing).

I believe the shuttle and Mir were approx 100 to 150 meters apart at the time. They were supposed to seperate at 21:13 UTC on Feb 6. With binoculars, you probably could have seen two seperate objects depending on their positions.

Date: Tue Feb 7 09:29:11 1995

From: trw@aluxpo.att.com (Thomas R Wik)

Walter, It was good to talk to you again on Sunday. I did take advantage of the information you supplied to observe Mir and Discovery. I was able to see them in a perfectly clear sky - right on schedule. I was surprised at how bright they appeared toward the Northwest and how much they seemed to dim as they moved toward the gathering dawn in the Southeast. By the time they approached Venus, they were extremely difficult to see.

Tom

Date: Tue Feb 7 09:43:40 1995

From: bishop@sn520.utica.ge.com (David W. Bishop)

At 5:38 EST this morning I saw Discovery and Mir in a perfect pass, 70 degrees above the Southern horizon, going W to SE. We had some clouds on the horizon, but conditions were very clear.

Discovery (brighter of the two) was about 12 degrees in front of Mir. Brightness of Disovery at max was about the same as Venus. Mir was about 2 mags dimmer. No other objects were sighted nearby. I was able to track these two till they almost hit the horizon. Discovery dimmed to about mag 4.0 at about 5 degrees about the horizon.

Here in Northern NY it was about 20 below 0 F ( -30 C ) and a bit brisk. That makes the atmosphere thinner as it starts to solidify.....

Date: Tue Feb 7 21:00:13 1995

From: wats@scicom.alphacdc.com (Bruce Watson)

I, too, observed Mir and Shuttle Discovery from Denver, Colorado during the predawn hours of the morning of Feb 6 about 13:07 UTC. Mir (at +1 mag) was leading Discovery (at -1 mag) by 36 seconds of time (270 km?). Except for the difference in spacing, the sight was reminiscent of STS-27 on the evening of Dec 2, 1988 where Atlantis and Lacrosse 1 were visible. It looked like a wide double star crossing the sky. Yesterday, it looked like two planets moving far too quickly across an ecliptic.

This is only the fourth time I've observed the Shuttle. Now that it has been decided to assemble Space Station Alpha in the 51.6 deg orbit, we, at higher latitudes will see the Shuttle (and the station) more often.

Date: Thu Feb 9 10:00:36 1995

From: pnorloff@bbs.os2bbs.com (Pete Norloff)

Just wanted to drop you a note to report the sighting of Discovery and Mir this morning. Watching through a front window in our house (the temperatures being in the teens this morning) Discovery appeared overhead at 5:20 and traversed toward Venus, disappearing into the brighter sky over the horizon in Fairfax, VA. Two minutes later, Mir appeared just slightly to the south of where we first spotted Discovery, traversing a parallel path toward Venus and again disappearing into the brighter sky. Mir appeared to us to be about twice as bright as Discovery.

Thank you for the info on spotting the spacecraft!

Date: Thu Feb 9 18:20:00 1995

From: DunhamDW@space2.spacenet.jhuapl.edu (Dunham, David W)

Walter, Joan and I saw Discovery and Mir this morning. Discovery passed a short distance to the left (north) of Venus while Mir, following 1 - 2 minutes later, passed a short distance to the right of Venus. Mir brightened to about 1st mag. as it approached Venus, then faded at the low altitude; Discovery was seen in binoculars as it passed the planet. I also observed the ZC 654 graze at Bel Alton, and timed 4 D's and 4 R's. Three others tried at different locations; I haven't heard their reports.

David

Date: Thu Feb 9 21:01:33 1995

From: apertur@aplcenmp.apl.jhu.edu (Curtis Roelle) Dear Walter, We've been able to see Mir/Discover for five days straight. Last night I handed out ephemerides for Thursday and Friday at our Astronomy club meeting, and have heard from two others who saw it this morning.

Yesterday a fellow at work came up and excitedly asked if he possibly sighted the Mir/Discover combo in the morning around 6:15, I said yup and gave him a schedule for Thursday and Friday. I asked him how he heard about it and he said that he didn't - he just happened to be looking out the window at the right time and saw them both, with Discovery trailing about 20 seconds behind. Talk about luck!

Curt

Date: Thu, 09 Feb 1995 09:23:58 -0500

From: M_seeds@ACAD.FANDM.EDU (Janet Seeds)

Walter,

This morning my wife, daughter and I saw both the shuttle and Mir emerge into sunlight. Observing from Lancaster PA we saw the shuttle as a 2nd to 3rd magnitude object emerge at about 5:22 at about 60 degrees above 140 degrees. The shuttle dissappeared over the horizon shortly before we saw Mir emerge following roughly the same track. Mir was brighter.

Since we are about 100 miles north of Washington DC, I worked out rough altitude and azimuth from your numbers. I over estimated the altitude of the spacecraft in miles, but it didn't make much difference. If you have the numbers handy for these sightings, it would be helpful to know the altitude of the object in miles. Then I could zero in from my location.

Judging from the morning news, the shuttle astronauts must have been closing with and preparing to grab the Spartan satellite as we watched them emerge into sunlight. They would not have grabbed it in darkness, and the 7 am news said they had "just" latched onto it, so it was probably between 6 and 7 am that they reached out to it with the arm. My daughter and I did a quick calculation in our heads on the way to school and figured out that the Spartan satellite should have been at least 7 magnitudes fainter than the shuttle assuming equal albedos and rough dimensions - well below the eye limit.

Thanks again for sending these along. I am using them to show my math-whiz-know-it-all-daughter that things like Arc Tan functions are useful. I am also offering to pass these predictions on in a timely fashon to the teachers in a local high school, so we will see how tough they are!

Mike Seeds

Date: Thu, 9 Feb 95 10:00:36 EST

From: Pete Norloff

Just wanted to drop you a note to report the sighting of Discovery and Mir this morning. Watching through a front window in our house (the temperatures being in the teens this morning) Discovery appeared overhead at 5:20 and traversed toward Venus, disappearing into the brighter sky over the horizon in Fairfax, VA. Two minutes later, Mir appeared just slightly to the south of where we first spotted Discovery, traversing a parallel path toward Venus and again disappearing into the brighter sky. Mir appeared to us to be about twice as bright as Discovery.

Date: Sat Feb 11 08:56:59 1995

From: dk058@cleveland.Freenet.Edu (Walter Nissen)

The appendix is the file MIR.TLE from the OIG RBBS at oig1.gsfc.nasa.gov, augmented with hyphens to note the passing of days.

Note the behavior of the successive values of the mean motion. With the exception of the values in elsets #916, 917, 919, the pattern of gradual increase roughly in agreement with the values of ndot2 is unremarkable. (Actually this very slightly oversimplifies the agreement). Does anybody believe that the values given are real? That Mir was boosted up and then back down?

Daniel Costanzo (and also one other observer) have reported observing the (presumably) Spartan package in the vicinity of Discovery. He calls it the "flying double" and reports the Spartan about 3 mags fainter than Discovery. I looked very carefully on the one fairly clear morning here, 950208, and could not locate the Spartan nor any fuzz in 7x35s. Many reports come from North America and the fringes of the North Atlantic of Mir and Discovery making very bright passages moving in tandem. Three different people reported from the Washington, DC, area that Mir brightened as it approached Venus (neared the horizon). Some report how very impressive it is to see the whole manned space effort in one field of view, or one sky. I see the future there.

Discovery landed safely.


Mir
1 16609U 86017A   95032.84485132  .00006600  00000-0  90425-4 0  9129
2 16609  51.6477 116.0135 0001369 199.3616 160.7324 15.58726545511799

1 16609U 86017A   95034.06297984  .00006148  00000-0  84639-4 0  9139
2 16609  51.6474 109.9045 0001144 214.6193 145.4706 15.58742067511981

1 16609U 86017A   95035.21699064  .00004823  00000-0  67772-4 0  9140
2 16609  51.6471 104.1138 0001078 224.0968 135.9939 15.58749641512145

1 16609U 86017A   95036.24276677  .00005128  00000-0  71618-4 0  9159
2 16609  51.6471  98.9656 0001058 225.4835 134.6064 15.58762091512303

1 16609U 86017A   95038.16608943  .00007354  00000-0  10000-3 0  9168
2 16609  51.6463  89.3198 0000535 269.7333  90.3589 15.58728736512603

1 16609U 86017A   95038.42253798 -.00034707  00000-0 -43768-3 0  9173
2 16609  51.6465  88.0321 0000509 262.3694  97.7156 15.58711127512640

1 16609U 86017A   95039.12775808  .00019426  00000-0  25278-3 0  9199
2 16609  51.6460  84.4903 0000694 308.8415  51.2516 15.58772059512751

1 16609U 86017A   95039.25598067  .00011090  00000-0  14726-3 0  9200
2 16609  51.6461  83.8459 0000831 296.4901  63.6005 15.58764259512771

1 16609U 86017A   95040.21763988  .00006882  00000-0  93849-4 0  9212
2 16609  51.6467  79.0196 0000619 272.6778  87.4140 15.58773343513009

1 16609U 86017A   95041.24340136  .00006214  00000-0  85323-4 0  9231
2 16609  51.6464  73.8702 0000628 270.3907  89.7014 15.58786406513166

Date: Sun Feb 12 01:51:10 1995

From: phunter@ion.apana.org.au (Peter Hunter)

STS-63 sighted 10th Feb 1915(L) 0715(UTC) against the last of a tropical sunset from the beach at Nadi, Fiji. First seen Az 300 El 30 (max elevation according to Traksat/Star Chart mode running on my notebook beside me). STS-63 followed to approx Az 000 El 10.

Mir sighted soon after same track, but dimmer, and not sighted till Az 330 El 20 descending.

Peter Hunter

(normally resident Sydney, Australia, in Nadi for one day).

Addendum by WN:

I believe the analysis in Geoff Chester's latest message is correct and, based purely on geometrical and energy consumption considerations, that it is likely to be correct for many of the forthcoming missions. The shuttle orbiter will chase Mir from a lower and faster orbit, thus appearing behind Mir in the sky. After departing Mir, it will again head lower and thus appear ahead of the space station in the sky.

compiled by Walter Nissen



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