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deanuser
2010-Jul-21, 06:18 PM
Hello All,
I know there is a simular thread on here but I could'nt find it again after becoming a member.
About a week ago when we had clear skies around 11:30, me and 3 friends were star gazing when we all noticed a star begin to move, we all kept out attention on it for around 3-4 minutes untill it got smaller and smaller and disapeared into the the blackness. the colour was EXACTLY like a star the colour was consistant the rst o the stars with no flickering or flashing it not dissapear and re-appear it stayed solid like a star. I have seen satelites move and they move a lot quicker that was the only explanation I could give was the star decided to relocate, it was weird. . at a scaled down speed it appeared to be doing about 10-15mph Any Idea? Many Thanks
Dean.

antoniseb
2010-Jul-21, 06:43 PM
It could have been a satellite in a higher orbit, so its apparent speed across the sky to you would seem slower.

IsaacKuo
2010-Jul-21, 06:57 PM
About a week ago when we had clear skies around 11:30,
What city were you viewing from, and do you remember where in the sky it was? It may be possible to identify what you saw using Heaven's Above (http://www.heavens-above.com/).

me and 3 friends were star gazing when we all noticed a star begin to move, we all kept out attention on it for around 3-4 minutes untill it got smaller and smaller and disapeared into the the blackness. the colour was EXACTLY like a star the colour was consistant the rst o the stars with no flickering or flashing it not dissapear and re-appear it stayed solid like a star.
Do you mean it got dimmer and dimmer, perhaps? It doesn't make sense for it to appear smaller and smaller if it looked like a star, because stars are already pinpoints.

Do you remember if it twinkled, like a star?

Jens
2010-Jul-22, 01:40 AM
About a week ago when we had clear skies around 11:30, me and 3 friends were star gazing when we all noticed a star begin to move, we all kept out attention on it for around 3-4 minutes untill it got smaller and smaller and disapeared into the the blackness. the colour was EXACTLY like a star the colour was consistant the rst o the stars with no flickering or flashing it not dissapear and re-appear it stayed solid like a star.

Just FYI, it is not possible that it could have been a star. Stars are much, much too far away from us to be able to move at a speed sufficient to make them appear to be moving like that. It has to have been something much, much closer. Plus, stars have no way to suddenly accelerate, because they lack engines of any kind. So you should be thinking a plane or satellite or something nearby.

astromark
2010-Jul-22, 07:27 AM
To follow this line of thought... There are many things that it could have been... none of them are stars.

from a very high altitude satellite moving into sunlight., or just a weather balloon.

Angled correctly the solar panels of many orbiting objects could display as you saw... or a military aircraft...

mugaliens
2010-Jul-22, 08:05 AM
...the colour was EXACTLY like a star

Or starlight from the sun as reflected off a satellite.


the colour was consistant the rst o the stars with no flickering or flashing it not dissapear and re-appear it stayed solid like a star.

Satellite reflections are often consistant, depending upon the satellite. The ISS is rock-solid.

Jeff Root
2010-Jul-22, 02:41 PM
Although I think the description in this case clearly indicates that
what was seen was a moving satellite, other, not-so-very-different
sightings evidently ARE stars. The "autokinetic" effect can easily
make a lone point of light, such as a bright star, appear to move
around against a dark background of dimmer stars. That seems
to be the explanation for many sightings.

-- Jeff, in Minneapolis

NEOWatcher
2010-Jul-22, 02:49 PM
The "autokinetic" effect can easily
make a lone point of light, such as a bright star, appear to move
around against a dark background of dimmer stars.
Along with that, a light scattering of teeny clouds could do that too. It's fooled me a few times until I looked long enough.

deanuser
2010-Jul-23, 01:23 AM
it was in SE area bexleyheath. the object did not flash or twinkle ater around 2 and a half mins o it moving slowly it seemed to speed up and out untill I could not visibly see it any more. I am not very educated about knowing what area it was seen and which way it headed all I know Is rom where I was laying it started to move east slowly then dissappeared in a north/east direction. I will look at that site to see i it helps. Thanks or your reply.

deanuser
2010-Jul-23, 01:30 AM
I am glad to say it was not just me that saw it but there were a few stars visible out this night to compare and it was as high (not exactly) as the others, it was not the brightest star or what ever it was. Thanks or you reply. Dean

deanuser
2010-Jul-23, 01:40 AM
but if the it is a moving object then unless the panels were changeing to suit my posistion then the light intesity would not be consistant it would change dissappearing /re-appearing . Do you think a military aircrat would give of any sound in the middle of a quiet night? Also Im pretty sure aircrat that we are familiar with could not fly at that altitude if so this one was silent.
Thanks or your reply
Dean

astromark
2010-Jul-23, 05:42 AM
From what you have been able to tell us...' A star like object that seemed to move across the sky '...

As you have explained as well as you could... I would suggest a satellite.

A web site that can help is 'heavensabove' once there add your location and with a bit of work
you can find most objects that could have been visible to you. At that time...
-----------------------------------and welcome here...

karadan
2010-Jul-23, 08:28 AM
From personal experience, the ISS is possibly the best explanation here. It can be as bright as Venus in the sky and takes roughly 3 - 4 minutes to cross the horizon depending on its apogee.

fifelad55
2010-Jul-23, 10:14 AM
I have to agree with the consensus and that the object seen by the OP was a satellite - probably the International Space Station.

Persistent cloud cover for the last few weeks has prevented me from looking for it (and the Space Telescope) but the Heaven's Above site recommended above gives a very accurate estimate of when it will be visible from your area.

Alan

IsaacKuo
2010-Jul-23, 01:03 PM
Looking up things on Heaven's Above (http://www.heavens-above.com/), I would guess it was Lacrosse 5 (Wednesday, 11:02-11:16, magnitude 1.8). However, magnitude 1.8 may have been a bit difficult to see depending on the conditions.

At the Heaven's Above site, enter your location and then click on " Daily predictions for all satellites brighter than magnitude: (brightest) 3.5 | 4.0 | 4.5 (dimmest)" -- click on the "3.5". At that point, you can navigate to "Prev. PM" until you get to the night in question. You can click on the listings to see a track of the path through the sky.

mugaliens
2010-Jul-28, 03:27 AM
The "autokinetic" effect can easily
make a lone point of light, such as a bright star, appear to move
around against a dark background of dimmer stars.

Actually, no. The autokinetic effect relies on the lack of any other visual reference. Put simply, our ability to perceive small movements, azimuthly, is very dependant upon referential motion.

Thus, whether bright or dim, a pinpoint against a background of stars will not appear to move, but in the absence of stars, will be perceived as to move.

But not across the sky! The autokinetic effect is limited to small, random motions in the general direction of the pinpoint of light.

It's a common phenomenon affecting pilots, and is thus well-drubbed into our craniums as to what it does, and does not do.

Jeff Root
2010-Jul-28, 05:27 AM
Mugs,

I *did* say *dark* background of *dimmer* stars. With the
notion in mind that the bright star might be visible by photopic
(bright light, color, central) vision, while the other stars might be
visible only by scotopic (dim light, monochromatic, peripheral)
vision. In which case the effect I noticed about 30 years ago
could come into play: Scotopic vision apparently is faster than
color vision. So when the eye moves involuntarily, you will first
see the wide field of dim stars move, and then, a fraction of a
second later, you will see the bright star move. In trying to
make sense of those motions, you will interpret it as the bright
star moving randomly against the fixed background stars.

I figure that is probably included under the autokinetic effect,
along with the effect I discovered. (Yes, I discovered it. No, I
don't think I was the first to discover it. Nor the second, or the
tenth, or the hundredth, or even the thousandth. I'm sure it
was given a name by somebody fifty or a hundred years ago.)

-- Jeff, in Minneapolis