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I was camping this weekend away from the city, so my friends and I decided to spend one of the nights watching the sky, since it's impossible to see anything around where we live. After a little while, of staring up, I saw what looked like a star moving. It moved fast, but not a long distance, and various directions and back. It was about the same size of the other stars near by. It was not as bright as other stars though. I stopped looking up for a little bit, to make sure my eyes were seeing things correctly. But then I looked up again I continued to see the light moving. I thought I was going crazy, so I pointed it out to my friend. It took him a little while, but after a few minutes he also saw it. His girlfriend also saw it a few minutes later. My friend brought up something about satellite reflections and other theories, but we have no idea what we saw.

So what could it be?

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    $\begingroup$ Moving continuously in a straight line: satellite. Changing direction and/or changing speed: airplane (or maybe firefly). All of these are pretty common sights; there's nothing unusual in seeing a satellite passing overhead. $\endgroup$ – Florin Andrei Aug 25 '15 at 1:18
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    $\begingroup$ It wasn't in a straight line. Do planes travel back and forth around the same area? $\endgroup$ – gdaniel Aug 25 '15 at 1:26
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    $\begingroup$ Note stars sometimes do appear to move short distances, simply because our eyes aren't good at tracking isolated points of light. I've seen this effect myself many times, so I'm not doubting your description. Ideally a sketch (made at the time) showing the position relative to nearby stars, telegraph poles, etc. would prove it's not really moving at all... $\endgroup$ – Andy Aug 25 '15 at 16:35
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    $\begingroup$ It might be a plane with its landing lights on, entering a pattern for a landing. Landing lights are a lot brighter than running light and are easy to miss. $\endgroup$ – Howard Miller Nov 3 '15 at 5:23
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    $\begingroup$ I'm voting to close this question as off-topic because it isn't about astronomy. $\endgroup$ – Rob Jeffries Sep 26 '17 at 7:34
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There was a object, apparently flying above you, that you couldn't identify. By definition this is an unidentified flying object. However this does not imply that it was an extra-terrestrial spacecraft.

UFO reports can be explained by a combination of:

  1. Not recognising a known natural object, such as Venus, or unusual clouds.
  2. Planes, drones, Chinese lanterns or satellites.
  3. Optical illusion, dreams or the effects of drugs.
  4. Deliberate falsification.

There is no real way to decide what it was you saw. There are a couple of points in your report that are odd. You describe it as the same size as stars, but less bright. Stars have no visible size, and have many magnitudes of brightness. Your report suggests that you are someone who doesn't regularly observe the sky, and so is likely to be more susceptible to optical illusions and tricks that eyes can play on us.

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    $\begingroup$ Even a distant firefly. $\endgroup$ – Eubie Drew Nov 22 '15 at 22:43
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The League of Lost Causes wrote the definitive How to identify that light in the sky? guide:

enter image description here
Licensed under Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License

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  • $\begingroup$ This doesn't account for objects moving at irregular velocity / direction $\endgroup$ – srgb Sep 10 at 11:52
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Most likely a satellite. They look exactly like stars, but they glide across the sky smoothly.

Airplanes may have multiple light sources, some blinking lights, and you can definitely perceive how low it seems to be: An airplane somewhat seems to come from the horizon and disappear the same way, while a satellite "seems to always be at the same distance from you", like gliding on an imaginary half-sphere or dome of a night sky covering you.

Last summer I went for a night bike ride for 6 hours and during this time, I spotted 12 satellites just by observing. They're a very common thing. This time I got very lucky though, because one of the 12 satellites unexpectedly was something called an Iridium flare and I had never seen one of those in real life before.

There's a lot of man-made space junk orbiting the Earth, some satellites still operated, some not. There's a bunch of satellites known as Iridium, which happen to have a design that includes large, reflective solar panels.
I live in the North so in the summer, the sun only barely goes below the horizon and the summer nights are short. When I'm just in the dark side but an Iridium satellite happens to fly approximately above me, if everything is in a specific angle, the sun from behind the horizon hits the satellite's solar panels, and like a mirror, reflects those rays to the dark side, into a viewer's eyes.
It was my first time seeing that and I must say, it's extremely impressive when you're merely looking at a "moving star", then unexpectedly it grows very bright, brighter than any star in the night sky, and finally reverts back to the normal looking gliding satellite.

Because people are very much aware of all of the space junk that's up there, there are plenty of websites and mobile apps that you can use to see where the most common satellites are at the moment, and, because we know the route of each satellite, as well as the year and location specific data regarding the Earth and the Sun, Iridium flares can also be predicted, like you would predict things like Solar eclipses.

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  • $\begingroup$ Depending upon the satellite geometry, if it is spinning sometimes you can see it as a blinking light as it goes by. The Space Station will also flare. There's a web site where you can put in your location and it will predict where and when to look to see it flare (just like with the Irridium satellites). $\endgroup$ – Dave Nov 23 '15 at 13:06
  • $\begingroup$ @Dave As for website, this is one such page that I know of: heavens-above.com Don't mind the sketchy looking address! $\endgroup$ – user158589 Feb 1 '18 at 12:06

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