Take the 2-minute tour ×

Can I see the International Space Station (ISS) from the surface with the naked eye? If yes, how can I determine that it really is the ISS?

share|improve this question
Use this free android application to track the current location of ISS. play.google.com/store/apps/… –  sElanthiraiyan Dec 9 at 7:13

7 Answers 7

up vote 22 down vote accepted



  • ISS needs to pass roughly overhead of your location, and

Now, obviously there are other requirements, like e.g. weather (if it's overcast we won't be able to see it through the clouds). And it won't be visible when it's in the Earth's shadow and doesn't reflect any light during the wee hours of the night.



              enter image description here

                  shown in the white circle (Image source: ISS Tracker)



And so on, and I'm omitting part of that answer that isn't relevant to your question to save you the trouble. But it might help you understand the station's movement over our night skies better. Since that question is about the ISS timetables for given coordinates, you might have guessed by now that there are various services on the internet and software that will help you determine when and where to look for it. NASA hosts one of such tools too, on their Spot The Station website. Or perhaps ISS observation tool on Astroviewer.net that I find fairly straightforward to use. And there are many others.

As for identifying it from among other visible objects, the easiest is simply knowing that it should be about as bright as some of the brightest stars and planets on the night's sky (depends on exact angle of their solar panels to the Sun and your observation point, it's distance and atmospheric conditions, but it doesn't get much brighter than, say, planet Venus), with major difference that it won't follow the sidereal time (its apparent motion won't follow the rotation of the Earth), so it will move much faster than the stars, it won't have location lights flashing on it like planes do, won't produce any noise, no airplane contrails behind it, and it won't change course and/or speed. Average observable time from a single location during one of its orbits will be roughly 3 minutes, before it again disappears over the horizon. And if you first observed it rising and setting close towards southeast or it shot straight over you, chances are you'll be able to observe it once more some 90 minutes later rising from the southwestern direction.

There are also some softwares that could help you confirm it's indeed the ISS, I personally use Sky Map + for my Android smartphone. It is free and uses your phone's internal gyroscope, compass and/or GPS to enable you to follow and identify visible features of the night's sky (can be filtered by type) by holding the phone in front of you and towards the observed object. Simple.

share|improve this answer
Under the right conditions, the ISS is theoretically daylight-visible. Peak brightness is around magnitude -5.9, while the daytime sky is around magnitude -4 (en.wikipedia.org/wiki/…). –  Mark Mar 19 at 5:17
@Mark: Those "right conditions" can't exist, because the following 3 conditions are all required: Sun high in sky, ISS above horizon, Sun strongly illuminating the earth-facing side of the ISS. –  Ben Voigt Mar 19 at 14:02
I share your answer in /r/Space on Reddit. I hope it's gonna be helpful for some guys out there –  Zoltán Schmidt Apr 24 at 23:29
@KeithThompson OK, duly noted. I'll update it then. Thanks! –  Noordung Nov 7 at 19:04
@KeithThompson And so did I and I wrote the darn thing LOL –  Noordung Nov 7 at 20:08

Yes, you can. When it is illuminated by the sun, it is brighter than any star and moves with a quite high speed across the night sky which makes it quite easy to spot. Because of its low orbit it can only be seen from a small area at any given time, but thanks to its strongly inclined orbit it regularly passes over most inhabited areas of earth. You can check its current position and when it will have its next overpass near your location on Heavens Above. First set your location and time zone, then go to the subpage of the ISS to check when it will do its next overpass near you.

share|improve this answer
You see lots of other satellites as well! Heaven's Above will show you some of the brighter ones. Also try to catch an Iridium Flare; a brief, very bright (sometimes brighter than the ISS) reflection of the sun off solar panels on Iridium satellites. –  Stu Mar 19 at 18:37

Yes, you can see the ISS with the naked eye under certain conditions. As for identifying it, it will be quite bright compared to stars and it will be visibly moving. It will not have flashing anti-collision lights like a plane, it will be a more-or-less constant intensity bright light and will appear to be moving across the sky faster than a cruising jet airliner would appear to be moving.

To know what it's going to be visible at your location, you can sign up for e-mail or text message notifications directly from NASA at Spot the Station.

The conditions for seeing it are:

1) It must be night (otherwise the sky will be too bright to see it.)

2) It must be flying relatively close to directly over your location.

3) As with viewing anything else in outer space, the sky at your location must be relatively clear during the flyover.

4) It must be either shortly before dawn or shortly after dusk (well, for most locations, at least.) The reason for this is that, by definition, night occurs when your part of Earth is facing away from the sun, yet the sun must be hitting the space station for it to be visible with the naked eye. Once it passes into the shadow of the Earth, it will disappear. The closer the flyover is to dawn or dusk at your location, the longer you'll be able to see the ISS for this reason. It will usually pass into the shadow of Earth (and, thus, disappear) before it actually sets on the horizon. The longest visibilities tend to be about 6 minutes.

Flyovers of the space station will occur roughly 90 minutes apart, though usually only one flyover will be visible to the naked eye per morning or night, due to the aforementioned reason of it needing to be close to dawn or dusk to see it.

share|improve this answer

I signed up for alerts at spotthestation.nasa.gov. There you can register your location and have alerts sent to your email when the space station will be passing over you. It also tells you what part of the sky it will first appear and will it will disappear along with the angle above the horizon and the duration it is visible. Here is a sample of what the email will contain.

Time: Fri Mar 14 5:53 AM, Visible: 2 min, Max Height: 73 degrees, Appears: SSE, Disappears: NE

Hope this helps. Happy viewing

share|improve this answer

Here is an example photo of the ISS passing overhead near sunset in Tübingen, Germany:

super wide angle multiple exposure shot of ISS overhead

The line is dashed because it is a long series of exposures that were then stitched together. Here is a link to a video of the same event. Credit: © T. Credner & S. Kohle, AlltheSky.com (use for private and non-profit educational purpose only).

share|improve this answer

Yes it is even possible over your smartphone to locate the exact direction, latitude, longitude if weather permits.

  1. Download iOS application ISS Spotter , it will show the exact date and time when it is passing over your loaction (weather permits).

    1. Download sky viewer, where you can get the mere exact direction to look.
share|improve this answer

I just witnessed ISS with naked eye! It appeared for roughly 35-40seconds and then disappeared! Location: Islamabad, Pakistan The weather here is clear.

share|improve this answer

Your Answer


