# Night sky timelapse - SO MANY METEORS?

I have really little knowledge of Astronomy in general. Last Monday, I tested my new camera by doing a Night-Sky timelapse. After a little post-processing, i noticed dozens of light streaks going in all directions.

I can't tell if those are meteors, airplanes or satelites.

Could you help me out? This is the video: https://www.dropbox.com/s/y4jfiua8blzanpe/test2.2_h264-420_1080p_25_MQ.mp4?dl=0

• Location: Central Switzerland
• Camera direction: Straight south
• Camera inclination app. 30°
• Date: 19.6.-20.6.
• Time: app.22:57-02:50

Thanks a lot guys, Marc

• Mp4 compression added some weird flickering and there is a bump in the middle of the video, but I should manage to smooth that out later on... Jun 23 '17 at 12:49
• Probably satellites. Meteors usually last less than a second. I don't know the timescale of your (very nice) timelapse, but it looks to me like they move rather slowly across the sky. Also, meteors tend to come from the same direction.
– pela
Jun 23 '17 at 13:08

Some are probably satellites, others are probably planes. Meteors are highly improbable in this case. Reasons:

• There are no notable meteor showers visible at your given location and time.
• Even if there were, as someone in comments pointed out, meteors tend to appear as if they all came from the same point in the sky. This is clearly not the case
• Most meteors occurrences are very brief. A meteor lasting more than a few seconds is very rare (some well-known showers are exceptions to this, but they are certainly not active at your given time). Hence, when compressing a period of four hours into twelve seconds, one second in real-time gets compressed to less than $0.001$ seconds. Most captured meteors wouldn't be appear for that long on your timelapse.
• Although the difference between airplanes and satellites is hard to spot on a timelapse (the main difference is that planes have blinking lights, whereas satellites do not. The frequency of the blinking is too fast to be visible on this timelapse), most airplanes don't disappear halfway through the sky. They would appear at the horizon and remain visible until they disappear behind the horizon again. The visibility (and luminosity) of satellites, however, depends on the orientation of the satellite, which usually causes a satellite to 'disappear' mid-flight. Some tracks on your timelapse do cover the entire width of the screen, and those are probably planes
• If all of these are satellites, then that would be the highest amount of satellites I've ever seen on a time span of four hours.

If you want to further track their origin, there exists software for both airplanes and satellites that can tell you exactly which ones will be visible at a given location and time. A quick Google search will give you plenty of suggestions. On my smartphone, I use an app called heavens-above to be aware of satellites passing by on an observing night, but I don't think it can calculate back to the past.