1. The satellite needs to be passing overhead at an angle where you can see it, and clear skies etc.
2. The sky needs to be dark enough to see it (so twilight or night)
3. The satellite needs to be illuminated by the sun.
4. The satellite needs to reflect enough light that you can see it.
Basically this happens just before sunrise, and just after sunset. So the ground and sky are dark (allowing you to see through the atmosphere), and the satellite - being at high altitude - is still illuminated.
As they pass overhead, you can often see them suddenly vanish as they pass into the Earth's shadow.
The International Space Station is a good one to find, as it's quite bright (very large).
There are various websites and apps; some phone apps use the GPS and magnetometer to show you what direction and time to look, and a search tool to look for visible objects at your location. It used to be really good with the old Iridium satellites, which gave a bright flash due to their large flat antennas.
> Basically this happens just before sunrise, and just after sunset.
I've seen plenty of satellites in the middle of the night, from very dark areas (wilderness). They look like stars, only they move more quickly. These observations go back a decade, at least.
I was mostly referring to the brightest things like the ISS, Starlink and (formerly) Iridium satellites, which are in low Earth orbit.
Higher orbits are visible for longer, due to the angles involved: because they're so high, such satellites can remain illuminated with the Sun further below the horizon. The Moon is the most extreme example: it's almost never in Earth's shadow.
To me, they look like little white dots moving across the sky. Brightness can change as they move too. It'll start off bright and then as it goes away it eventually disappears entirely. Since I usually sit in the same position in the hot tub, I've come to notice that I usually see one of them cross a pretty specific path from north to south, so I've gotten used to looking in that part of the sky as I'm sitting there. It happens so frequently, I get a little disappointed if I don't see one!
Planes are similar, but tend to have flashing or colored lights and obviously aren't as far away.
I'm in a big city, but close to the ocean so I have a bit less light pollution. The city is also heavy military, so that could be part of the frequency.
Update: if you're near any of the spacex launches, you can watch the rocket too. I'm house sitting in Irvine, CA and saw the Monday launch go right near the house. Amazing to watch the plume from the rocket!
Just throwing this out there, but has anyone else seen 'formations' of satellites? I've only seen them once but there were about 5 to 10 (it was a while ago) of what I'm assuming are satellites moving in a line formation at high speeds across the night sky. They're too distant and too fast to be planes so I'm assuming they are some sort of military formation of satellites?
That's often a recently launched StarLink formation -- the bunch up in a line when deployed, and have to be maneuvered over several weeks to spread out and take different orbits.
I don’t know how you would know that. People are very bad at seeing distances at these scales.
If they were indeed satelites they could be starlink satelites. They are put into orbit as a bunch together and then they spread along their orbital path as they take up their position.
If you could recall more details then maybe we can figure out more exactly what this might have been. (Such as where you were, which direction you were looking at, when did this happen, how fast did they cross the sky and how far the dots were from each other. Were the line spread in the direction they were moving or sideways?)
I saw ISS in formation with visiting spacecraft a couple times - once with Space Shuttle back in the day and at least once with Dragon. Looks pretty interesting. :)
My impression was that you can only see them as they reflect sunlight in your direction. As the angle formed between you, the satellite and the sun changes, you will first not see the satellite, then see, then not see it again.
And of course, if it is 3am, and there is no sunlight at any altitude because the sun is on the other side of the world, no satellites are visible.
My tip is that the very central part of your field of view has worse night vision than the rest (trading off for higher resolution instead), so if you spot something moving in your peripheral vision, don’t try to look straight at it or it’ll disappear; instead, look slightly to the side, and it’ll be easier to see (although maybe blurrier).
You probably just thought it was a star or a plane. They move but relatively slowly (even a fast LEO sat will cover the sky in about 5 minutes). They look just like a star apart from moving slowly. Depending on angles they can look pretty dim, especially the latest SpaceX sats. But the ISS is usually really bright because it's so huge and technically it's also a satellite.
You can tell them apart from a plane because they don't flash.
Edit: But yes there are several conditions that need to be met to see them like the other posters have mentioned. But every clear night near dusk or dawn you will see sats for sure. There are just so damn many in LEO now.
It depends where you live certainly - if you live close to a big city you will probably never see them. But there are places - like New Zealand - where you can see them fairly often. There are some online trackers you can use.
The easiest satellite to see is the ISS. NASA provides times when it can be seen from any given place. I subscribe to the SpotTheStation mailing list.
In general, you can see a satellite when it is overhead and illuminated by the sun. In the evening, it will appear in the west, moving towards the east ( almost all satellites go this way, not just ISS ). As it goes farther east, heading towards darkness, it will fade away. The ISS is bright enough to see a reddish tinge as it passes through sunset light.
Yeah. With Starlink satellites, you need a lot of luck with the conditions to see them. I've seen them a handful of times and I'm in a relatively dark sky location.
ISS is often visible in the middle of the day even in bright midday Southwest sun, if you know where & when to look.
It takes several minutes for your eyesight to adjust enough to spot them with the naked eye. You can use websites to know when one is likely to pass overhead. Choose a suitable time (see: everyone else, basically right after dusk), and then lie down and stare up about 15-minutes ahead. Mushrooms are optional, they increase the chances of seeing something but decrease the chance that what you saw was real.
https://james.darpinian.com/satellites/ Put in your location and it will tell you when and where to look at the sky to see one. Works great for me and hopefully it will work for you.
If the seeing is good it's actually possible to spot up hundred satellites with the unaided eye. Due to light pollution, it's unlikely to spot one in most places, though. The ISS at least should be easily visible due to its size, even in places that aren't particularly dark.
1. The satellite needs to be passing overhead at an angle where you can see it, and clear skies etc.
2. The sky needs to be dark enough to see it (so twilight or night)
3. The satellite needs to be illuminated by the sun.
4. The satellite needs to reflect enough light that you can see it.
Basically this happens just before sunrise, and just after sunset. So the ground and sky are dark (allowing you to see through the atmosphere), and the satellite - being at high altitude - is still illuminated.
As they pass overhead, you can often see them suddenly vanish as they pass into the Earth's shadow.
The International Space Station is a good one to find, as it's quite bright (very large).
There are various websites and apps; some phone apps use the GPS and magnetometer to show you what direction and time to look, and a search tool to look for visible objects at your location. It used to be really good with the old Iridium satellites, which gave a bright flash due to their large flat antennas.
I remember chasing one of the iridium flares and it was very bright, even during the day
> Basically this happens just before sunrise, and just after sunset.
I've seen plenty of satellites in the middle of the night, from very dark areas (wilderness). They look like stars, only they move more quickly. These observations go back a decade, at least.
I was mostly referring to the brightest things like the ISS, Starlink and (formerly) Iridium satellites, which are in low Earth orbit.
Higher orbits are visible for longer, due to the angles involved: because they're so high, such satellites can remain illuminated with the Sun further below the horizon. The Moon is the most extreme example: it's almost never in Earth's shadow.
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That doesn't seem right, why would they be bright?
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In short: after sunset.
To me, they look like little white dots moving across the sky. Brightness can change as they move too. It'll start off bright and then as it goes away it eventually disappears entirely. Since I usually sit in the same position in the hot tub, I've come to notice that I usually see one of them cross a pretty specific path from north to south, so I've gotten used to looking in that part of the sky as I'm sitting there. It happens so frequently, I get a little disappointed if I don't see one!
Planes are similar, but tend to have flashing or colored lights and obviously aren't as far away.
I'm in a big city, but close to the ocean so I have a bit less light pollution. The city is also heavy military, so that could be part of the frequency.
Update: if you're near any of the spacex launches, you can watch the rocket too. I'm house sitting in Irvine, CA and saw the Monday launch go right near the house. Amazing to watch the plume from the rocket!
Just throwing this out there, but has anyone else seen 'formations' of satellites? I've only seen them once but there were about 5 to 10 (it was a while ago) of what I'm assuming are satellites moving in a line formation at high speeds across the night sky. They're too distant and too fast to be planes so I'm assuming they are some sort of military formation of satellites?
That's often a recently launched StarLink formation -- the bunch up in a line when deployed, and have to be maneuvered over several weeks to spread out and take different orbits.
> They're too distant
I don’t know how you would know that. People are very bad at seeing distances at these scales.
If they were indeed satelites they could be starlink satelites. They are put into orbit as a bunch together and then they spread along their orbital path as they take up their position.
This article has a picture, maybe you can check if it is similar to what you have seen? https://earthsky.org/space/spacex-starlink-satellites-explai...
If you could recall more details then maybe we can figure out more exactly what this might have been. (Such as where you were, which direction you were looking at, when did this happen, how fast did they cross the sky and how far the dots were from each other. Were the line spread in the direction they were moving or sideways?)
I saw ISS in formation with visiting spacecraft a couple times - once with Space Shuttle back in the day and at least once with Dragon. Looks pretty interesting. :)
I guess they disappear as they approach the horizon because the light is spread/absorbed too much by going through more atmosphere?
My impression was that you can only see them as they reflect sunlight in your direction. As the angle formed between you, the satellite and the sun changes, you will first not see the satellite, then see, then not see it again.
And of course, if it is 3am, and there is no sunlight at any altitude because the sun is on the other side of the world, no satellites are visible.
I could be wrong.
I actually see them disappear long before they get to the horizon. My guess is just less reflected light on whatever is shiny on the satellite.
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My tip is that the very central part of your field of view has worse night vision than the rest (trading off for higher resolution instead), so if you spot something moving in your peripheral vision, don’t try to look straight at it or it’ll disappear; instead, look slightly to the side, and it’ll be easier to see (although maybe blurrier).
I can guarantee you you have.
You probably just thought it was a star or a plane. They move but relatively slowly (even a fast LEO sat will cover the sky in about 5 minutes). They look just like a star apart from moving slowly. Depending on angles they can look pretty dim, especially the latest SpaceX sats. But the ISS is usually really bright because it's so huge and technically it's also a satellite.
You can tell them apart from a plane because they don't flash.
Edit: But yes there are several conditions that need to be met to see them like the other posters have mentioned. But every clear night near dusk or dawn you will see sats for sure. There are just so damn many in LEO now.
Some satellites do appear to flash because they are tumbling: https://www.satobs.org/tumble/tumbleintro.html
The flashing of satellites will generally be gentler than the short burst strobing of an aircraft.
It depends where you live certainly - if you live close to a big city you will probably never see them. But there are places - like New Zealand - where you can see them fairly often. There are some online trackers you can use.
I live 10 miles from Boston and I've seen them a whole bunch. I've used https://james.darpinian.com/satellites/?special=starlink
The easiest satellite to see is the ISS. NASA provides times when it can be seen from any given place. I subscribe to the SpotTheStation mailing list.
In general, you can see a satellite when it is overhead and illuminated by the sun. In the evening, it will appear in the west, moving towards the east ( almost all satellites go this way, not just ISS ). As it goes farther east, heading towards darkness, it will fade away. The ISS is bright enough to see a reddish tinge as it passes through sunset light.
Shooting stars go much faster than satellites.
Yeah. With Starlink satellites, you need a lot of luck with the conditions to see them. I've seen them a handful of times and I'm in a relatively dark sky location.
ISS is often visible in the middle of the day even in bright midday Southwest sun, if you know where & when to look.
It takes several minutes for your eyesight to adjust enough to spot them with the naked eye. You can use websites to know when one is likely to pass overhead. Choose a suitable time (see: everyone else, basically right after dusk), and then lie down and stare up about 15-minutes ahead. Mushrooms are optional, they increase the chances of seeing something but decrease the chance that what you saw was real.
https://james.darpinian.com/satellites/ Put in your location and it will tell you when and where to look at the sky to see one. Works great for me and hopefully it will work for you.
It's usually a somewhat like a fast moving little but visible star. Fast as in it would usually cross 1/4 of the visible sky within 20 seconds or so.
You should try to find one once, with the help of an app. It's not that difficult.
If the seeing is good it's actually possible to spot up hundred satellites with the unaided eye. Due to light pollution, it's unlikely to spot one in most places, though. The ISS at least should be easily visible due to its size, even in places that aren't particularly dark.
Even in a city you stand a chance if you've got high walls around you. A courtyard garden for example. Just lie back and stare up.
Probably out in a rural area far enough away from a major city its easier to see them.
The Starlink ones look like Santa's sleigh https://i.imgur.com/4S0vbfY.gif
Nice image. The Starlink V2 are bigger though, so fewer per launch (~15 vs ~60).
Only directly after deployment, though.