Row of lights moving across the sky

RockOrBog

I saw something 15 mins ago and I'm curious as to what it might have been as I've never seen anything like it before.

It was like 8 or 10 yellow lights, in a straight row moving as one across the sky going very fast. After around 30 seconds it seemed to go out of sight. I'm in NW Mayo and it seemed to be up high in the sky but off to the west.

The sky is very clear here tonight, 29 Jan at around 19.20.

Summer2020

Starlink satellite system

reboot

Interesting, haven't seen these satellites yet,but think I'm right in saying satellites always move in the one direction,and don't normally alter course?

Hey2.Hey2

Satellites can change altitude - the orbit decays a little each time and eventually atmospheric drag starts to be a factor so small boosters are fired to return it to a higher orbit.

But, generally a satellite will not 'alter course' (Noticeably head off in a different direction) as that uses precious fuel. Minor adjustments can be made but that would not be noticeable as it is done over the course of a few orbits.

If something altered its course then it's not a satellite…

Akrasia

Nothing that high up (in orbit) should seem to change direction noticeably to the naked eye in a single movement, at those distances and speeds such a perceptible change in velocity would mean an acceleration of thousands of metres per second

If you see something change direction, it's either much lower than you think, or it's an illusion based on atmospheric lensing, or clouds or other moving objects moving nearby and making it seem like the object has moved, (or it could just be your own head or body has moved)

magicbastarder

there was no mention of them altering course in the OP; not sure why reboot mentioned that?

reboot

https://www.boards.ie/discussion/comment/121978349#Comment_121978349

Sorry for any confusion, I suppose we will see more lights in the night sky in future,and would be useful to understand when we are looking at satellites.

TinyMuffin

why do they always travel from west to east?

65535

I've seen them a few times and the ISS - here is a map and more info on the Starlink Satellites

https://www.space.com/starlink-satellite-train-how-to-see-and-track-it

reboot

https://www.boards.ie/discussion/comment/121982075#Comment_121982075

The Earth rotates anticlockwise.

endacl

https://www.boards.ie/discussion/comment/121691717#Comment_121691717

Elon Musk w*nking his ego into space.

Beeker

https://www.boards.ie/discussion/comment/121982075#Comment_121982075

Not always as some are in polar orbits moving North South. The vast majority of satellites travel west to east to take advantage of the Earths spin when launching. The earth rotates at about 1600 kph at the equator and a bit slower at Kennedy Space center, so launching east from there gives you over 1000 kph before you start.

reboot

To slightly digress , I like some people thought the Sun was closer to us in the northern hemisphere in summer, but when I took the time to look it up its the opposite by 5 million miles,silly me.

The tilt is the answer of course.