4 ms·
What you describe does sound like a satellite - but it could also be a rocket body. If it moves slowly enough and lasts long enough to for you to show it to ano
by sreevisakh 6y ago
What you describe does sound like a satellite - but it could also be a rocket body. If it moves slowly enough and lasts long enough to for you to show it to another person, it probably is a satellite or rocket body. As mentioned, it also travels straight and shows up close to dawn and dusk. You can get predictions for sighting in your area from Heavens Above (https://www.heavens-above.com/ https://www.heavens-above.com/).
It gets more interesting though. Most satellites have brightness that changes slowly as moves - due to change in illumination. But occasionally, you would find ones which dim and brighten in cycles. This indicates that the object has no attitude control and is tumbling in space. That could be a dead satellite or a rocket body. Rocket bodies are spent rocket stages which loiter in space for a while after completing its mission. Then there are flares. Some satellites (like the old Iridium constellation) occasionally reflect sunlight right at you (unlike diffuse reflections in normal sats). This is a very local event. Some flares can get brighter than any planet or stars.
It's also possible to identify what you are seeing. That used to be my hobby. You would record the time it appears, how high it gets, the direction in which it flies, how bright it gets and when it disappears. With experience, you can get a good enough estimate of the brightness (magnitude) and angles even without instruments. You would then compare it against satellite predictions like Heavens Above to identify the exact object. The one I was thrilled about was a Russian satellite powered by a nuclear reactor (a fission reactor, not a decay battery like RTG). Some of them are still in LEO (https://en.wikipedia.org/wiki/List_of_nuclear_power_systems_in_space https://en.wikipedia.org/wiki/List_of_nuclear_power_systems_...).