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lighthouse1234
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Why is it that I can still use my 10 year old planisphere, if the stars are in motion?
From what moving position?lighthouse1234 said:From that moving position ...
The stars in constellations are so far away that they can be moving tremendously fast and we will not be able to notice it with the naked eye in our lifetime. The nearest star in Orion is Bellatrix, which is 250 light years away. A light year is 5.8 trillion miles. The farthest star in Orian is Alnilim, which is 1360 ly away. So the change in angle will be small unless/until they move very far sideways or up and downlighthouse1234 said:Why is it that I can still use my 10 year old planisphere, if the stars are in motion?
There's a source!lighthouse1234 said:Someone wrote this to me
If I stand far away from the train tracks near my house and watch a train go by, the train appears to move very slowly. If I hold my thumb up it takes about a second for the train to 'cross' behind it. But if I stand next to the tracks the train will cross behind my thumb in a small fraction of a second.lighthouse1234 said:Someone wrote this to me: From that moving position these 'fixed stars' seem to be stationary,
hence are actually moving, even if they seemingly do not.
"There's that guy again, trying to hitch a ride on our train..."Drakkith said:But if I stand next to the tracks the train will cross behind my thumb in a small fraction of a second.
Yes, the stars of the constellations appear to be stationary from our perspective on Earth. However, they are actually moving in space at incredibly high speeds.
We are able to measure the movement of stars through a process called astrometry, which involves tracking the positions of stars over time. This has allowed us to determine that the stars of the constellations are indeed moving.
This is due to the vast distances between stars and the speed at which they are moving. From our perspective on Earth, their movements are too slow to be noticeable, making them appear stationary.
The speed at which stars move can vary greatly, but on average, they are moving at speeds of around 70,000 km/h. Some stars can reach speeds of over 1 million km/h.
Yes, over time, the stars of the constellations will change their positions in the night sky due to their movement through space. However, this change is very gradual and will not be noticeable in a human lifetime.