A question that we often get regarding our Star Maps here at Twinkle In Time is, “Aren’t the stars just the same all the time?”
Although the the stars are essentially the same, that doesn't mean that the stars you see throughout the year and from different locations on Earth don't change .
Keep reading and we'll explain why.
Our stars and the sun, is estimated to have a lifespan of about 10 billion years. Large stars that burn out faster still have an expected lifespan in the tens of millions of years. That means that new stars aren’t formed often, and existing stars stay visible for a very long time.
As for movement, the stars are technically moving, but they are so far away that their movement is not detectable by the naked eye. What doesn’t change is the stars' positions in relation to each other. That is why constellations, recognizable patterns of stars, exist and have existed and been used for thousands of years. An example of this is a cave painting discovered in France from 17,000 years ago depicts the constellation that we know as Taurus, the Bull.
What does change is the rotation of earth, both on its axis and around the sun.
This is why each Twinkle In Time custom Star Map will have a different view of the stars. As we take our 365 day trip around the sun, our view of the stars is constantly changing, but not much. Only about 1° per night, but over time that change begins to add up.
Imagine you’re on a road trip and next to the road are telephone poles. They seem to zip by quickly, but the mountains in the distance appear to not be moving at all. In reality, your view of the mountains is changing, but at a much slower rate because of your distance from them.
Give it an hour or two, and the mountains will look noticeably different. The same is true of the stars. Nightly, you may not notice much of a difference, but if you give it a few weeks or months, the stars will look noticeably different.
The other factor that can change your view of the stars is your location on Earth.
If you stand up and look at an area of the room that you’re in, you’ll have one view, but if you take a few steps to the side, your perspective will change slightly. The objects that you were looking at are still the same, but your view is slightly different.
The more you move, the more your perspective changes. Locations on Earth that are close to each other are going to have a similar view of the stars at night, but the further those locations are from each other, the more unique two Star Maps will be.
Those are the reasons why even though the stars don’t change, every Custom Star Map from Twinkle In Time is entirely unique.