(10-23-2023, 09:17 AM)HURRICANE!!! Wrote: I'm never figured out how scientists can differentiate between 7 billion years ago and 8 billion years ago.  To a lesser extent, how do scientists know dinosaurs when extinct 65 million years ago.  I mean,  the era of Jesus was only 2,000 years ago so think about how long 65 million years is, much less 8 billion years.

Red shift. Similar to the Doppler effect for sound, light shifts towards the longer red wavelengths the longer it travels. By studying the shift on a spectrum, astronomers can determine how far, and thus how long, light has traveled. 

Paleontologists determine how long ago dinosaurs became extinct by studying fossil beds within geologic strata with known ages. At a certain point dinosaurs bones suddenly stopped appearing in these geologic layers, which coincides with the K-T Boundary, a layer of iridium rich ash deposited around the globe from an asteroid strike.

I read a lot of science stuff.

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