UFO's... What do you think?

[JasperFrank]

Given the odds, the nearest advanced civilization is many light years away. Its not they could just pop in to visit, here and there, if it took 4 million years, or so, years to do it. Extra terrestrials are a fantasy. All FTL travel is a fantasy. Good for entertainment, but not real, and not possible if you can not go faster then C. And we can't go faster than C. So... It's just fun entertainment.

 

[Fuddy1952]

Strange many people don't realize that we're arguing all these points with our brain! Correct?
Strange years ago I was in a bookstore where they had a bin filled with high school textbooks for $1.
I picked up one on Geology since my brother is a Geologist. First page said the Earth is 4.5 Billion years old...unless you're Christian then it's 6,000 years old. ????????
So we're discussing things with bias, what we have developed over time, with what we know (told in books, at church, by scientists, opinions, etc) in 2022.
What % of everything do we know?
New discoveries are made daily. Many discoveries were made by accidents (read history).
Years ago I had a few "Course in Miracles" classes with a friend (rip) a philosophy major. During one lesson...BOOM!"...the building shook. Everyone went outside. The instructor asked "what happened?". A bunch of people gave opinions: a drunk driver hit the building, someone wasn't paying attention, ran a stoplight, car mechanical problems, brakes failed...on & on & on.
The instructor said " a car is sticking out of the building", since that's all we know.
How it got there who only knows.

 

[BravoXray]

For whatever reason I remember that light speed 186,282 miles per second. But if you're driving at night doing, say, 100 mph (I do that sometimes ) then turn your headlights on...is the speed of light now 186,282.028 miles per second?

No, it's still 186,282 miles per second. If someone ahead of you had equipment that was sensitive enough, they would see the light from your headlights being slightly blue shifted.
Light and sound both behave as predicted due to the Doppler effect.

 

[BravoXray]

Is light years a measure of distance or time?

Distance.

As defined by the International Astronomical Union, a light-year is the distance that light travels in vacuum in one Julian year.

 

[sd455dan]

When James Web starts taking new infrared pics I am sure there will be more questions than answers, looking even farther back in time than Hubble.

 

[ArlyA]

When James Web starts taking new infrared pics I am sure there will be more questions than answers, looking even farther back in time than Hubble.

Lots further back. I mean LOTS!

 

[MossRoad]

For whatever reason I remember that light speed 186,282 miles per second. But if you're driving at night doing, say, 100 mph (I do that sometimes ) then turn your headlights on...is the speed of light now 186,282.028 miles per second?

To you, no.

To someone standing off to your side as you go by, and measuring the speed of the light beam leaving your headlight, yes.

 

[MossRoad]

For whatever reason I remember that light speed 186,282 miles per second. But if you're driving at night doing, say, 100 mph (I do that sometimes ) then turn your headlights on...is the speed of light now 186,282.028 miles per second?

Theory of Relativity explains it pretty well.
Watch this video starting at 5:50 and it gives a pretty easy example we can all understand.

 

[bcp]

Turn the light on and click your stop watch at the same time, run out a hundred yards or so, stop, wait, click your watch when the light arrives.

How is the speed of light measured?

math.ucr.edu

Bruce

 

[3 Horse Ranch]

To you, no.

To someone standing off to your side as you go by, and measuring the speed of the light beam leaving your headlight, yes.

Actually the speed of light is a constant. An observer would only notice color shift. If I were shining a flashlight at you while travelling toward you at 10 mph under the speed of light you would measure the speed of light at the constant speed, I would observe the light leaving the flashlight at the same speed. You would see the light shifted and I would see the light reflected back from the mirror you're holding shifted red. What varies is time.