Astronomy

Quote: FrGamble

I know lots of stuff about the universe, but I have absolutely no way of proving or even knowing how to go about proving it.

I'll bite, what do you know about the
universe you can't prove? If it's that god
created it, you don't know that, you're hoping
it and of course it can't be proved.

BTW, it's the little things.

History is filled with details which are often overlooked. When you run across them, though, sometimes they unlock a nagging mystery.

Consider relativity. We all know the speed of light in a vacuum is the fastest speed any object can have relative to any other. This has been proven mathematically and experimentally numerous times. Yet, how the hell did Einstein come up with the idea?

Consider, if you're in an F-16 travelling at 850 kph, relative to the ground, and launch a missile at 1,000 kph relative to you, your speed will be added to the missile's and it will go 1,850 relative to the ground. But if you're traveling in, say, a ship going at 0.9999999 c and fire a missile also at 0.99999 c, its top speed is 1 c and can't be more.

It turns out in all the histories of science I've read and all the science popularizations, none had bothered to mention a detail in Maxwell's equation, which describe the behavior of electromagnetic waves. It turns out Maxwell states these waves move at about 300,000 kilometers per second (or the speed of light), but from a stationary source.

Ah

Mystery solved.

Well, it is when you consider the Michaelson-Morley experiment.

Quote: Nareed

these waves move at about 300,000 kilometers per second (or the speed of light), but from a stationary source.

I thought the mystery came around when the speed of light proves to be the same speed when measured, no matter the source?

Quote:

the Michaelson-Morley experiment

yep, since space is not filled with ether, sooner or later that the ether theory was going to be busted

Quote: Evenbob

I'll bite, what do you know about the
universe you can't prove? If it's that god
created it, you don't know that, you're hoping
it and of course it can't be proved.

Planetary motions are predictable if you put the sun at the center of it all. You can then plot the orbits of planets vs the earth's motion to see how retrograde motions develop and work. Overtime, as observations became more keen, it was discovered that planet's orbits were elliptical, not circular. When you tied it in to Kepler;s law of planetary motion (which was an improvement over Copernicus) and Newton (calculus and gravitational force), you were pretty much able to figure it all out... none of which would be possible without Galileo's telescope and Tycho Brahe's observations.

Quote: odiousgambit

I thought the mystery came around when the speed of light proves to be the same speed when measured, no matter the source?

Nareed I think has me blocked, so ...

I'll just add, the one thing to really let sink in is that the concept of what is constant in our daily lives was shown to be all wrong by Relativity theory. We think time and space are constants as we go about our lives, but what is constant is the speed of light, which in order to be true has to alter time and space.

Quote: odiousgambit

Nareed I think has me blocked, so ...

Nareed has everybody blocked, he mostly talks
to himself. I tried to make it right with him but
he's having none of it.

Quote: boymimbo

When you tied it in to Kepler;s law of planetary motion (which was an improvement over Copernicus) and Newton (calculus and gravitational force), you were pretty much able to figure it all out... none of which would be possible without Galileo's telescope and Tycho Brahe's observations.

As a matter of fact, Kepler formulated his laws of planetary motions just before Galileo invented the telescope. Tycho, Kepler's mentor, was very likely the greatest, and last, overall naked-eye astronomer.

I wonder if I should add this to my "why did it take so long?" list. after all, a clever ancient astronomer, and there were many, could have figured it all out through observation. But cultural forces, a lack of scientific rigor and sophistication, and tellingly the prevalent beliefs of the times, likely made it impossible.

Quote: odiousgambit

Nareed I think has me blocked, so ...

You missed the whole point. There was no sense unraveling it.

Quote: Nareed

BTW, it's the little things.


It turns out in all the histories of science I've read and all the science popularizations, none had bothered to mention a detail in Maxwell's equation, which describe the behavior of electromagnetic waves. It turns out Maxwell states these waves move at about 300,000 kilometers per second (or the speed of light), but from a stationary source.

Maxwell's equation reminds me of my second year at the University of Iowa taking an astronomy/physics class. My professor, James Van Allen, was applying Maxwell's equations to the Van Allen radiation belts.

Development. If I understand this correctly, what has been spotted is electromagnetic radiation that does not fit with the expected profiles of known spectra - in other words, if the x-ray emissions were coming from carbon, it would be recognizable as such, but instead does not fit any known such.

http://www.theregister.co.uk/2014/12/13/dark_matter_photon_emission_epfl/