Recent content by mattrix

Thank you, every one. @Baluncore. I had already accepted your point. My comment was about the "steady" effect of the moon, given that it is constantly changing position. However, you seem to suggest that the spin of the earth cycles between established limits, an interglacial rate, and a...

I know old thread. @phinds, "What if" questions are par for the course. Physics principles are taught in isolation, with an unstated "given all other things". The student is left to extrapolate for themselves. I have a question of my own that violates the laws, and I am not sure how to ask it...

Thankyou, though I don't think its as steady as you suggest. Your answer does raise a few other questions, but I will refrain from giving any elaboration if I ask them.

I see. The ideas came from a range of places and have been floating around in my head for a while. They came from things I've read, not necessarily equally reliable. Most papers are behind paywalls, so I only have abstracts and reports by people who supposedly have read the papers. Things I've...

Sorry that my wording upset you. The propositions can't all be correct, can they? I take the lack of response to the content of the question to indicate that none of the propositions show any merit.

Ignoring global warming, the Earth will spin progressively slower. But how will global warming affect this? THEY say, LESS water, LESS slowing. > slowing spin is all about the FRICTION from the action of WATER on the LAND, when the water is gone the slowing of the spin will ceased (or at least...

Thanks berkeman, A lot of information in that link. I will have to read it a few times to get all this to gel. In my case, I am presented with data that has already been sampled for digital storage. I do know that it has been oversampled/decimated so I guess some care has been taken with the data.

No explicit filtering has been applied. So I guess bandwidth is infinite? I'm intending to use FFTW to explore the data. And treating this as a math problem (maybe incorrectly?) IIRC the number of samples I choose to use determines the longest period I can detect in the data. In the proposed...

So does what I intend to do: Sample the data for 'm' periods: do an FFTW: select suitable components: convert them back to a continuous time waveform. seem reasonable? Does it pose any problems or introduce significant artifacts?

Thank you DrClaude, That does what I intended well. Though it has sent me down a rabbit hole of new searches.

Thankyou everyone, I knew there was more to this question than I could recall. The trouble with University math is that all the functions are easily describable in the time domain, and hence manipulable. Real data doesn't obey these rules. I am assuming that the real data has, 1. high frequency...

It has been 35 years since I did the math for Fourier analysis, and I have forgotten what the subtleties are. Please be kind. So this is not a how do I calculate a DFT (though that may be my next question) but rather how do I use it, and interpret the results. All the online and software I find...

Hi Tony, thanks for the link. Thats my point, these data are for the exact same moment as when the J2000 plane is defined, and they are both "mean" values. So if there is an inclination at this time, what is the plane its inclined to? Interesting graph, if your guesses are right...

Can someone please help me with this? Epoch J2000.0 refers coordinate systems to the mean equinox and mean ecliptic of January 1, 2000, noon TT. I have the following mean orbital elements for Earth with element date January 1, 2000 and referred to j2000.0 epoch. a :=...