file formats
7 Jan 2008 16:25:25 UTC
Topic 193424
(moderation:
LS.
Is somewhere a description of the content of the files earth_... and sun_...? Which parameters are given and what units are used?
Similar questions for the other files in the directory ..../einstein.uwm.phys.edu
Dick.
file formats
)
Hmmm .... good question.
Quick answer: I think the Earth & Sun files are empherides - positional data - as I believe the calculations are referred back to the frame of the solar system's centre of mass.
But in case that's random rubbish from my head today, let me look into that and I'll get back on that .... :-)
Cheers, Mike.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
Yes, earth and sun are
)
Yes, earth and sun are ephemeris files, describing the motion of the sun and earth.
They are plain ASCII files. After the 1st header line there are 10 columns, giving the time (GPS seconds IIRC), 3 Cartesian cords for the position (in units of sec), 3 for velocity (sec/sec) and 3 for acceleration (1/sec). “sec� here means “light-sec� – light travel time from the Solar System Barycenter to the Earth or Sun, respectively.
The other files h1_* and l1_* contain pre-processed data from the detectors in a proprietary binary format, basically some frequency bins of the SFTs of several time stretches of detector data. H1 is data from Hanford, L1 from Livingston. The number in the filename is the base frequency of the data in the file, i.e. the frequency (in Hz) the lowest bins in a file correspond to.
BM
BM