Category: GravityNotes

Comment on Earthquake Seismograph Using Bismuth Magnetic Levitator – about state of the art in low cost gravitational detector arrays

Earthquake seismograph using bismuth magnetic levitator as sensor at https://www.youtube.com/watch?v=aIANNzpec7Y Tomislav Stimac, The “standard” still for accelerometers is the small but global network of super conducting gravimeters (SGs). They use liquid helium cooled niobium magnetically levitated spheres as the test mass. The sensitivity is about 0.1 nanometers per second squared (nm/s2) at 1 sample per second.
Read More »

Comment on Video about laser interferometer design and use – replace superconducting gravimeters

Counting Atoms with the Doppler Effect – Heterodyne Interferometer by Sam Zeloof at http://sam.zeloof.xyz https://www.youtube.com/watch?v=vPu6lN9yJOY Sam, I sent you an email about using this to replace the network of superconducting gravimeters with something more people can afford. You have several orders of magnitude available to you by very small adjustments. SGs cost several hundred thousand and
Read More »

Plans for measuring the speed of gravity again, using superconducting gravimeter and related sensor networks

One linear regression is all that is needed to useg JPL Ephemeris to separate the sun moon from earth-based signals I want to repeat the SG network speed of gravity measurement I did in 2003 using all the current stations. I will also use the best of the broadband seismometers from IRIS.edu. Any absolute measurements,
Read More »

Some Notes on applications for MEMS gravimeters and their global calibration

Marley, For the last 20 years or so, I have been tracking gravimeter developments, hoping one day they could be developed enough to use in low cost gravitational imaging arrays. I don’t have my notes on what I wrote to you.  My memory is that I saw you were at “earth tide” sensitivity. That is
Read More »

Gravity and Temperature, gravity and pressure

Shawn, What I am saying is that the energy density of the radiation field of the earth, which you can map by mapping the temperature is just “gravitational field stuff”.  The magnetic field of the earth which you can convert to magnetic energy density is also made of “gravitational field stuff”. The gravitational field of
Read More »

Gravitational, Magnetic and Electric Field Changes from Global Climate Change

I wrote yesterday about magnetism and gravity and temperature at gravimeter and related sensor array detector sites.  I give averages over all frequencies, but the fine details can be tracked across all frequencies from picoHertz to ZettaHertz. Relation between gravity, magnetism and temperature at the earths surface at /?p=1893 Today I realized that if global
Read More »

Comment on Endaq Steve Hanly blog about accelerometer sensitivity

Accelerometer Specifications: Deciphering an Accelerometer’s Datasheet by Steve Hanly https://blog.endaq.com/accelerometer-specifications-decoding-a-datasheet I see you mention temperature sensitivity. I am writing an article on gravimeters and recommending different ones. Someone estimated their response to temperature. It can be estimated for gravimeter arrays. Here is how I estimated it. Relation between gravity, magnetism and temperature at the earths
Read More »

Why the sun moon tidal signal is so important for helping global sensor arrays with calibration

Shawn, I worked with the US Agency for International Development, the US State Department, World Bank and many international organizations.  Most countries cannot afford to do their own mineral exploration, so outsiders come and take what they have. I helped put microcomputer training and technology into that system so that some countries could afford to
Read More »

Relation between gravity, magnetism and temperature at the earths surface

I wrote this yesterday, and then realized that if global climate change increases the global temperature by 1 degree then that will change the readings at all accelerometer sites. But the (word that starts with i) at NASA and other places don’t give you the absolute temperature time series, only the change. But the impact
Read More »

Comment on my video Windows USB GPS Device Based on UBlox Chip and UCenter Software

Windows USB GPS Device Based on UBlox Chip and UCenter Software https://www.youtube.com/watch?v=uJZHVKGrl6Y @Ali Zitouna Hamed, I am not sure what you mean by “base ntrip”. I made this long ago and have not used UBlox lately. Since then i have been working on software defined radios, electromagnetic interference, gravitational wave detection, imaging arrays for gravitational
Read More »