Quicksilver: Liquid Mercury Thoughts

Why would a liquid mercury mirror telescope become the focus of several alphabet agencies and cause the shutdown of a small town?

First off, just what IS a liquid mirror telescope???

A liquid mirror telescope in this design, has the optical sensors mounted above the mirror, in a module at its focus, and the motor and bearings that turn the mirror are in the same module as the sensors. The mirror is suspended below.

Liquid mirror telescopes are telescopes with mirrors made with a reflective liquid. The most common liquid used is mercury, but other liquids will work as well (for example, low melting alloys of gallium). The liquid and its container are rotated at a constant speed around a vertical axis, which causes the surface of the liquid to assume a paraboloidal shape, suitable for use as the primary mirror of a reflecting telescope. The rotating liquid assumes the paraboloidal shape regardless of the container’s shape. To reduce the amount of liquid metal needed, and thus weight, a rotating mercury mirror uses a container that is as close to the necessary parabolic shape as possible. Liquid mirrors can be a low cost alternative to conventional large telescopes. Compared to a solid glass mirror that must be cast, ground, and polished, a rotating liquid metal mirror is much less expensive to manufacture.

From <https://en.wikipedia.org/wiki/Liquid_mirror_telescope>

However, there are much safer and easier and CHEAPER ways to do a liquid mirror and they were known about so long ago that the pages I found were archived.


These pages were archived:

May 4, 2006, 9:21 am

From <https://web.archive.org/web/20060504132201/http:/wood.phy.ulaval.ca:80/index.php>

A far better solution to mercury are ferrofluids with nano particles of iron suspended in a viscous fluid with a layer of silver nano particle on top that utilize magnetic control while being far less dangerous to the operators and the environment.

In previous attempts to deform liquid mirrors, the goal was generally to modify the shape of the mirror as a whole and not make the kind of rapidly changing wave front corrections needed for adaptive optics. These attempts focused on mercury, as was used in the first generation of LMTs at Laval.

The problem with using mercury as a DM is that because of its high density, a substantial force is needed to deform it. Our solution is to use an oil-based magnetic liquid called a ferrofluid which can be easily shaped in a magnetic field. Pure ferrofluids have very low reflectivity, a problem that is solved be coating them with a reflective layer called a MELLF which provides excellent reflectivity while adjusting to the shape of the ferrofluid underneath.

From <https://web.archive.org/web/20060107082208/http://wood.phy.ulaval.ca:80/ferrofluids/dm.php>


Testing liquid deformable mirrors

Small flat mirrors are very well suited to interferometric testing. In this technique, an instrument emits a laser beam which reflects off the test surface and is compared to a reference beam inside the interferometer. Any deviations from a perfectly flat surface cause a difference in the optical path between the test and reference beams, resulting in a pattern of interference fringes that is captured by a CCD camera. These fringes can then be analyzed by computer to show the heights of surface features with a precision on the order of 1/20th of a wave or better. Most interferometers take several images to reconstruct a surface and thus are unable to measure quickly changing features as is the case with these deformable mirrors. To get around this problem we made measurements using an innovative interferometer design called the PhaseCam from 4D Technology. By employing a technique called modal analysis we were able to obtain animated measurements using this equipment and also delineate the dynamic characteristics of several different magnetic liquids.


Figures of merit.

When we talk about the properties of a deformable mirror, there are several key parameters we are interested in.

Influence function:

This is the shape of the surface when deformed by a single actuator.





Response time:

this is a measure of how fast the mirror can be driven, a critical factor in astronomical imaging as the mirror must be able to keep pace with changes due to atmospheric turbulence.


This is the maximum deflection of the deformable mirror surface. This in turn determines the size of the largest aberrations that can be compensated for (due to the atmosphere or other elements in the optical system)

From <https://web.archive.org/web/20060505092147/http://wood.phy.ulaval.ca:80/ferrofluids/testing.php>


I bring all this to your attention because of what we know about interferometry and spinning mercury vortexes and the ability to send frequency wave lengths through a viscous material like mercury.

What we are seeing when we look at the world are interference patterns between matter and spirit that have aggregated mass – physicality. There is a science to this and it is called interferometry.

Interferometry is a family of techniques in which waves, usually electromagnetic waves, are superimposed causing the phenomenon of interference in order to extract information.[1] Interferometry is an important investigative technique in the fields of astronomy, fiber optics, engineering metrology, optical metrology, oceanography, seismology, spectroscopy (and its applications to chemistry), quantum mechanics, nuclear and particle physics, plasma physics, remote sensing, biomolecular interactions, surface profiling, microfluidics, mechanical stress/strain measurement, velocimetry, and optometry.[2]:1–2

These patterns equate to what could be called a template. This template can be measured for every manifested thing from rocks and dirt through all life forms up and to weather and energy.

So: affect the lattice – affect us or vice versa, affect the us – affect the lattice.

The ability to weaponize a spinning mercury mirror of the size needed for an astronomical observatory is foolishly easy. If you know the lattice pattern of anything (the frequency) you simply tune the bowl of mercury to that frequency, aim it and send a pulsed frequency that is out of phase at your target and whammo! (IMO)

Interference (wave propagation)

Interferometry makes use of the principle of superposition to combine waves in a way that will cause the result of their combination to have some meaningful property that is diagnostic of the original state of the waves. This works because when two waves with the same frequency combine, the resulting intensity pattern is determined by the phase difference between the two waves—waves that are in phase will undergo constructive interference while waves that are out of phase will undergo destructive interference. Waves which are not completely in phase nor completely out of phase will have an intermediate intensity pattern, which can be used to determine their relative phase difference. Most interferometers use light or some other form of electromagnetic wave.[2]

From <https://en.wikipedia.org/wiki/Interferometry>

IMO this might have also been an option as to why the place is now under alphabet control – especially if you could remotely operate the telescope – which, if it was a mercury mirror you would have to remotely operate it to protect your personnel.


Just a quick(silver) thought…



Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s