A telescope using a liquid mirror about to become operational
Link here. The telescope, located in the Himalayas, is “an international collaboration between institutions in India, Belgium, Poland, Uzbekistan and Canada.”
The mirror works by rotating it so that its thin layer of liquid mercury forms a parabola.
The tradeoff is that the [telescope]is fixed in a single position, so it only observes one strip of the night sky as the Earth rotates below it. But since the telescope will be hyper-focused on just one area, it’s well-suited for spotting transient objects like supernovas and asteroids.
It appears the scientists will use it to study this same strip of sky over five years, hoping to detect changes in that time period.
This telescope is more a technology test than an actual observatory. Eventually the best place to put such a telescope — and much larger — will be on the Moon, and to do that requires some construction and testing beforehand.
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In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
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Link here. The telescope, located in the Himalayas, is “an international collaboration between institutions in India, Belgium, Poland, Uzbekistan and Canada.”
The mirror works by rotating it so that its thin layer of liquid mercury forms a parabola.
The tradeoff is that the [telescope]is fixed in a single position, so it only observes one strip of the night sky as the Earth rotates below it. But since the telescope will be hyper-focused on just one area, it’s well-suited for spotting transient objects like supernovas and asteroids.
It appears the scientists will use it to study this same strip of sky over five years, hoping to detect changes in that time period.
This telescope is more a technology test than an actual observatory. Eventually the best place to put such a telescope — and much larger — will be on the Moon, and to do that requires some construction and testing beforehand.
Readers!
Please consider supporting my work here at Behind the Black. Your support allows me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Only now does it appear that Washington might finally recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation or subscription:
4. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.
Canada has been a pioneer in rotating mercury mirror technology – I recall reading about an experimental observatory using a rotating mercury mirror in southern British Columbia 20 years ago. They were pretty cagey about where it was located, since it was on park land and they were afraid of vandalism or other kinds of disturbance. IIRC at that observatory they experimented with a flat mirror to allow the scope to scan to a degree. But of course, that was an alt-azimuth scan since the mirror could not be tilted, which would rotate the image. In addition, every reflection reduces the light transmitted by some percent, so there was speculation that future such telescopes would forgo such a scanning mirror.
I made liquid lens for years to pass vision acuity tests for the Feds.
Just yank a few hairs from a nostril, cause a tear to form, and squint…
you can read the bottom line without correction.
Some one tried making a mirror out of Mylar.
This was first tried in 1908. H. C. King, The History of the Telescope. A very interesting book for all telescope fans.
Is mercury too heavy for a vacuum or too weird for a magnet to enable tipping?
In a vacuum the mercury would be fine.
In zero G it would be spun to the edge of its tray or container, It needs the gravity to pull it back down to the center to form a dish shape.
If it tilted in gravity the gravity would pull it down to the lower edge thus distorting the shape.