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I am now running my annual July fund-raising campaign to celebrate the twelfth anniversary of the establishment of Behind the Black. For many reasons, mostly political but partly ethical, I do not use Google, Facebook, Twitter. These companies practice corrupt business policies, while targeting conservative websites for censoring, facts repeatedly confirmed by news stories and by my sense that Facebook has taken action to prevent my readers from recommending Behind the Black to their friends.


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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.

Conscious Choice cover

From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.

Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.  
Conscious Choice does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.


“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of founder of the Mars Society.


Available everywhere for $3.99 (before discount) at Amazon, Barnes & Noble, and all ebook vendors, or direct from the ebook publisher, ebookit. And if you buy it from ebookit you don't support the big tech companies and I get a bigger cut much sooner.


  • Ray Van Dune

    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.

  • Captain Emeritus

    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.

  • pzatchok

    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.

  • Kelly Ambrose (Sr.)

    Is mercury too heavy for a vacuum or too weird for a magnet to enable tipping?

  • pzatchok

    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.

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