A telescope using a liquid mirror about to become operationalLink 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.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
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.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
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.