Hulleye Comes By!

Paul Hickson in American Scientist:

For almost a century, astronomers have experimented with the intriguing idea of building telescope mirrors out of mercury. The reason is that it is relatively easy to get a liquid to take on the required parabolic profile—all one needs to do is to place it on a spinning platter—whereas solid mirrors require meticulously grinding the shape from glass. The obvious shortcoming of liquid-mirror telescopes is that they can only point straight up. Fortunately, for many studies this is the best direction to look, because the line of sight passes through the least amount of atmosphere. What’s more, the practice of “drift scanning” with modern CCD detectors circumvents the inability of liquid-mirror telescopes to track a target as it moves across the sky. The author reports the progress his group has made constructing a 6-meter liquid-mirror telescope, and he discusses plans for other instruments of this kind to be built at more suitable sites—perhaps even on the Moon.

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The dish is made of lightweight foam sandwiched between skins of fiber-reinforced plastic. The trusses (b) are affixed to the dish using hinged mounts that can accommodate different degrees of thermal expansion in the materials used above and below.

The number of children under the age of 17 shot by guns in America every year is greater than the gun-related deaths of children in all the industrialized nations of the world COMBINED.

Here is the population of Japan: 127,463,611.

Here is the number of children killed by guns in Japan every year: 0.

A 2001 Centers for Disease Control (CDC) study found that in homicides among intimate partners, women are murdered more with guns than with all other means COMBINED.

In 2004, guns were most commonly used by males to murder their female partners.

A 2003 study found women living with a gun in the home were almost three times more likely to be murdered than women with no gun in the home.

“If we ban handguns only criminals will have guns.” Well then let’s not have any laws in America at all. No drug laws, no traffic laws, no laws at all, right? Duh.

“Cars kill people!!” Yes, cars kill people when something goes wrong. Guns are MADE to kill people…

More here.