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Any amateur astronomers here?


Prophet Zacharia

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Venus and Jupiter are close together in the night sky after sunset now and that's what the camera that took your picture captured - Venus being the brighter planet due to being much, much closer to us than Jupiter and having a much lighter cloud layer.  Venus and Mercury are sometimes called the "morning and evening stars" because they are between us and the Sun, so they can't appear high in the Earth's sky when it's dark.  So, when Jupiter is close to Venus, that means its actually on the opposite side of the Sun from the Earth, otherwise it couldn't appear closer to the Sun than the Earth as Venus is.

I taught astronomy and I've also made my own Newtonian Telescopes, up to 12.5" in diameter, grinding, polishing, and figuring the mirrors to less than 2 millionths of an inch of a perfect parabola. With the 12.5" one, which I built a Dobsonian mount to hold, I can even see dust storms on Mars (looking at the edge of the planetary disc) and Galaxies that are very far away, even in light polluted areas like the Baltimore suburbs.

I know the night sky well enough to find many of the Messier Objects (exploded stars, dust clouds, star clusters) by jumping along or between certain stars.

Unfortunately, I haven't had a lot of time for astronomy lately.  I have a 16" double-annealed Pyrex blank and would like to grind/polish/figure that to a parabola and have an aluminum mirror coating placed on it with a 4.5 focal length so the light travels from mirror 16" x 4.5 = 72" - about 10" of which is sideways and the rest along the telescope tube, so that I can look through the eyepiece standing on the ground for most things or on a small, 2' x 2'x 1' step stool I'll make.  The 16" mirror would capture 16^2/12.5^2 = 1.64 times as much light and would make very distant galaxys and nebulas brighter and would allow higher magnification by stronger eyepieces of the surface of Mars and Jupiter, as well as the Moon, but it would make the Moon so bright in the eyepiece a polarizing lens would be needed to make it darker - the same way the night mirror on a car works.

It's on my bucket list.

Here's an online recent picture I found of Jupiter and Venus. Venus is the brighter planet:

image.thumb.png.4814b3cea8210fe8176c0efe3c84eba0.png

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