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1

On some research, most likely what I saw was StarLink train 12. Maybe due to some clouds on that part of the sky, I was unable to see the entire train. Thanks. Also, I do not know if I am right, this is what I thought, when I read the launches page on this website.


9

The short answer: No The long answer: The Sun only has an analemma (the figure-8 shape traced on the sky as a result of imaging the Sun at the same time (good luck avoiding clouds) each day) because of two factors. The Earth is tilted on its axis and that axis remains pointed in the same direction in space (toward the direction of Polaris). (A more precise ...


10

Fortunately the free planetarium software Stellarium makes it easy to simulate this experiment. If you pause its clock and repeatedly press = to step forward 24 hours at a time, the stars appear to move westward about 1° per night as the Earth moves around the Sun. Stepping by 23h56m04s sidereal days with Alt = eliminates this effect. Unfortunately you can ...


4

As far as: Has anyone published an experiment where the same star is photographed every night at the same time? I don't know but if you did it would just be a dotted line across the sky. The stars cross the meridian about 4 minutes earlier at each night. If you photographed at local midnight and you saw a star low in the East and photographed every night ...


13

An analemma shows the position of the Sun in the sky from a fixed location on Earth at the same mean solar time. It gets its north-south shape because of the tilt of Earth's axis makes the declination of the sun change across the year, and the sideways shape due to the orbit nonuniformity. The star analemma would get a point at the same time every sidereal ...


9

The stars are very very far away. So far away that only the rotation of the Earth matters for their position in the sky. If you photograph a star every time the Earth completes a rotation, it will appear as a single point. But that's not what happens if you photograph it "at the same time". A day is slightly longer than one rotation of the Earth, ...


0

I have a photograph taken with an infrared camera (scattered blue light filtered out) from within a medieval tower open to the sky. The stars ARE visible.


7

Here's a screenshot from Stellarium (it's free and a fantastic tool for observers). I've set the location to Amsterdam and the time to 21:42 (local time) on the 15th of October. At this time Mars was just over 116° from north and 25° above the horizon. It's very bright at the moment. I was observing it a couple of nights ago and watched an airliner pass ...


7

Is the Object in this Photo Mars? Almost certainly yes if it didn't move like a plane or hover and make noise like a quadcopter. in-the-sky.org' skymap shows Mars at 117 degrees East and 25 degrees altitude at 21:43 local time in Woerden in central Netherlands yesterday. Clicking on Mars yields more information including a charts showing that it's close to ...


3

The Moon is visible only when it is above the horizon and not too near the Sun. Those times depend on its position in the sky relative to the Sun, and the lunar phase is related: 🌒 evening only 🌓 noon to midnight (90° east of Sun) 🌔 afternoon to early morning 🌕 sunset to sunrise (opposite Sun) 🌖 late evening to late morning 🌗 midnight to noon (90° west ...


5

Keep in mind that you have a 650mm telescope and Mars is small. While it is currently appearing larger because it is near opposition, it is still only 22 arc-seconds wide. Here's a simulated view of what you should see using a 650mm f/5 telescope with a 10mm Plössl type eyepiece (51° Apparent Field of View - chosen because Celestron offers that so I suspect ...


-1

Actually you only think the Moon appears to be perfect in your eyepiece. Take a good look at Lunar images made from above the atmosphere. Campbell gave you an very good explanation for what amounts to eyepiece viewing with any telescope is disappointing. This will of course get all the traditionalists up in arms but you have the ability to make up your own ...


5

Subject Size In angular dimensions, planets are tiny compared to the Moon. The Moon is roughly 30 arc-minutes (about 1/2° ... varying slightly from apogee to perigee). In real life they are, of course, MUCH larger than the Moon... but they are also MUCH farther away so they appear much smaller. In comparison to the Moon's approximately 30 arc-minutes size, ...


1

General guidance seems to be to use a magnification of 30 to 50 times the diameter in inches of your telescope's aperture. An aperture of 80mm is just over 3", so we are looking at magnifications of 90x to 150x. Your telescope has a focal length of 500mm without the Barlow lens, and 1500mm with the Barlow lens. Since magnification is simply the focal ...


5

This is an opinion based question and so I don't think there is an objective answer. For example what constitutes a wealthy person? However, in his book "Celestial Objects for Common Telescopes", first published in 1859, the author, Thomas Webb, writes: Instruments quite sufficient for the student's purpose are far less expensive than formerly; a ...


1

The first person to apply for a patent for a telescope was a Dutch eyeglass maker named Hans Lippershey (or Lipperhey). In 1608, Lippershey laid claim to a device that could magnify objects three times. However the word telescope is from Ancient Greek, so the concept is older than that. It wasn't until the 1930s, that due to the aluminized mirrors which were ...


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