Marathoner Posted April 3 Group: Royal Member Followers: 16 Topic Count: 71 Topics Per Day: 0.05 Content Count: 10,200 Content Per Day: 7.07 Reputation: 13,193 Days Won: 99 Joined: 05/24/2020 Status: Online Share Posted April 3 Distance matters. Why doesn't the Sun fill the entire sky? The diameter of the Sun is a little over 865,000 miles in diameter after all. Answer? The Sun is over 93,000,000 miles from the Earth. An object of that size, distance, and relative luminosity would appear exactly the way that it does in the sky. Okay, so then why doesn't Mercury or Venus cast a shadow upon the earth whenever they eclipse the Sun? Answer: they do, in fact, cast a shadow whenever their respective orbits place them between Earth and the Sun. However, the distance and relative size of both render the umbra so ifintesmially small that it can only be witnessed via astronomical viewing devices. We don't see it here on Earth. 1 Link to comment Share on other sites More sharing options...
other one Posted April 3 Group: Worthy Ministers Followers: 29 Topic Count: 598 Topics Per Day: 0.08 Content Count: 56,181 Content Per Day: 7.56 Reputation: 27,907 Days Won: 271 Joined: 12/29/2003 Status: Offline Share Posted April 3 13 minutes ago, Jedi4Yahweh said: If you are standing in the shadow of the plane then the sun is being blocked entirely by the plane. If you are standing outside the shadow of the plane then no the sun is not being entirely blocked. In the same way someone in Texas is in the shadow of the eclipse, but someone in Arizona at that same time can see the Sun. How far is the plane away from you? Link to comment Share on other sites More sharing options...
tim_from_pa Posted April 3 Group: Advanced Member Followers: 3 Topic Count: 12 Topics Per Day: 0.01 Content Count: 449 Content Per Day: 0.48 Reputation: 302 Days Won: 0 Joined: 10/13/2021 Status: Offline Share Posted April 3 22 hours ago, Jedi4Yahweh said: How can the shadow of the moon be so much smaller than the moon itself? When you put an object in front of a light source the umbra (darker inner shadow) is always far bigger than the actual object. Show me a real world experiment where the umbra (inner shadow) is smaller than the actually object being projected. Before you go on about penumbra, I know that every shadow has a penumbra which is a outer thin hazy shadow where the shadow is diffusing with the surrounding light, but when they use it to explain the solar eclipses the penumbra is not a thin layer but a massively thicker layer that far exceeds the thickness of the actual shadow of the moon is projecting. This does not happen in real world experiments. Try it and see. It's all in the geometry. The umbra of the shadow is the region where the moon totally covers the sun. The penumbra is only a partly covered sun (and would appear to be, for example, a crescent sun). The moon's umbra only extends so far out into space so that as one gets further from the moon in front of the sun, the umbra at some point is non-existent, I.e., the moon can no longer cover all of the sun, so it's only a partial blockage of the sun (when a plant like Mercury goes across the sun, we can see a little black dot and it's called a transit). When we are close to the moon, the shadow is so much bigger approaching the diameter of the moon. The Earth lies between the two extremes and thus the shadow is smaller than the moon, but there is still an area where the sun is totally covered. See the attached picture. Link to comment Share on other sites More sharing options...
Jedi4Yahweh Posted April 3 Group: Diamond Member Followers: 2 Topic Count: 75 Topics Per Day: 0.01 Content Count: 1,955 Content Per Day: 0.26 Reputation: 636 Days Won: 1 Joined: 11/12/2003 Status: Offline Author Share Posted April 3 (edited) 48 minutes ago, Marathoner said: Distance matters. Why doesn't the Sun fill the entire sky? The diameter of the Sun is a little over 865,000 miles in diameter after all. Answer? The Sun is over 93,000,000 miles from the Earth. An object of that size, distance, and relative luminosity would appear exactly the way that it does in the sky. Okay, so then why doesn't Mercury or Venus cast a shadow upon the earth whenever they eclipse the Sun? Answer: they do, in fact, cast a shadow whenever their respective orbits place them between Earth and the Sun. However, the distance and relative size of both render the umbra so ifintesmially small that it can only be witnessed via astronomical viewing devices. We don't see it here on Earth. You can recreate this on a smaller scale and it will never create a shadow that is smaller than the object being projected. Put a flash light 93 inches away from a surface then but a smaller object 1/4" a way and see if it creates a smaller shadow than the actual object or not. Projected shadows are never smaller. Edited April 3 by Jedi4Yahweh 1 Link to comment Share on other sites More sharing options...
other one Posted April 3 Group: Worthy Ministers Followers: 29 Topic Count: 598 Topics Per Day: 0.08 Content Count: 56,181 Content Per Day: 7.56 Reputation: 27,907 Days Won: 271 Joined: 12/29/2003 Status: Offline Share Posted April 3 4 minutes ago, Jedi4Yahweh said: You can recreate this on smaller scale and it will never create a shadow that is smaller the the object being projected. Put a flash light 93 inches away form a surface then but a smaller object 1/4" a way and see if it creates a small shadow than the actual object or not. Projected shadows are never smaller. The flashlight is an almost single point of light source, unlike the sun, which is so large that the light comes from different point sources across it's face. I don't have the time to draw it out tonight, but the difference you are seeing is from the source light not being huge and giving off light in all directions.. Link to comment Share on other sites More sharing options...
Jedi4Yahweh Posted April 3 Group: Diamond Member Followers: 2 Topic Count: 75 Topics Per Day: 0.01 Content Count: 1,955 Content Per Day: 0.26 Reputation: 636 Days Won: 1 Joined: 11/12/2003 Status: Offline Author Share Posted April 3 2 minutes ago, other one said: The flashlight is an almost single point of light source, unlike the sun, which is so large that the light comes from different point sources across it's face. I don't have the time to draw it out tonight, but the difference you are seeing is from the source light not being huge and giving off light in all directions.. Well get you a bigger light and you will still get the same results. Link to comment Share on other sites More sharing options...
other one Posted April 3 Group: Worthy Ministers Followers: 29 Topic Count: 598 Topics Per Day: 0.08 Content Count: 56,181 Content Per Day: 7.56 Reputation: 27,907 Days Won: 271 Joined: 12/29/2003 Status: Offline Share Posted April 3 1 minute ago, Jedi4Yahweh said: Well get you a bigger light and you will still get the same results. I don't get those results from the light in my ceiling. It comes from a larger surface Link to comment Share on other sites More sharing options...
Jedi4Yahweh Posted April 3 Group: Diamond Member Followers: 2 Topic Count: 75 Topics Per Day: 0.01 Content Count: 1,955 Content Per Day: 0.26 Reputation: 636 Days Won: 1 Joined: 11/12/2003 Status: Offline Author Share Posted April 3 1 minute ago, other one said: I don't get those results from the light in my ceiling. It comes from a larger surface Probably not bright enough to project. Link to comment Share on other sites More sharing options...
other one Posted April 3 Group: Worthy Ministers Followers: 29 Topic Count: 598 Topics Per Day: 0.08 Content Count: 56,181 Content Per Day: 7.56 Reputation: 27,907 Days Won: 271 Joined: 12/29/2003 Status: Offline Share Posted April 3 1 minute ago, Jedi4Yahweh said: Probably not bright enough to project. No, unlike the sun, is not coming from a single point of light. Link to comment Share on other sites More sharing options...
Jedi4Yahweh Posted April 3 Group: Diamond Member Followers: 2 Topic Count: 75 Topics Per Day: 0.01 Content Count: 1,955 Content Per Day: 0.26 Reputation: 636 Days Won: 1 Joined: 11/12/2003 Status: Offline Author Share Posted April 3 1 minute ago, other one said: No, unlike the sun, is not coming from a single point of light. Well the sun is a single source. Link to comment Share on other sites More sharing options...
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