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Top Document: [sci.astro] Time (Astronomy Frequently Asked Questions) (3/9) Previous Document: C.05 Was 2000 a leap year? Next Document: C.07 Easter: See reader questions & answers on this topic! - Help others by sharing your knowledge Paul Schlyter <pausch@saaf.se> There is a difference of opinion. Steve Willner writes: Big "end of millennium" parties were held on 1999-12-31. The psychological significance of changing the first digit in the year must not be discounted. (Preceeding these parties were the big headaches that occurred as everybody rushed to ensure---appropriately enough---that the date code in everybody's computer did not break on the next day.) However, the third millennium A.D. in fact begins on 2001-01-01; there was no year zero, and thus an interval of 2000 years from the arbitrary beginning of "A.D." dates will not have elapsed until then. More details may be found in an article by Ruth Freitag in the 1995 March newsletter of the American Astronomical Society. I am seeking permission to include the article in the FAQ. A view to the contrary is expressed by Paul Schlyter <pausch@saaf.se>: On 2000 January 1 of course! Some people argue that it should be 2001 January 1 just because Roman Numerals lacks a symbol for zero, but I find that irrelevant, because: 1. Our year count wasn't introduced until A.D. 525---thus the people who lived at A.D. 1 were completely unaware that we label that year "A.D. 1." 2. No real known event occurred at either 1 B.C. or A.D. 1---Jesus was born some 6--7 years earlier. Thus the new millennium should _really_ have been celebrated already, at least of we want to celebrate 2000 years since the event that supposedly started our way of counting years.... (Yes, the Julian calendar _was_ around at 1 B.C. and 1 A.D., but at that time the years was counted since the "foundation of Rome.") Interested readers may also want to check the Web sites of The Royal Observatory Greenwich <URL:http://www.rog.nmm.ac.uk/> and the US Naval Observatory <URL:http://www.usno.navy.mil/>. User Contributions:Comment about this article, ask questions, or add new information about this topic:Top Document: [sci.astro] Time (Astronomy Frequently Asked Questions) (3/9) Previous Document: C.05 Was 2000 a leap year? Next Document: C.07 Easter: Part0 - Part1 - Part2 - Part3 - Part4 - Part5 - Part6 - Part7 - Part8 - Single Page [ Usenet FAQs | Web FAQs | Documents | RFC Index ] Send corrections/additions to the FAQ Maintainer: jlazio@patriot.net
Last Update March 27 2014 @ 02:11 PM
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with stars, then every direction you looked would eventually end on
the surface of a star, and the whole sky would be as bright as the
surface of the Sun.
Why would anyone assume this? Certainly, we have directions where we look that are dark because something that does not emit light (is not a star) is between us and the light. A close example is in our own solar system. When we look at the Sun (a star) during a solar eclipse the Moon blocks the light. When we look at the inner planets of our solar system (Mercury and Venus) as they pass between us and the Sun, do we not get the same effect, i.e. in the direction of the planet we see no light from the Sun? Those planets simply look like dark spots on the Sun.
Olbers' paradox seems to assume that only stars exist in the universe, but what about the planets? Aren't there more planets than stars, thus more obstructions to light than sources of light?
What may be more interesting is why can we see certain stars seemingly continuously. Are there no planets or other obstructions between them and us? Or is the twinkle in stars just caused by the movement of obstructions across the path of light between the stars and us? I was always told the twinkle defines a star while the steady light reflected by our planets defines a planet. Is that because the planets of our solar system don't have the obstructions between Earth and them to cause a twinkle effect?
9-14-2024 KP