1342: Ancient Stars - Revision history

172.71.134.217: /* Explanation */ Hey, me again. The 91 brighest stars list is now 93 stars long, so the numbers have slightly evolved.

2024-09-06T13:10:15Z

‎Explanation: Hey, me again. The 91 brighest stars list is now 93 stars long, so the numbers have slightly evolved.

172.71.135.47: /* Explanation */ The farthest star on the 91 brightest star list is not Aludra but Deneb, and is 2,600 ly away (Aludra is only 2,000 ly away by the way)

2024-09-06T13:08:07Z

‎Explanation: The farthest star on the 91 brightest star list is not Aludra but Deneb, and is 2,600 ly away (Aludra is only 2,000 ly away by the way)

172.70.91.72: /* Explanation */ Not a biblical name (that being an exception to the rule that I blame on the unformed literacy of early monk-scribes, and I don't even know why we should honour that principle), so much better to use the unvarnished version.

2024-09-01T09:49:21Z

‎Explanation: Not a biblical name (that being an exception to the rule that I blame on the unformed literacy of early monk-scribes, and I don't even know why we should honour that principle), so much better to use the unvarnished version.

172.70.160.137: /* Explanation */ Justify and generalise the enforced term-limit element. (And if anyone "does a Cleveland", it's still a distinct a discontinuitously different Administration you will land on; only for swathes of FDR's term could you claim 8.6yrs==same.)

2024-09-01T09:22:57Z

‎Explanation: Justify and generalise the enforced term-limit element. (And if anyone "does a Cleveland", it's still a distinct a discontinuitously different Administration you will land on; only for swathes of FDR's term could you claim 8.6yrs==same.)

172.70.160.231: /* Explanation */ Slightly disambiguate the "blink of an eye (in cosmic terms)", although of course with T=T0.root(1-v²/c²) one could argue that no eye need even bl8nk, if it is going that fast. And added "previous POTUS" exceptions, for certain times.

2024-09-01T09:09:00Z

‎Explanation: Slightly disambiguate the "blink of an eye (in cosmic terms)", although of course with T=T0.root(1-v²/c²) one could argue that no eye need even bl8nk, if it is going that fast. And added "previous POTUS" exceptions, for certain times.

172.70.231.66: Added a paragraph about the speed of light

2024-09-01T02:30:37Z

Added a paragraph about the speed of light

172.71.178.201: /* Explanation */

2023-09-16T15:33:36Z

‎Explanation

172.70.43.65: /* Explanation */

2023-09-16T15:05:25Z

‎Explanation

SilverTheTerribleMathematician: Hey.

2022-12-14T22:06:49Z

Hey.

Jacky720: rv

2022-05-04T21:02:14Z

Show changes

@@ Line 16: / Line 16: @@
 It's frequently cited that about 5,000 to 10,000 stars are visible in the sky by the naked eye. The {{W|Bright Star Catalogue}} is a star catalogue that lists all stars of {{W|apparent magnitude}} 6.5 or brighter, which is roughly every star visible to the naked eye from Earth. The catalog contains 9,110 objects, of which 9,096 are stars, ten are {{w|Nova|novae}} or {{w|supernovae}}, and four objects outside of our Milky Way (two {{w|globular cluster}}s and two {{w|open cluster}}s). To see most of these you need good eyes and a very dark night, and at any point you will only be able to see fewer than half of these as the rest are blocked by the Earth.
-This list shows the {{W|Visible stars|91 brightest stars}}. Of these 59 are more than 100 light years away and only 6 are more than 1,000 light years away. The farthest on this list, {{W|Deneb}}, is "only" 2,600 light years away. Our entire {{w|Milky Way}} contains up to 400 billion (400x10⁹) stars and has a diameter of 100,000 light years.
+This list shows the {{W|Visible stars|93 brightest stars}}. Of these 60 are more than 100 light years away and only 7 are more than 1,000 light years away. The farthest on this list, {{W|Deneb}}, is "only" 2,600 light years away. Our entire {{w|Milky Way}} contains up to 400 billion (400x10⁹) stars and has a diameter of 100,000 light years.
 There are visible objects much farther away, like the {{w|Andromeda Galaxy}} which is 2.5 million light years away and made up of billions of stars. And a gamma ray burst {{w|GRB 080319B}} would have been briefly visible to the naked eye, despite being 7.5 billion light years distant.

@@ Line 16: / Line 16: @@
 It's frequently cited that about 5,000 to 10,000 stars are visible in the sky by the naked eye. The {{W|Bright Star Catalogue}} is a star catalogue that lists all stars of {{W|apparent magnitude}} 6.5 or brighter, which is roughly every star visible to the naked eye from Earth. The catalog contains 9,110 objects, of which 9,096 are stars, ten are {{w|Nova|novae}} or {{w|supernovae}}, and four objects outside of our Milky Way (two {{w|globular cluster}}s and two {{w|open cluster}}s). To see most of these you need good eyes and a very dark night, and at any point you will only be able to see fewer than half of these as the rest are blocked by the Earth.
-This list shows the {{W|Visible stars|91 brightest stars}}. Of these 59 are more than 100 light years away and only 6 are more than 1,000 light years away. The farthest on this list, {{W|Eta Canis Majoris|Aludra}}, is "only" 3,200 light years away. Our entire {{w|Milky Way}} contains up to 400 billion (400x10⁹) stars and has a diameter of 100,000 light years.
+This list shows the {{W|Visible stars|91 brightest stars}}. Of these 59 are more than 100 light years away and only 6 are more than 1,000 light years away. The farthest on this list, {{W|Deneb}}, is "only" 2,600 light years away. Our entire {{w|Milky Way}} contains up to 400 billion (400x10⁹) stars and has a diameter of 100,000 light years.
 There are visible objects much farther away, like the {{w|Andromeda Galaxy}} which is 2.5 million light years away and made up of billions of stars. And a gamma ray burst {{w|GRB 080319B}} would have been briefly visible to the naked eye, despite being 7.5 billion light years distant.

@@ Line 12: / Line 12: @@
 The title text references the fact that most people have a hard time imagining the large scale of astronomical numbers. For example, the distance between astronomical bodies or the size of the Sun are hard to imagine; they typically underestimate them by many orders of magnitude and think they are much smaller than they actually are. See {{tvtropes|SciFiWritersHaveNoSenseOfScale|Sci-Fi Writers Have No Sense of Scale}}
-In this case, however, people instead overestimate both the number of visible stars and their distance by quite a bit. This could be a result of underestimating the speed of light, which is rather fast. Even though stars are incredibly far away (Sirius' 8.6ly translates to over 80 trillion kilometers), light is so fast that it can crosses those distances as fast as anything can (a relative blink in the eye, for the ''nearest'' of these vast distances). This underestimate of light results in an overestimate of the time it takes for light to reach us.
+In this case, however, people instead overestimate both the number of visible stars and their distance by quite a bit. This could be a result of underestimating the speed of light, which is rather fast. Even though stars are incredibly far away (Sirius's 8.6ly translates to over 80 trillion kilometers), light is so fast that it can crosses those distances as fast as anything can (a relative blink in the eye, for the ''nearest'' of these vast distances). This underestimate of light results in an overestimate of the time it takes for light to reach us.
 It's frequently cited that about 5,000 to 10,000 stars are visible in the sky by the naked eye. The {{W|Bright Star Catalogue}} is a star catalogue that lists all stars of {{W|apparent magnitude}} 6.5 or brighter, which is roughly every star visible to the naked eye from Earth. The catalog contains 9,110 objects, of which 9,096 are stars, ten are {{w|Nova|novae}} or {{w|supernovae}}, and four objects outside of our Milky Way (two {{w|globular cluster}}s and two {{w|open cluster}}s). To see most of these you need good eyes and a very dark night, and at any point you will only be able to see fewer than half of these as the rest are blocked by the Earth.

@@ Line 8: / Line 8: @@
 ==Explanation==
-[[Cueball]] makes the common observation that many of the visible stars in the sky are so distant that it takes thousands of years for light from that star to reach Earth. However, the brightest star {{W|Sirius}} is one of the nearest at a mere 8.6 {{W|Light-year|light-years}} distance. In other words, the light that was arriving from Sirius in March 2014, when the comic was posted, was emitted some time around August 2005. The previous US president, {{W|George W. Bush}}, was in office from 2001 to 2009 and [[Megan]] notes that this isn't a terribly impressive observation. At certain times (mostly when the previous US president served only a single term, but also for a short time after the inauguration of a new president), looking to events of 8.6 years ago would stretch ''beyond'' just the prior administration, but even two ({{w|Ronald Reagan|rarely}} being {{w|Richard Nixon|three}}, or {{w|Grover Cleveland#First presidency (1885–1889)|possibly}} even {{w|Ulysses S. Grant|more}}) predecessors ago would not be considered impressive in the circumstances.
+[[Cueball]] makes the common observation that many of the visible stars in the sky are so distant that it takes thousands of years for light from that star to reach Earth. However, the brightest star {{W|Sirius}} is one of the nearest at a mere 8.6 {{W|Light-year|light-years}} distance. In other words, the light that was arriving from Sirius in March 2014, when the comic was posted, was emitted some time around August 2005. The previous US president, {{W|George W. Bush}}, was in office from 2001 to 2009 and [[Megan]] notes that this isn't a terribly impressive observation. At certain times (mostly when the previous US president served only a single term, but also {{w|Twenty-second Amendment to the United States Constitution|currently}} for a short time after the inauguration of any incoming president), looking to events of 8.6 years ago would stretch ''beyond'' just the prior administration, but even two ({{w|Ronald Reagan|rarely}} being {{w|Richard Nixon|three}}, or {{w|Grover Cleveland#First presidency (1885–1889)|possibly}} even {{w|Ulysses S. Grant|more}}) predecessors ago would not be considered impressive in the circumstances.
 The title text references the fact that most people have a hard time imagining the large scale of astronomical numbers. For example, the distance between astronomical bodies or the size of the Sun are hard to imagine; they typically underestimate them by many orders of magnitude and think they are much smaller than they actually are. See {{tvtropes|SciFiWritersHaveNoSenseOfScale|Sci-Fi Writers Have No Sense of Scale}}

@@ Line 8: / Line 8: @@
 ==Explanation==
-[[Cueball]] makes the common observation that many of the visible stars in the sky are so distant that it takes thousands of years for light from that star to reach Earth. However, the brightest star {{W|Sirius}} is one of the nearest at a mere 8.6 {{W|Light-year|light-years}} distance. In other words, the light that was arriving from Sirius in March 2014, when the comic was posted, was emitted some time around August 2005. The previous US president, {{W|George W. Bush}}, was in office from 2001 to 2009 and [[Megan]] notes that this isn't a terribly impressive observation.
+[[Cueball]] makes the common observation that many of the visible stars in the sky are so distant that it takes thousands of years for light from that star to reach Earth. However, the brightest star {{W|Sirius}} is one of the nearest at a mere 8.6 {{W|Light-year|light-years}} distance. In other words, the light that was arriving from Sirius in March 2014, when the comic was posted, was emitted some time around August 2005. The previous US president, {{W|George W. Bush}}, was in office from 2001 to 2009 and [[Megan]] notes that this isn't a terribly impressive observation. At certain times (mostly when the previous US president served only a single term, but also for a short time after the inauguration of a new president), looking to events of 8.6 years ago would stretch ''beyond'' just the prior administration, but even two ({{w|Ronald Reagan|rarely}} being {{w|Richard Nixon|three}}, or {{w|Grover Cleveland#First presidency (1885–1889)|possibly}} even {{w|Ulysses S. Grant|more}}) predecessors ago would not be considered impressive in the circumstances.
 The title text references the fact that most people have a hard time imagining the large scale of astronomical numbers. For example, the distance between astronomical bodies or the size of the Sun are hard to imagine; they typically underestimate them by many orders of magnitude and think they are much smaller than they actually are. See {{tvtropes|SciFiWritersHaveNoSenseOfScale|Sci-Fi Writers Have No Sense of Scale}}
-In this case, however, people instead overestimate both the number of visible stars and their distance by quite a bit. This could be a result of underestimating the speed of light, which is rather fast. Even though stars are incredibly far away (Sirius' 8.6ly translates to over 80 trillion kilometers), light is so fast that it can cross those distances in the blink of an eye (on a space timescale). This underestimate of light results in an overestimate of the time it takes for light to reach us.
+In this case, however, people instead overestimate both the number of visible stars and their distance by quite a bit. This could be a result of underestimating the speed of light, which is rather fast. Even though stars are incredibly far away (Sirius' 8.6ly translates to over 80 trillion kilometers), light is so fast that it can crosses those distances as fast as anything can (a relative blink in the eye, for the ''nearest'' of these vast distances). This underestimate of light results in an overestimate of the time it takes for light to reach us.
 It's frequently cited that about 5,000 to 10,000 stars are visible in the sky by the naked eye. The {{W|Bright Star Catalogue}} is a star catalogue that lists all stars of {{W|apparent magnitude}} 6.5 or brighter, which is roughly every star visible to the naked eye from Earth. The catalog contains 9,110 objects, of which 9,096 are stars, ten are {{w|Nova|novae}} or {{w|supernovae}}, and four objects outside of our Milky Way (two {{w|globular cluster}}s and two {{w|open cluster}}s). To see most of these you need good eyes and a very dark night, and at any point you will only be able to see fewer than half of these as the rest are blocked by the Earth.

@@ Line 18: / Line 18: @@
 There are visible objects much farther away, like the {{w|Andromeda Galaxy}} which is 2.5 million light years away and made up of billions of stars. And a gamma ray burst {{w|GRB 080319B}} would have been briefly visible to the naked eye, despite being 7.5 billion light years distant.
-See also [[1212: Interstellar Memes]], [[1644: Stargazing]], and [[1440:_Geese]].
+See also [[1212: Interstellar Memes]], [[1644: Stargazing]] and [[1440: Geese]].
 ==Transcript==

@@ Line 10: / Line 10: @@
 [[Cueball]] makes the common observation that many of the visible stars in the sky are so distant that it takes thousands of years for light from that star to reach Earth. However, the brightest star {{W|Sirius}} is one of the nearest at a mere 8.6 {{W|Light-year|light-years}} distance. In other words, the light that was arriving from Sirius in March 2014, when the comic was posted, was emitted some time around August 2005. The previous US president, {{W|George W. Bush}}, was in office from 2001 to 2009 and [[Megan]] notes that this isn't a terribly impressive observation.
-The title text references the fact that most normal people have a hard time imagining the large scale of astronomical numbers. For example, the distance between astronomical bodies or the size of the Sun are hard to imagine; they typically underestimate them by many orders of magnitude and think they are much smaller than they actually are. See {{tvtropes|SciFiWritersHaveNoSenseOfScale|Sci-Fi Writers Have No Sense of Scale}}
+The title text references the fact that most people have a hard time imagining the large scale of astronomical numbers. For example, the distance between astronomical bodies or the size of the Sun are hard to imagine; they typically underestimate them by many orders of magnitude and think they are much smaller than they actually are. See {{tvtropes|SciFiWritersHaveNoSenseOfScale|Sci-Fi Writers Have No Sense of Scale}}
 In this case, however, people instead overestimate both the number of visible stars and their distance by quite a bit. It's frequently cited that about 5,000 to 10,000 stars are visible in the sky by the naked eye. The {{W|Bright Star Catalogue}} is a star catalogue that lists all stars of {{W|apparent magnitude}} 6.5 or brighter, which is roughly every star visible to the naked eye from Earth. The catalog contains 9,110 objects, of which 9,096 are stars, ten are {{w|Nova|novae}} or {{w|supernovae}}, and four objects outside of our Milky Way (two {{w|globular cluster}}s and two {{w|open cluster}}s). To see most of these you need good eyes and a very dark night, and at any point you will only be able to see fewer than half of these as the rest are blocked by the Earth.