2622: Angular Diameter Turnaround - Revision history

2601:541:B80:2CCB:AD4C:5BCD:BCFA:371D: Fix link to angular diameter distance broken in last edit

2025-12-10T22:52:29Z

Fix link to angular diameter distance broken in last edit

2.98.65.8: /* Explanation */ More optimal recapitalisation (and plural-handling, etc).

2025-10-24T18:08:19Z

‎Explanation: More optimal recapitalisation (and plural-handling, etc).

162.218.182.3: /* Explanation */ Capitalization

2025-10-24T16:16:08Z

‎Explanation: Capitalization

162.158.155.89: /* Transcript */

2023-07-28T01:13:09Z

‎Transcript

Firestar233: grammar

2023-06-19T00:51:53Z

grammar

Jkshapiro: /* Explanation */ removed unsupported references to "hell"

2023-06-06T02:01:53Z

‎Explanation: removed unsupported references to "hell"

Xurkitree10: /* Transcript */

2023-04-22T13:04:05Z

‎Transcript

Natg19: /* Transcript */ cosmology

2023-01-11T23:32:15Z

‎Transcript: cosmology

172.70.218.41: /* Explanation */

2022-11-01T16:48:44Z

‎Explanation

172.70.114.215: /* Explanation */ don't be so rude

2022-08-23T20:23:22Z

‎Explanation: don't be so rude

@@ Line 8: / Line 8: @@
 ==Explanation==
-This comic references multiple physics and maths concepts, including {{w|angular diameter}}, {{w|angular diameter distance}, {{w|redshift}}, and {{w|mobile phone}}s, although mobile phones are not a core science at this time.{{Citation needed}}
+This comic references multiple physics and maths concepts, including {{w|angular diameter}}, {{w|angular diameter distance}}, {{w|redshift}}, and {{w|mobile phone}}s, although mobile phones are not a core science at this time.{{Citation needed}}
 The comic shows the galaxies of the universe as Samsung Galaxy mobile phones, pairing the age we see them at from earth, the degree they are redshifted, and how much of the sky they take up, known as their angular diameter. The mobile phones that are closer and older have depleted batteries, whereas the batteries are full for those phones from which the light is still only beginning to reach us. This is how galaxies appear in the sky if they were phones that had batteries lasting billions of years, the light reaching us from deeper into the past as it comes from objects that are farther away. Phones at a low battery may be a reference to [[1373: Screenshot]], where Randall commented that it is hard to pay attention to any phone with a low battery as the need to charge it is so urgent.

@@ Line 8: / Line 8: @@
 ==Explanation==
-This comic references multiple physics and maths concepts, including {{w|Angular diameter|angular diameter}}, {{w|Angular diameter distance|angular diameter distance}}, {{w|Redshift|redshift}}, and {{w|phones|mobile phones}}, although mobile phones are not a core science at this time.{{Citation needed}}
+This comic references multiple physics and maths concepts, including {{w|angular diameter}}, {{w|angular diameter distance}, {{w|redshift}}, and {{w|mobile phone}}s, although mobile phones are not a core science at this time.{{Citation needed}}
 The comic shows the galaxies of the universe as Samsung Galaxy mobile phones, pairing the age we see them at from earth, the degree they are redshifted, and how much of the sky they take up, known as their angular diameter. The mobile phones that are closer and older have depleted batteries, whereas the batteries are full for those phones from which the light is still only beginning to reach us. This is how galaxies appear in the sky if they were phones that had batteries lasting billions of years, the light reaching us from deeper into the past as it comes from objects that are farther away. Phones at a low battery may be a reference to [[1373: Screenshot]], where Randall commented that it is hard to pay attention to any phone with a low battery as the need to charge it is so urgent.
-An important takeaway from this comic is that the events that occurred at the very start of our universe are etched in our sky ''as if they are still happening now'', in a detailed faint timeline, that we are still learning more and more from.  Using the mobile phone metaphor helps as, when the technology space was young and smaller there were {{w|mobile phones}}, such as {{w|iPhone (1st generation)|the original iPhone}},  which one might still remember despite there being many more recent and better ones in a more crowded market space.
+An important takeaway from this comic is that the events that occurred at the very start of our universe are etched in our sky ''as if they are still happening now'', in a detailed faint timeline, that we are still learning more and more from.  Using the mobile phone metaphor helps as, when the technology space was young and smaller there were mobile phones, such as {{w|iPhone (1st generation)|the original iPhone}},  which one might still remember despite there being many more recent and better ones in a more crowded market space.
 Randall's intent appears to be to highlight how just a few very distant galaxies occupy incredibly large proportions of the sky and are seen as they were at a very young age. Mobile phones have this similarity, of massive presence, relatively early stages of new technology, and bringing information from far away.
-The large galaxies can be seen in dark red in the background as if the unimaginably ancient child galactic bodies are looming forebodingly behind everything else. The title text refers to galaxies falling into a pool of dilute blood.  This isn't what redshift actually is {{Citation needed}} (rather, it's an effect on the wavelength of light), but is an evocative comparison.
+The large galaxies can be seen in dark red in the background as if the unimaginably ancient child galactic bodies are looming forebodingly behind everything else. The title text refers to galaxies falling into a pool of dilute blood.  This isn't what redshift actually is{{Citation needed}} (rather, it's an effect on the wavelength of light), but is an evocative comparison.
 This physical concept has a lot of juxtaposition of things that usually contradict, and Randall has put energy into attempting to highlight that.

@@ Line 8: / Line 8: @@
 ==Explanation==
-This comic references multiple physics and maths concepts, including {{w|Angular diameter}}, {{w|Angular diameter distance}}, {{w|Redshift}}, and {{w|phones|mobile phones}}, although mobile phones are not a core science at this time.{{Citation needed}}
+This comic references multiple physics and maths concepts, including {{w|Angular diameter|angular diameter}}, {{w|Angular diameter distance|angular diameter distance}}, {{w|Redshift|redshift}}, and {{w|phones|mobile phones}}, although mobile phones are not a core science at this time.{{Citation needed}}
 The comic shows the galaxies of the universe as Samsung Galaxy mobile phones, pairing the age we see them at from earth, the degree they are redshifted, and how much of the sky they take up, known as their angular diameter. The mobile phones that are closer and older have depleted batteries, whereas the batteries are full for those phones from which the light is still only beginning to reach us. This is how galaxies appear in the sky if they were phones that had batteries lasting billions of years, the light reaching us from deeper into the past as it comes from objects that are farther away. Phones at a low battery may be a reference to [[1373: Screenshot]], where Randall commented that it is hard to pay attention to any phone with a low battery as the need to charge it is so urgent.

@@ Line 32: / Line 32: @@
 :(Brightness and redshift adjusted to keep phones visible)
 :Things that are far away look smaller, but things that are ''really'' far away look ''bigger'', because when their light was emitted, the universe was small and they were close to us.
-:[numerous iPhones scattered in space, with numbers visible on their lockscreen. The closest is brightly lit and says "13 billion years after the Big Bang" on the screen. Subsequent phones behind this one are smaller, fainter and more red, until they reach "3" (the rest of the text is too small to read). From this point, the phones grow larger, although they continue to get fainter and redder. Subsequent phones show "2", "1", "500 million", "200 million", "50 million", "20 million" (which is larger than the original "13 billion years after the Big Bang" phone) and a very large, faint phone so big that only the word "thousand" is visible, with the rest of the screen obscured behind other phones or so large it extends off the panel]
+:[numerous mobile phones scattered in space, with numbers visible on their lockscreen. The closest is brightly lit and says "13 billion years after the Big Bang" on the screen. Subsequent phones behind this one are smaller, fainter and more red, until they reach "3" (the rest of the text is too small to read). From this point, the phones grow larger, although they continue to get fainter and redder. Subsequent phones show "2", "1", "500 million", "200 million", "50 million", "20 million" (which is larger than the original "13 billion years after the Big Bang" phone) and a very large, faint phone so big that only the word "thousand" is visible, with the rest of the screen obscured behind other phones or so large it extends off the panel]

@@ Line 22: / Line 22: @@
 Katie Mack tweet: https://twitter.com/AstroKatie/status/1516548836709343238
-{{w|Spacetime diagram}} possibly has reasonable visualizations of the kinds of relations bodies have when they are moving this far apart, including angular diameter distance. Simultaneity no longer exists at such distances. Distance is debated too, although that would be a different article.
+A {{w|spacetime diagram}} possibly has reasonable visualizations of the kinds of relations bodies have when they are moving this far apart, including angular diameter distance. Simultaneity no longer exists at such distances. Distance is debated too, although that would be a different article.
 ==Transcript==

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 ==Transcript==
 :[Cueball and a row of 7 spiral galaxies, the first 5 growing sequentially smaller and the last 2 growing larger]
 :Angular Diameter Turnaround

@@ Line 39: / Line 39: @@
 {{comic discussion}}
 [[Category:Astronomy]]
 [[Category:Math]]
 [[Category:Physics]]

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 Randall's intent appears to be to highlight how just a few very distant galaxies occupy incredibly large proportions of the sky and are seen as they were at a very young age. Mobile phones have this similarity, of massive presence, relatively early stages of new technology, and bringing information from far away.
-The large galaxies can be seen in dark red in the background as if the unimaginably ancient child galactic bodies are looming forebodingly behind everything else. The title text refers to galaxies falling into a pool of dilute blood as if the void beyond were hell.  This completely misses the point as to what redshift is, being an effect on the wavelength of light, rather than light being filtered through regions of infernal suffering or far galaxies being stained by the blood of the enemies of Android phones.
+The large galaxies can be seen in dark red in the background as if the unimaginably ancient child galactic bodies are looming forebodingly behind everything else. The title text refers to galaxies falling into a pool of dilute blood as if the void beyond were hell.  This isn't what redshift actually is {{Citation needed}} (rather, it's an effect on the wavelength of light, rather than light being filtered through regions of infernal suffering or far galaxies being stained by the blood of the enemies of Android phones), but is an evocative comparison.
 This physical concept has a lot of juxtaposition of things that usually contradict, and Randall has put energy into attempting to highlight that.