2596: Galaxies

2022-03-22T12:43:36Z

RMMentock:

{{comic
| number = 2596
| date = March 21, 2022
| title = Galaxies
| image = galaxies.png
| titletext = I know it seems overwhelming, but don't worry; I'm sure most of them have only a few stars, and probably no planets.
}}

==Explanation==
{{incomplete|Created by a A GALAXY CONTAINING ONLY ONE PLANET. Do NOT delete this tag too soon.}}
This is another comic with a [[:Category:Facts|Fact]], the second in a row of these fact comics to use an Astronomy fact.

"Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is." ― {{w|Douglas Adams}}, {{w|The Hitchhiker's Guide to the Galaxy}}

Our best approximation of the number of {{w|galaxies}} in the {{w|observable universe}} is about 200 billion. 2 × 10^11 is a lot of galaxies, and here [[Randall]] exemplifies this by showing a small circle and estimating that when the comics picture is viewed at arm's length, full screen on your smartphone, the circle contains roughly 50,000 galaxies.

The dot size is subjective, but it can reasonably be taken to be 1mm diameter. The area of a sphere at arm’s length (about half meter) would be pi meter squared. Thus, the area of the circle is about 1/4000000 of the area of the sphere, 200 billion galaxies divided by 4 million is the 50,000 average mentioned in the cartoon.

While galaxies usually are between 3,000 to 300,000 {{w|light-years}} across and contain between 10^8 (100 million) and 10^14 (100 trillion) stars, most are so far away from the Earth (upwards of millions of light-years) that they are invisible to the naked eye, or even through most telescopes. When magnified across such vast distances, even something as small as a pinhole expands to huge sizes, easily able to fit tens of thousands of galaxies.

The premise of this comic is that although galaxies are giant, space is <i>unimaginably</i> big and contains a vast number of things. Randall is apparently overwhelmed by this, as shown in the caption: ''Astronomy Fact: There are too many galaxies''.

The title text is Randall reassuring his readers why not to worry of this overwhelming fact. He states that most galaxies only have few stars and probably no planets. However, as mentioned above each galaxy contains a huge amount of stars, and as evident from all his own comics about [[:Category:Exoplanets|exoplanets]], it is now clear that many of the stars in a galaxy also have planets orbiting them. Thus the number of stars and planets in that small circle is much more mind-bogglingly large, than the number of galaxies, and thus the reassurance is sarcasm.

In [[975: Occulting Telescope]] [[Cueball]] expresses a similar sentiment about the number of stars.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
[Caption near the top of the panel:]
Open this picture fullscreen on your phone and hold it at arm's length.

[A very small circle is in the center of the panel, with an arrow pointing towards it and leading away to a caption below]

There are 50,000 galaxies in this circle.

[Caption below the panel:]
Astronomy Fact: There are too many galaxies.

{{comic discussion}}

[[Category:Facts]]
[[Category:Astronomy]]

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2596: Galaxies