3243: Crystal Gazing

2026-05-08T21:24:02Z

207.195.86.164: /* Explanation */

{{comic
| number = 3243
| date = May 8, 2026
| title = Crystal Gazing
| image = crystal_gazing_2x.png
| imagesize = 281x397px
| noexpand = true
| titletext = 'Beyond that lies a vale of fire through which my vision cannot penetrate' is the kind of fun thing geologists, heliophysicists, and early universe cosmologists have a lot of opportunities to say.
}}

==Explanation==
{{incomplete|This page was created over 4.54 billion nanoseconds ago. Don't remove this notice too soon.}}

A geologist dressed up as a wizard (assuming that isn't how they normally dress{{citation needed}}) announces — in archaic language befitting his costume — that he has determined the {{w|age of the Earth}} by analyzing {{w|zircon}}. Zircon is a crystal with the formula ZrSiO<sub>4</sub>. During its formation it can incorporate uranium instead of zirconium in its crystal lattice, but cannot incorporate lead. The uranium then decays (via several intermediates) into lead. Thus a sufficiently old zircon crystal will contain some lead, allowing geologists to calculate its age. This method is especially reliable since uranium-238 decays into lead-208 with a half-life of 4.5 billion years, while uranium-235 decays into lead-207 with a half-life of 0.7 billion years, allowing geologists to determine the age even if some lead was lost from the crystal.

A prophet of doom is someone who predicts impending disasters, especially the end of the world. The joke in the caption is that someone who can determine when the world began is just doing this in reverse, and that's what geochronologists are doing when they calculate the age of the Earth.

The title text points out, in similar flowery language (in keeping with the character being a Tolkienesque portrayal of a wizard, where [https://tolkiengateway.net/wiki/Vales_of_Anduin vales] are part of the geographical language), that many areas of physical sciences are limited in how far back they can describe the world or universe. {{w|Geologists}} are limited by the age of the Earth (and maybe even to some time after that, as we have little evidence of its original molten form), {{w|heliophysicists}} can't determine the early nature of the Sun, and early universe {{w|cosmologists}} don't know what was happening during and before the {{w|big bang}}.

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}

:[A character in wizard garb with long beard and hair talks to Cueball. To the left of the wizard is a chart with two lines intersecting.]

:Wizard: By gazing into my crystals of zircon, I have divined the date of the hour of fire marking the limit of this world's existence.
:Wizard: 4.54 billion years ago, the beginning was nigh!

:[Caption below comic:]
:Geochronologists are just reverse prophets of doom.

{{comic discussion}}<noinclude>
[[Category:Geology]]
[[Category:Comics featuring Cueball]]

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3243: Crystal Gazing