Editing 1231: Habitable Zone

{{comic
| number    = 1231
| date      = June 28, 2013
| title     = Habitable Zone
| image     = habitable zone.png
| titletext = They have a telescope pointed RIGHT AT US!
}}

==Explanation==
{{incomplete|The title text needs a rework. See discussion page.}}
While searching for {{w|extrasolar planet}}s this gullible astronomer is very excited because he believes he has found a planet in a star's {{w|habitable zone}}, with oceans and visible weather. From these observations, he has determined that it is quite likely to have life on it, which would be a major groundbreaking discovery.

The caption explains, however, that someone has used a mirror as a prank to fool the astronomer. The title text goes on says that the astronomer would also be able to see the reflection of his telescope, which would convinces him that there definately ''is'' intelligent life on the other planet, looking straight back at him no less! At its simplest, this comic is a suggestion for trolling astronomers (albeit in a practically impossible way).

There are quite a number of issues (listed below) with the practical implementation of this prank, so in order to subscribe to the simplistic explanation, the viewer must either be ignorant of, or choose to ignore these issues. It could be that the comic is designed such that viewers with different levels of understanding will 'get' the joke in a different way.

*In reality, the telescopes used for this type of research are designed to view faint, distant objects. In the images that they produce, objects the size of telescopes are not visible. Therefore, the astronomer would not see the reflection of the telescope.
*The telescopes have a motor that moves them to compensate for earth's rotation, so that they stay pointed on the same part of the sky.  This means that the telescope would not stay pointed at the mirror. The prankster would have to move the mirror in a very precise way to maintain the illusion.
*For the astronmer to have ascertained that the planet is in a star's habitable zone means that the astronomer observed the planet to be the size of Earth and observed the distance between the planet (Earth) and its star (the Sun), and the approximate size of that star. However, in a mirror at any reasonable distance from the earth, up to several times the distance of the moon, the earth would appear to be larger than the sun. 
*For the relative sizes of the earth and sun to be correct in the reflection, the mirror would have to be as far from earth as the mirror was from the sun. But even pointing to a mirror at a distance of the moon would require a real huge one, probably more than one hundred kilometers (sixty miles) in diameter.

Because Randall is doubtlessly aware of all these issues, it may be that the intended joke is not merely the prankster's deception of the astronomer, but the astronomer's self-deception.  Because the authenticity of the prank is so flimsy, a professional astronomer should be able to realize nearly instantaneously that they're not looking at an Earth-like, extrasolar planet (as should anyone, in fact, who is familiar with even the basic arrangement of Earth's continents and oceans).  As mentioned near the beginning of this section, however, many astronomers are understandably eager to locate other life-supporting planets.  This particular astronomer has proven so eager that he has thoughtlessly disregarded all the very obvious evidence to the contrary - an extreme example of {{w|confirmation bias}}.  Thus the comic may either be simply a humorous observation of the natural scientific appeal to be found in the idea of living or finding life outside our solar system, or a request that we ensure our eagerness to make these discoveries - understandable though it may be - does not unduly cloud our scientific judgment.

==Transcript==
:[Cueball stands in front of a huge telescope, looking through the eyepiece.]
:Cueball: I've discovered an Earth-sized planet in a star's habitable zone! It even has oceans! And visible weather!
:To mess with an astronomer, put a mirror in the path of their telescope.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Science]]
[[Category:Exoplanets]]