2828: Exoplanet Observation

2023-09-13T22:37:50Z

Burnsides: American specter over spectre, and / instead of \

{{comic
| number = 2828
| date = September 13, 2023
| title = Exoplanet Observation
| image = exoplanet_observation_2x.png
| imagesize = 295x272px
| noexpand = true
| titletext = NASA prefers to say that their rovers are 'looking for signs of past life on Mars' and not 'ghost hunting.'
}}

==Explanation==
{{incomplete|Created by an ALIEN GHOST EXORCIST - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

{{w|Spectroscopy|Spectral analysis}} as used in the study of {{w|exoplanet}}s and other distant objects in space refers to using the intensities of different frequencies of light (and other electromagnetic frequencies) from stars which they occlude to infer data about their chemical composition. This is used to detect certain gases in the atmosphere, such as {{w|Oxygen#Allotropes|free oxygen}}, which might suggest generation by and for Earth-like life. On the day before this comic was published, {{w|NASA}} announced that spectral analysis of the exoplanet {{w|K2-18b}} showed abundance of {{w|methane}} and {{w|carbon dioxide}}, and shortage of {{w|ammonia}}, which are chemical footprints that support the hypothesis that it may have a life-supporting water ocean; and there was possible detection of {{w|dimethyl sulfide}}, which on {{w|Earth}} is only produced by life.[https://www.nasa.gov/goddard/2023/webb-discovers-methane-carbon-dioxide-in-atmosphere-of-k2-18b] The word spectral as in spectral analysis refers to the {{w|electromagnetic spectrum}}. If confirmed, these would be very interesting scientific facts that would definitely drive further scrutiny, although it may yet turn out to be less remarkable {{w|Life on Venus#Phosphine|on closer study}}.

"Spectral" is also a term sometimes used as a descriptor/adjective: to originate from (or exhibit properties of) supposed ghosts or "specters". "Specter" and "spectrum" have the same etymological root, deriving from Latin "spectrum" meaning "appearance", with a specter specifically referring to a visible shadow or ghost. This comic leverages this pun, to humorously suggest that close study of exoplanetary shading could present a reasonable method of hunting for such ghosts:

In this comic, Cueball states that the specific reductions in detected light are theorized to indicate the presence of ghosts/specters in the planet's atmosphere, similar to how gases or suspended particles absorb certain wavelengths. Like many atmospheric gases, ghosts/specters are frequently presumed to be invisible under most conditions.{{Citation needed}} However, if these specters have their own absorption spectrum distinguishing them from ordinary gases, the presence of such specters in an exoplanet's atmosphere could be considered evidence of (past) alien life.

The title text refers to the search for past life on Mars. It humorously conflates the practice of searching for signs of past life, such as specific molecules or fossils (which NASA does actively search for), versus the disreputable practice of searching for evidence to support the existence of ghosts, with this conflation framing both as an equally scientific indication of past life. In a very loose sense, real signs such as gases or fossils could be considered "ghosts" of past life.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:: [Cueball is holding a stick and pointing at a slide with two ghosts and a planet]
:: Cueball: When the planet passed in front of its host star, some of the light was absorbed by ghosts, indicating that the planet is likely haunted.

:: [Caption below the panel]
:: Exoplanet Spectral Analysis

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Astronomy]]
[[Category:Exoplanets]]
[[Category:Aliens]]
[[Category:Puns]]

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2828: Exoplanet Observation