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| Binary Star |
 Title text: The discovery of a fully typographical star system comes with a big asterisk. |
Explanation
While a main sequence star is a real celestial object, a five-pointed star is how stars are often drawn. The comic uses a drawn star shape to be a part of a celestial star system. Binary star systems are common throughout the universe, where two stars orbit each other. In some cases, these are different types of stars, such as a neutron star orbiting a main sequence star. The comic depicts a binary system of a real star and a drawn star.
In reality, pointed stars do not actually exist. The points often seen in the night sky around stars are just optical illusions caused by the diffraction spike effect.
Drawing a star as a pentagram, as shown in the comic, is referenced in 1029: Drawing Stars.
The orbital paths shown are anomalous. The "main sequence star" follows a path that's nearly circular, while the five-pointed star follows an elliptical path, and they're at different locations along their paths. If the two stars were the most massive objects in their system by a significant margin, approximating a two-body system, their paths should be the same shape (albeit at different sizes, if their masses differ) and their locations along those paths should be in phase. This implies that there's at least one other massive object in the system, which isn't shown. The much smaller path of the "main sequence star" suggests that it's in a (relatively) close orbit with the other massive object, with the five-pointed star being much less massive than either, and essentially orbiting them at a greater distance.
The title text similarly uses the * symbol (an asterisk - meaning little star), which is sometimes called a star, to be another real celestial star. A "big asterisk" is used as a metaphor for a rather large caveat, symbolizing a long footnote. The title text says "big asterisk" to mean a physically very large (astronomical scale) punctuation symbol.
Transcript
- [Graphical depiction of a binary star system. The orbits are shown with dashed lines. One star is revolving circularly close to the center of mass and is shown as a filled circle. The other has a very elliptic orbit further out. It is currently close to its furthest point from the other star. This star is depicted as a pentagram.]
- [Caption below the image:]
- Space news: astronomers have found the first known system with a main-sequence star orbited by a five-pointed one.
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