In an astronomy app name SkyPortal you can see the constellation lines as Modern or Traditional lines.

The traditional ones rarely have a resemblance to what they are a symbol of. However, the modern lines make much more sense.

Is there any reference for modern constellation lines? Any online resource to show or discuss them?

enter image description here

enter image description here

I was under the impression that these lines are historical. Just after asking this question, I looked at the images on the Book of Fixed Stars and realized the original book doesn't have the lines at all. So these lines are something new.

The Book of Fixed Stars

  • $\begingroup$ Older Western star atlases (Bayer 1603, Hevelius 1687, Flamsteed 1729) used such illustrations too. $\endgroup$
    – Mike G
    Commented Jul 7, 2023 at 21:10
  • $\begingroup$ In case anyone was confused by the last picture (from the Book of Fixed Stars), I'm pretty sure it's a mirror image! The 6 leftmost stars, making up the bow, are μ, γ, η, λ, δ, and ε; in the first two images, those stars form a group of six connected by lines, at the top in the first image and the lower right in the second image. In the last picture, both the upper part of the bowstring and the arrow lead to the "teapot handle" of φ, σ, τ, and ζ; the second picture shows the "arrow" connecting from φ to δ, but the first picture connects φ to λ instead. $\endgroup$ Commented Jul 8, 2023 at 21:18
  • $\begingroup$ Related: Why do some images depict the same constellations differently? $\endgroup$
    – pela
    Commented Jul 9, 2023 at 19:53

3 Answers 3


In the book The Stars: A New Way to See Them, HA Rey redrew the stick figures to be much more sensible. This is the source of many of the "modern" or "western" versions used by many applications.

There is no "official" source of constellation lines. The IAU does define specific boundaries, but no stick figures.

Here is an extract of the stick figures used by Stellarium for the "Western" culture.


The constellation lines in question resemble two of the "sky cultures" available in Stellarium:

Another choice is:

Data for these are in the Stellarium GitHub repository, in files named constellationship.fab.

Ian Ridpath credits Ruelle 1786 and Dien 1831 for the first uses of connecting lines instead of illustrated figures. In any case, the lines are the cartographer's choice. The only official standard is the boundary, shown in red in all three images here.


There are no official "modern" lines, or official "traditional" lines. Both are just choices for asterisms that the app developer made. You'd probably have to look into the credits or ask the developers to find out what sources the app developers used to draw them.

The IAU designated constellation boundaries were developed in 1922 to make sure every point of the sky was contained within a unique constellation, but there aren't any official lines inside those.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .