Questions tagged [notation]
The notation tag has no usage guidance.
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English Meaning for Abreviations (Easy Question)
I see a lot of publications where they use "code"/abbreviations but don't give the Laymans equivalents. Take https://academic.oup.com/view-large/127773013 from https://academic.oup.com/...
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What symbol is used for the moon when doing calculations?
When doing calculations the mass and radius of the Earth can be represented by $M_{\oplus}$ and $R_{\oplus}$ respectively.
The planets all have their own symbols which can easily be found online.
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What does Sa and Sab mean for spiral galaxies?
I have learned that the notation to classify spiral galaxies in the De Vaucouleurs system goes like "SA for spirals without bar, SB for spirals with bar and SAB for intermediate spirals". But in some ...
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Superscript-subscript uncertainty notation
While reading publications in astrophysics I've encountered this kind of notation (fictitious example):
$$M = 6.1^{+0.6}_{-0.1} \times 10^{30} \textrm{ kg}.$$
Several examples are here, p. 2.
I assume ...
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Who first used two lambdas to typeset the wavelengths of a spectra line doublet?
Also what is the accepted or most common way to typeset the wavelengths of a doublet? e.g. lambdalambda-3727,3729 with or without a hyphen? and without the Angstrom symbol?
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What abbreviations, letters, or symbols do we use to denote highly degenerate stars?
We have OBAFGKM to denote the strength of hydrogen lines.
Apparently we added S, N, C, and the W classes when we learned of new kinds of stars.
We use T, L, and Y to denote brown dwarfs.
The D ...
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Usage of $\sim$, $\approx$, $\simeq$, and $\cong$ in observational astronomy?
My understanding is $\sim$ generally means "on the order of magnitude of" e.g. $T \sim 10^5$ K
$\approx$ is obviously "approximately equal to" so for example one might write $d \approx 400$ pc rather ...
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From Mean Moon to True Moon in an old procedural calendar
This is a follow-up to How to interpret this old degree notation?
It is about an old calendar system which generates a luni-solar calendar with a procedural method, using a handful of calculations ...
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How to interpret this old degree notation?
I'm trying to follow the calculations in this paper on page 5 (see image below). The paper is describing traditional methods of calculation for a luni-solar calendar.
The math is not hard, but I can'...
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Name and language of symbol in astronomy book
I've been working on a programming project involving Peter Duffett-Smith's Practical Astronomy With Your Calculator (3rd Ed.), which has a large number of mathematical/astronomical formulas in it. ...
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