Questions tagged [notation]

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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 from
MiscellaneousUser's user avatar
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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. ...
Kantura's user avatar
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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 ...
Elismar Lösch's user avatar
9 votes
1 answer

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 ...
pglpm's user avatar
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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?
Chris's user avatar
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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 ...
MackTuesday's user avatar
12 votes
4 answers

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 ...
imanorc's user avatar
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4 votes
1 answer

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 ...
Gambhiro's user avatar
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3 votes
2 answers

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'...
Gambhiro's user avatar
  • 237
2 votes
1 answer

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. ...
nerdenator's user avatar