Caption: The Greek alphabet of
24
Greek letters:
alpha α,
beta β,
gamma γ, ...
In astronomy,
some Greek letters
turn up fairly often:
- α,
β,
γ,
and
δ turn up
in
Bayer designation system for
bright stars
and in designating the
hydrogen Balmer lines.
-
θ is the conventional symbol
for angle.
- λ is the conventional symbol
for wavelength.
- μ is the
metric prefix meaning 10**(-6).
- π the letter
is the symbol for the
irrational number
Pi: π = 3.14159265358979 ...
(see One Million Digits of Pi).
- And others as need arises.
- Actually all small Greek letters
are used in the aforesaid Bayer designation system
to label stars in a given
constellation in order of their
apparent magnitude
(approximately their
apparent V magnitude):
the brightest one was called α,
the 2nd brightest one was called β,
etc.
The ordering by brightness is NOT always correct.
Johann Bayer (1572--1625) and other early
implementers of the Bayer designation system
did NOT work at modern
accuracy/precision.
When these implementers ran out of
Greek letters they used
Roman letters and in later times
numbers were used too.
So even omicron ο is used
astronomy even though it looks
almost like o.
This is well known to Star Trek
fans: see
How to Pronounce "Omicron" the Star Trek Way | 0:30.
Actually, all astronomers
and physicists
can read Greek---we
just don't know what the words mean.
But sometimes we do:
το
δημοσ
means "the people" as in
"We the people".
Indeed,
Almost all the Greek letters,
upper-case and
lower-case,
have conventional uses in mathematics,
science,
and engineering:
see
Wikipedia:
Greek letters used in mathematics, science, and engineering.
For reference, the complete Greek alphabet:
English
spelling /
upper-case /
lower-case,
pronunciation of name (NOT sound):
1) alpha Α α,
pronounced alpha,
2) beta Β β,
pronounced beta,
3) gamma Γ γ,
pronounced gamma,
4) delta Δ δ,
pronounced delta,
5) epsilon Ε ε,
pronounced epsilon,
6) zeta Ζ ζ,
pronounced zeta,
7) eta Η η,
pronounced eta,
8) theta Θ θ,
pronounced theta,
9) iota Ι ι,
pronounced i-ota,
10) kappa Κ κ,
pronounced kappa,
11) lambda Λ λ,
pronounced lam-da,
12) mu Μ μ,
pronounced mu,
13) nu Ν ν,
pronounced nu,
14) xi Ξ ξ,
pronounced Zi,
15) omicron Ο ο,
pronounced omicron,
16) pi Π π,
pronounced pi,
17) rho Ρ ρ,
pronounced ro,
18) sigma Σ σ,
pronounced sigma.
19) tau Τ τ,
pronounced tao,
20) upsilon Υ υ,
pronounced upsilon,
21) phi Φ φ,
pronounced phi,
22) chi Χ χ,
pronounced ky,
23) psi Ψ ψ,
pronounced sy,
24) omega ω,
pronounced omega.
Additionally, there
are archaic Greek alphabets.
The only archaic Greek letter
that gets a modern conventional use seems to be
digamma Ϝ (which looks a lot like F),
pronounced digamma
(see
Wikipedia:
Greek letters used in mathematics, science, and engineering: Digamma).
Credit/Permission: ©
David Jeffery,
2003 / Own work.
Image link: Itself.
Local file: local link: greek_alphabet.html.
File: Hellas file:
greek_alphabet.html.