Astronomy

3.25 3.5

Pandora’s Cluster

3.52 billion light-years

WWW.ASTRONOMY.COM 31

Scientists think our gal-

axy has four major spiral

arms that wind their way

out from a central bar. The

Sun lies approximately

27,200 light-years from

the center. NASA/JPL-CALTECH/R.

HURT (SSC-CALTECH)

Sc

u

tu

m

• C
  e
  n
  ta
  u
  ru
  s

(^) A
rm
(^)
(^)
P
e
rs
e
u
s^
A
rm
Central bar
C
a
ri
n
a

• S

a

g

it

ta

ri

u

s

A

mr

N

or

m

a-

Ou

ter

(^) Arm
Sun
ESO/D. COE (STS
CI)/J. MERTEN (HEIDELBERG/BOLOGNA)
(PANDORA’S CLUSTER)