and Pollux. It is of type M, and obviously red; its distance
is 166 light-years, and it is 120 times as luminous as the
Sun. None of the other stars in Lynx have been given
Greek letters, though one of them, 31 Lyncis, has been
dignified with a proper name: Alsciaukat.
The globular cluster NGC2419 (C25), about 7 degrees
north of Castor, is faint and none too easy to identify. This
is not because it is feeble – on the contrary it is exception-
ally large, and must be around 400 light-years across – but
because it is so far away.
The distance has been estimated at around 300,000
light-years, and though this may be rather too great it is
clear that the cluster is at the very edge of the Milky Way
system. It may even be escaping altogether, in which case
it will become what is termed an intergalactic tramp. It is
very rich, and, predictably, its leading stars are red and
yellow giants.
We have little direct knowledge of the isolated star
systems that lie between the galaxies. There is every
reason to believe they exist, but since they will be so
much less luminous than full-scale galaxies they will be
far less easy to detect.
Indeed, galaxies of very low surface brightness may
also be very elusive. Modern electronic techniques used
with large telescopes may be able to track these isolated
objects, but at the moment we do not know how many of
them there are. At least it seems unlikely that NGC2419
will become the only intergalactic tramp.STAR MAP 18
AE Aurigaeis an irregular
variable star within the
constellation Auriga. This
spectacular image was
obtained by the 0.9-m
(36-inch) telescope at the Kitt
Peak National Observatory.
AE Aurigae is the bright bluestar in the centre of the
image, and it is is
surrounded by what is
known as the Flaming Star
Nebula. This false-colour
image was created by
combining images taken in
three different wavelengths.BRIGHTEST STARS
No. Star R.A. Dec. Mag. Spectrum Proper name
hm s ° ‘ “
13 · 05 16 41 45 59 53 0.08 G8 Capella
34 ‚ 05 59 32 44 56 51 1.90 A2 Menkarlina
37 ı 05 59 43 37 12 45 2.62 A0p
3 È 04 56 59 33 09 58 2.69 K3 Hassaleh
7 Â 05 01 58 43 49 24 2.99v F0 Almaaz
10 Ë 05 06 31 41 14 04 3.17 B3
Also above magnitude 4.3: ‰(3.72), ̇(Sadatoni) (3.75) (max).
VARIABLES
Star R.A. Dec. Range Type Period Spectrum
hm °’ (mags) (d)
 05 02.0 43 49 3.0–3.8 Eclipsing 9892 F
̇ 05 02.5 41 05 3.7–4.1 Eclipsing 972 KB
UU 06 36.5 38 27 5.1–6.8 Semi-reg. 234 N
DOUBLE
Star R.A. Dec. P.A. Sep. Mags
hm °’ ° “
ı 05 59.7 37 13 AB 313 3.6 2.6,7.1
AC 297 50.0 10.6
CLUSTERS AND NEBULAE
MCNGC R.A. Dec. Mag. Dimensions Type
hm °’ ’
36 1960 05 36.1 34 08 6.0 12 Open cluster
37 2099 05 52.4 32 33 5.6 24 Open cluster
38 1912 05 28.7 35 50 6.4 21 Open cluster
1857 05 20.2 39 21 7.0 6 Open cluster
31 IC405 05 16.2 34 16 var 30 19 Nebula: Flaming
Star Nebula,
round AE AurigæBRIGHTEST STAR
No. Star R.A. Dec. Mag. Spectrum Proper name
hm s ° ‘ “
40 · 09 21 03 34 23 33 3.13 MO
Also above magnitude 4.3: 38 (3.92), 31 (Alsciaukat) (4.25).
CLUSTERS AND NEBULAE
MCNGC R.A. Dec. Mag. Dimensions Type
hm °’ ’
25 2419 07 38.2 38 53 10.4 41 Globular cluster
2683 08 52.7 33 25 9.7 9.3 2.5 Sc galaxyAURIGALYNXGb Atl of Univ Phil'03stp 2/4/03 7:43 pm Page 253