YOUR observations.
The July 1995 "Astronomy" magazine has an excellent
article on sketching and the drawing techniques that can be used
to duplicate what you see at the eye-piece.
M 36 (in Auriga)
North is up
10" Schmidt-Cassegrain telescope at 62x
December 29, 1994
Fairly bright. Not quite
as rich as M 35. Has a star shape. The brighter stars are main
sequence, B-type. This cluster is one of three bright clusters
in the constellation Auriga. It is the smallest, but brightest.
If it were 10 times closer, the cluster would be as bright as
the Pleiades. It would make a spectacular sight if it were this
close because it's diameter is about twice that of the Pleiades
cluster.
Click here to view full sketch of M36 (16000
bytes)
NGC 2264 (in
Monoceros)
North is up
10" Schmidt-Cassegrain telescope at 40x
March 2, 1995
At only 3 million years old,
this is one of the youngest clusters known and contains many
pre-main sequence stars. And, like the Orion nebula, it is a
region where stars are still forming. The brightest star is S
Moneceros, a variable double star. It's photographic magnitude
varies from 4.2 ->4.6. This star has a computed absolute magnitude
of about -5 (about the brightness of 8500 suns).
Click here to view full sketch of NGC2264
(4275 bytes)
M 45 (the Pleiades)
8x56 binoculars
September 26, 1994
Only 423 light years away.
The stars are very young - they condensed from a nebula about
20 million years ago. The dinosaurs died out 63 million years
ago and would not have seen these stars. The brightest star is
Alcyone, a star 1000 times brighter than the sun and is probably
10 times bigger in size. The nine brightest stars are all B-type
giants. The cluster is only 7 light years in diameter.
Click here to view full sketch of M45 (6017
bytes)
M 42 (the Orion Nebula)
10" Schmidt-Cassegrain telescope at 62x, no filter
December 29, 1994
EXTRA-ORDINARY! Very beautiful,
quite extensive. It showed lovely mottled bits. The trapezium
and three stars below stand out like jewels set against a spun
gossamer backdrop. This nebula is the middle "star"
in Orion's sword. When your eyes have adapted to the dark, binoculars
will let you see a glowing gray-green mist.
Click here to view full sketch of M42 (18480
bytes)
NGC 457 (in Cassiopeia)
10" Schmidt-Cassegrain telescope at 62x
August 31, 1995
NGC 457 - or the Owl Cluster
in Cassiopeia is located 4 degrees southeast of gamma Cassiopeia.
This young (8 million years old) cluster is approximately 9,300
light years away and is at least 30 light years across. The cluster
probably contains several thousand stars but because of the distance
only about 100 are brighter than magnitude 13. Our Sun at this
distance would be magnitude 17.3 !
There are two bright super giants in the cluster. These are
stars that have left the main sequence and are in the final stage
of their evolution. One of them, Phi Cassiopeia with a visual
magnitude of +5 has an absolute magnitude of -8.8. This means
that this star is about 25 times as massive and 275,000 times
as bright as our Sun. It is the type of star that scientists
believe will generate a Type II supernova.
Click here to view full sketch of NGC
457 (5798 bytes)
Zeta Perseus (in Perseus)
10" Schmidt-Cassegrain telescope at 96x
November 19, 1995
Zeta Perseus with a visual
magnitude of +2.8 is located at the south end of the constellation
of Perseus. It is a young supergiant star that is a member of
young association of stars. This association expanding outward
from a common point of origin is called the Perseus OB 2 association.
Less than a million years old this association is located about
1,300 light years away and is approximately a hundred light years
across. It contains 20 stars brighter than visual magnitude +6
in an area of sky about 8 degrees by 5 degrees. This young cluster
is also associated with nebulosity including the famous California
Nebula.
Zeta Perseus A component at a distance of 1,600 light years
is about 15,000 times as luminous as the Sun and is known to
be a spectroscopic binary. The second star or B component of
this double is located 12.9 seconds to the south west of Zeta
and appears to have the same proper motion. Both stars appear
white and the predicted distance between Zeta A and B would be
4,000 + AU.
Click here to view full sketch of Zeta
Perseus (8122 bytes)
