56 AUSTRALIAN SKY & TELESCOPE July 2017
BERNHARD HUBLDARK TARGETS WITHIN THE WOLF
Object Mag(v) / Opacity RA
B228 6, 5 15 h 45.0m
Bernes 148 9.5 15 h 45.2m
SL 11 6 15 h 57.0m
NGC 5986 7.6 15 h 46.1m
SL 7 6 16 h 01.8m
SL 14 6 16 h 09.4m
B231 6 16 h 38.4m
B233 6 16 h 43.7m
Angular sizes and separations are from recent catalogues. Visually, an object’s size is often smaller than the
catalogued value and varies according to the aperture and magnification of the viewing instrument. Right
ascension and declination are for equinox 2000.0.four subgroups, catalogued as Lupus
1–4. We’ll focus here on Lupus 1, a
molecular cloud 450–500 light-years
from Earth and a member of our local
galactic neighbourhood (it’s found in
what’s known as Loop I, next to our
Local Bubble and just opposite the
famous Taurus Dark Cloud).
Sometimes referred to as the Dark
Wolf Nebula, Lupus 1 is dominated by
a long ridge of darkness several degrees
long and about 1° wide. Orientated
northwest–southeast, this tangled
absorption cloud was catalogued as
B228 by Barnard, who described it as
a “large vacant region... strongest
marked at the north end” in his
Catalogue of Dark Objects in the Sky.
The Sandqvist Lindroos catalogue
breaks Lupus 1 down into more
manageable pieces in terms of your field
of view: The northwest section of B228
is SL 12; the southeast section is SL
13. If you can manage a 1½ or 2° field
of view, you can compare SL 12 and SL
13 more easily. Like Barnard, Sandqvist
and Lindroos considered the northern
condensation to be darkest, classifying
SL 12 as a 6 on the opacity scale, with
SL 13 coming in at a 5.
Because molecular clouds are lively
star-forming regions, it’s not unusual
to find bright nebulosities — emission
nebulae, reflection nebulae, Herbig-
Haro objects — interrupting their deep
reaches. Observers of Lupus 1 will find
an interesting reflection nebula, Bernes
148 (GN 15.42.0), at roughly the
midway point of the dark spine of B228.
An estimated 3′ across, Bernes 148 is
visible at low power, and that’s how
you’ll want to find it, hopping off the
nearby brighter stars, Psi^2 (ψ^2 ) Lupi and
HD 140784. Low power will also help
you compare the brightness of Bernes
148 with the neighbouring stars. In my
estimation, it’s brighter than the stars
surrounding it.
To pull the nebula into clearer view,WBOLD AND BEAUTIFUL The yellow-orange
K-type star HD 143009 marks the western
edge of SL 7. Look for the triangular ‘bite’ of
stars cutting into the darkness to the southeast
of the star.Alt.ID
SL12,SL13
GN15.42.0
—
—
—
Bernes 149
—
—Size
240 ′× 20 ′
3. 0 ′
150 ′× 40 ′
9. 6 ′
60 ′× 10 ′
60 ′× 70 ′
50 ′× 40 ′
10 ′× 40 ′Dec.- 34 ° 31 ′
–34°17′ - 3 7° 4 8 ′
- 3 7° 47′
- 4 1° 2 0 ′
- 3 9° 08′
- 35 °2 5 ′
- 39° 49′
HD 143009DARK NEBULAESL 7