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(IAAC) Obj: M8, M20, ngc 6530 - Inst: Naked eye, 7x50 binoculars



Observer: Lew Gramer
Your skills: Intermediate
Date and UT of Observation: 1997-07-4/5, 03:45 UT
Location: Savoy, MA, USA (42N, elev 700m)
Site classification: rural
Limiting magnitude: 7.1 (zenith)
Seeing: 5 of 10 - mediocre, near total cumulus
Moon up: no
Instrument: Naked eye, 50mm Simmons binoculars
Magnification: 1x, 7x
Filters used: None
Object: M8, M20, ngc6530 (globular ngc6544 not seen)
Category: Reflection nebulae and open cluster
Constellation: Sgr
Data: mags 4.6, 6.3, 4.6  sizes 80'x40', 28', 15'
RA/DE: 18h00m  -24o
Description:
Two bino fields (8o) due N of Sgr's teapot spout, and arrayed
about the line formed by the mag 4-6 stars 4, 7 and 9 Sgr and
the blurry open cluster n6530. M8 and M20 fall easily in the
same field, forming between them a beautiful complex of BRIGHT
haze and intermingled field stars. The dark bar running through
the center of M8 was readily apparent even at 7x, as was some
mottling whenever averted, concentrated vision was used. M20
to the N appeared much fainter, and (more suprisingly) larger
than M8, and often required averted vision to see. No detail
could be discerned in the extended haze. Interestingly, back-
ground stars in this field were so thick and poorly resolved
that they seemed to form a "bridge" of nebulous light between
and among the two brighter (M8) & fainter (M20) true nebulae.
No note of globular ngc 6544, SE of M8, was made at the time.