Nell'immagine qui sopra si osserva l'ammasso globulare M 71 - NGC 6838, situato nella costellazione della Freccia (Sagittae, la Sagitta). Quest'ammasso globulare ha la particolarità di mostrare le stelle risolte fino alla parte più interna dell'oggetto, è ottava magnitudine complessiva, ma non appare come un'oggetto molto evidente. Nella ripresa di Rubes Turchetti le su stelle appaiono prevalentemente di colorazione gialla.

Qui sotto riporto le note fornite dal nostro planetario, il Guide 8.0:

Commenti tratti dal Progetto NGC-IC:
Ammasso globulare
Tipo: GCL
Asc. retta: 19 53 46.1 (J2000)
Declinazione: +18 46 42
Magnitudine: 8.2
Asse maggiore: 6.10 minuti d'arco
Costellazione: SGE
Designazioni alternative:
M 71            GCL 115
Asc. retta: 19h53m46.1s
Declinazione: +18 46' 41"

Note dal Catalogo NGC2000:
J2000 AR: 19h53.8m
J2000 dec: +18 47'
Cl, vL, vRi, pmC, st 11...16; = M71

NGC 6838: cluster, very large, very rich in stars, pretty
much compressed, stars 11...16; = M71


Commenti dalle Osservazioni di Steve Coe:

NGC 6838 (M 71)  This compact star cluster has been called an open and
a globular.  It is bright, pretty large, very rich and much compressed
at 135X.  At 165X on a good night, I can see an arrowhead shape to the
cluster and count 56 stars across the mottled face of this cluster.
The cluster is easy to pick out of the Milky Way with the 11 X 80
finder.  I have observed this object in several large scopes and it is
always difficult to determine where the cluster stops and the
background stars begin. In the Lines' 20" f/6 at 150X and in the Lowell
Observatory 24" Clark refractor at 380X this very compact cluster was
fascinating.  There are many curving lines of stars with dark lanes
between them.  Camp 613 13" 10/10-- seen in 11X80, 100X--bright,
pretty large, rich, very much compressed, somewhat brighter middle,
220X--28 stars counted, arrowhead shape points east, several close
double stars involved, averted vision really fills in stars.  There
is a silvery face of unresolved stars to the cluster that is
fascinating.  One of the pairs of stars is right at the middle, it
is split but only 2023155310f the time.  In a very rich field of view,
440X--57 stars counted and the matched double in the middle is
constantly split now.  This excellent high power view is all that
the 13 inch will show of this object.  Great night.
Ultimate Star Party, McDonald Obs. S=6, T=8, 36" f/5--
M 71;  82 stars resolved;  arrowhead shape obvious;  dark lane comes in from
right side.  Several small groupings of stars and lots of stars at the limit
of resolution give a glowing background.
M 71  in 25" with 12mm eyepiece, 68 stars on "left half" of cluster, a blue
and gold pair near the center.  Lots of dark lanes surround the cluster and
on one side the darkness stops the cluster completely.


Commenti tratti dal SAC (Saguaro Astronomy Club) 7.2:
NGC 6838
M  71
Tipo di oggetto: GLOCL
Costellazione: SGE
Asc. retta: 19 53.8 (J2000)
Declinazione: +18 47
Dimensioni: 6.1
Cl,vL,vRi,pmC,*11...16
Arrowhead shape, stars have few metals

L'immagine ha una dimensione di 528 x 513 pixel; è a 16,8 milioni di colori ed occupa 1,5 MB, qui compressi a 98 kB. La risoluzione dell'immagine è di 2.35"/pixel.