NGC 6991 is an open cluster in Cygnus
NGC 6991 is an open cluster in the constellation Cygnus . Spans 23′. It is a telescope object, 6 inches or larger, and it is highest in the evening sky in September.
Open cluster: a loose group of a few dozen to a few thousand young stars born together from one cloud of gas. They drift apart over a few hundred million years and lie in the disk of the Milky Way.
Finding NGC 6991 from Deneb
Deneb
NGC 6991
CYGNUS
NGC 6991 lies 3.2° northeast of Deneb , the magnitude 1.3 star. Three fingers held at arm's length cover about 5°.
NGC 6991 is highest in the evening in September
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
60°N
JAN at 60°N: 29° high at 9 pm FEB at 60°N: 21° high at 9 pm MAR at 60°N: 18° high at 9 pm APR at 60°N: 19° high at 9 pm MAY at 60°N: 26° high at 9 pm JUN at 60°N: 37° high at 9 pm JUL at 60°N: 51° high at 9 pm AUG at 60°N: 66° high at 9 pm SEP at 60°N: 77° high at 9 pm OCT at 60°N: 71° high at 9 pm NOV at 60°N: 56° high at 9 pm DEC at 60°N: 42° high at 9 pm 50°N
JAN at 50°N: 22° high at 9 pm FEB at 50°N: 12° high at 9 pm MAR at 50°N: 8° high at 9 pm APR at 50°N: 10° high at 9 pm MAY at 50°N: 18° high at 9 pm JUN at 50°N: 32° high at 9 pm JUL at 50°N: 48° high at 9 pm AUG at 50°N: 67° high at 9 pm SEP at 50°N: 86° high at 9 pm OCT at 50°N: 73° high at 9 pm NOV at 50°N: 54° high at 9 pm DEC at 50°N: 37° high at 9 pm 40°N
JAN at 40°N: 14° high at 9 pm FEB at 40°N: 2° high at 9 pm MAR at 40°N: -2° high at 9 pm APR at 40°N: 0° high at 9 pm MAY at 40°N: 10° high at 9 pm JUN at 40°N: 25° high at 9 pm JUL at 40°N: 43° high at 9 pm AUG at 40°N: 64° high at 9 pm SEP at 40°N: 82° high at 9 pm OCT at 40°N: 71° high at 9 pm NOV at 40°N: 50° high at 9 pm DEC at 40°N: 31° high at 9 pm 30°N
JAN at 30°N: 6° high at 9 pm FEB at 30°N: -7° high at 9 pm MAR at 30°N: -12° high at 9 pm APR at 30°N: -9° high at 9 pm MAY at 30°N: 1° high at 9 pm JUN at 30°N: 18° high at 9 pm JUL at 30°N: 38° high at 9 pm AUG at 30°N: 58° high at 9 pm SEP at 30°N: 72° high at 9 pm OCT at 30°N: 64° high at 9 pm NOV at 30°N: 44° high at 9 pm DEC at 30°N: 25° high at 9 pm 20°N
JAN at 20°N: -1° high at 9 pm FEB at 20°N: -16° high at 9 pm MAR at 20°N: -22° high at 9 pm APR at 20°N: -19° high at 9 pm MAY at 20°N: -7° high at 9 pm JUN at 20°N: 11° high at 9 pm JUL at 20°N: 31° high at 9 pm AUG at 20°N: 50° high at 9 pm SEP at 20°N: 62° high at 9 pm OCT at 20°N: 56° high at 9 pm NOV at 20°N: 38° high at 9 pm DEC at 20°N: 18° high at 9 pm 10°N
JAN at 10°N: -9° high at 9 pm FEB at 10°N: -25° high at 9 pm MAR at 10°N: -32° high at 9 pm APR at 10°N: -29° high at 9 pm MAY at 10°N: -15° high at 9 pm JUN at 10°N: 4° high at 9 pm JUL at 10°N: 24° high at 9 pm AUG at 10°N: 42° high at 9 pm SEP at 10°N: 52° high at 9 pm OCT at 10°N: 47° high at 9 pm NOV at 10°N: 30° high at 9 pm DEC at 10°N: 11° high at 9 pm 0°
JAN at 0°: -17° high at 9 pm FEB at 0°: -34° high at 9 pm MAR at 0°: -42° high at 9 pm APR at 0°: -38° high at 9 pm MAY at 0°: -23° high at 9 pm JUN at 0°: -4° high at 9 pm JUL at 0°: 16° high at 9 pm AUG at 0°: 34° high at 9 pm SEP at 0°: 42° high at 9 pm OCT at 0°: 38° high at 9 pm NOV at 0°: 23° high at 9 pm DEC at 0°: 3° high at 9 pm 10°S
JAN at 10°S: -25° high at 9 pm FEB at 10°S: -43° high at 9 pm MAR at 10°S: -52° high at 9 pm APR at 10°S: -47° high at 9 pm MAY at 10°S: -31° high at 9 pm JUN at 10°S: -11° high at 9 pm JUL at 10°S: 8° high at 9 pm AUG at 10°S: 25° high at 9 pm SEP at 10°S: 32° high at 9 pm OCT at 10°S: 28° high at 9 pm NOV at 10°S: 14° high at 9 pm DEC at 10°S: -4° high at 9 pm 20°S
JAN at 20°S: -32° high at 9 pm FEB at 20°S: -51° high at 9 pm MAR at 20°S: -62° high at 9 pm APR at 20°S: -56° high at 9 pm MAY at 20°S: -39° high at 9 pm JUN at 20°S: -18° high at 9 pm JUL at 20°S: 1° high at 9 pm AUG at 20°S: 15° high at 9 pm SEP at 20°S: 22° high at 9 pm OCT at 20°S: 19° high at 9 pm NOV at 20°S: 6° high at 9 pm DEC at 20°S: -11° high at 9 pm 30°S
JAN at 30°S: -39° high at 9 pm FEB at 30°S: -59° high at 9 pm MAR at 30°S: -72° high at 9 pm APR at 30°S: -64° high at 9 pm MAY at 30°S: -45° high at 9 pm JUN at 30°S: -25° high at 9 pm JUL at 30°S: -7° high at 9 pm AUG at 30°S: 6° high at 9 pm SEP at 30°S: 12° high at 9 pm OCT at 30°S: 9° high at 9 pm NOV at 30°S: -2° high at 9 pm DEC at 30°S: -19° high at 9 pm 40°S
JAN at 40°S: -44° high at 9 pm FEB at 40°S: -65° high at 9 pm MAR at 40°S: -81° high at 9 pm APR at 40°S: -71° high at 9 pm MAY at 40°S: -51° high at 9 pm JUN at 40°S: -31° high at 9 pm JUL at 40°S: -15° high at 9 pm AUG at 40°S: -3° high at 9 pm SEP at 40°S: 2° high at 9 pm OCT at 40°S: -0° high at 9 pm NOV at 40°S: -10° high at 9 pm DEC at 40°S: -25° high at 9 pm
below horizon
low
20-40°
40-60°
overhead-ish
The chart gives its height above the horizon at 9 pm through the year, from 60°N to 40°S. It can be seen from the whole northern hemisphere and south to about 43°S, and never sets north of 43°N.
The distance to NGC 6991 is not well measured
No reliable distance has been measured for it yet.
Objects within 6° of NGC 6991
22 NGC and IC objects lie within 6°. The nearest that are brighter than magnitude 12.5 or have their own page:
NGC 7026, planetary nebula, 2.0° NGC 6997, cluster with nebula, 2.8° IC 1369, open cluster, 2.9° NGC 7000 North America Nebula, H II region, 3.0° IC 5070 Pelican Nebula, H II region, 3.1° NGC 7039, open cluster, 3.3° IC 5067, unclassified object, 3.3° NGC 7048, planetary nebula, 3.5°
NGC 6991 catalog data
Field Value
Constellation Cygnus Designations NGC 6991 Type open cluster Right ascension (J2000) 20h 54.9m Declination (J2000) +47° 28′ Apparent size 23′ Radial velocity -12 km/s Best with Telescope Best month September Catalog page NGC 6501 to 7000
