The Perseus Arm
, which is so conspicuous in the Cassiopeia Window of the autumn Milky Way, is lost to view east of the Perseus Double Cluster, hidden behind the Gould's Belt dust clouds of southern Perseus and northern Taurus.
The Cassiopeia Window extends from just east of the famous variable star Delta ([delta]) Cephei all the way through Cassiopeia to the Perseus Double Cluster, which gives the Perseus Arm
The new data suggest that the Orion Spur, once thought to be merely a hiccup between the Sagittarius and Perseus Arms
(see the July issue's foldout), is more likely a full-fledged branch of the Perseus Arm
But most of the clusters and nebulae in this area lie in the Perseus Arm
, the next spiral arm out from our own.
light of the Double Cluster took flight from the Perseus Arm
Cas OB 6 resides within the Perseus arm
of the Milky Way at a distance of roughly 7,500 light-years.
It lies about 5,900 light-years away in the Perseus Arm
of the Milky Way Galaxy.
Some 20 to 40 million years from now, a million Suns' worth of hydrogen gas will plow into the galactic plane, likely setting off a huge burst of star formation in the Perseus Arm
about a quarter of the way around the galaxy from us.
This refinement gives an indication of the density of the Perseus Arm
compared to the inter-arm regions, and gives hints about the distribution of dark matter in the Milky Way.
They lie 5,000 light-years away on the near side of an interior spur to the Perseus Arm
, the next spiral arm outward.
When you look at these stars you are gazing out to the Perseus Arm
of our galaxy, the next spiral arm out from our Sun's (the Orion Arm).
The team found that while the molecular surface density is 28 times larger within the arm compared to outside it, atomic gas is enhanced only 2.5 times in the Perseus arm
. If small molecular clouds exist outside of spiral arms and are simply melded by density waves, the arm/interarm ratios for atomic and molecular gas would be the same.