Particulars:
General:
Just north of Sagitta and Delphinus and south of
Cygnus this constellation is located between DECL=+30
degrees and DECL=+20 degrees and RA=19h and RA=21h 30m. Although Vulpecula
is not a very bright constellation it is an interesting one.
According to The night sky (Ian Ridpath) this
constellation was originally known as Vulpecula cum Anser:
the Fox and the Goose.
Stars and other objects
The double star alpha Vul is a red giant
(spectraltype M0III) with a brightness of 4.44 mag. Binoculars
reveal an unrelated 6th mag companion, 8 Vul.
A very interesting group of stars is the Coathanger:
six stars of 6th and 7th mag are lined up building a nearly
perfekt row. From the center of this line four stars form a hook
completing the shape of a coathanger. This remarkable star
cluster is close to the border of Sagitta (about
DECL=+20 degrees and RA=19h 30m).
The planetary nebula M 27 was the first ever
discovered (by Charles Messier in 1764) and is certainly the most
impressive in the sky. It can be observed with binoculars. It
appears as a dim green glowing disk with an extension of a
quarter of the diameter of the full moon. Large telescopes and
photographs show a double-lobed shape.
Another type of stellar object was first discovered in this
constellation: pulsars. In 1967 astronomers (Antony Hewish and
Jocelyn Bell) in Cambridge discovered completely regular signals
from a certain direction of space. Hewish and Bell were not
looking for pulsars but were interested in scintillation of radio
signals of quasars. During their survey they found an anomaly
which finally turned out to be the signals of an fast rotating
neutron star. The pulses came 8and still come) every 1.3373
seconds - to regular to be associated with any other object. This
new object was called CP 19191 for Cambridge
Pulsar near alpha=19h 19m. Nowadays its called PSR
1919+21 (PulSaR at RA=19h 19m and DECL=+21 degrees).