Vulpecula the Little Fox

The Italians called this group Volpe colla Oca, the Germans Fuchs and also Füchschen, mit der Gans while the French saw it as Petit Renard avec l'Oie.

There is no proper named star in this constellation except perhaps alpha, which in times past may have been referred to as Anser, Lukida, Lucida or Anseris. Alpha is a magnitude 4.4 red M-type giant star and the only star bright enough to receive a Greek letter. Alpha lies at 297 (± 18) light years and has a luminosity of 115 (± 14) Suns. It is a member of the Arcturus group of stars that share the same proper motion across the sky.

There is a wide optical companion, 8 Vulpeculae, first noted by F.G.W. Struve in the early 1800's. This magnitude 5.8 K-type orange giant only appears to share the same neighbourhood as alpha. In reality, it lies 484 (± 45) light years away, shining with the light of 86 (± 16) Suns.

There are a further 9 stars above 5th magnitude, none deserving of a Greek letter, relegated to the catalogue of Flamsteed. The next brightest star in Vulpecula is 13 Vulpeculae, 5.7° east and slightly south of alpha. Shining at magnitude 4.6, this B9.5 white giant (or perhaps A0) is a close double. The computed distance is 359 (± 26) light years and the combined luminosity 150 (± 22).

With a separation of only 1".1, measured in 1987, and components of magnitude 4.7 and 7.4, resolution may be difficult in all but larger telescopes. Remember, this constellation lies low in the northern sky and the star itself reaches only 29° in altitude above the horizon at culmination. Therefore, try this one around mid-September.

The open cluster NGC 6800 lies 0.5° northwest of alpha. Around 50 stars of mag. 10 or so live here and larger apertures may resolve a number of fainter members.

Around 17'.0 to the east of 6.3 mag. 7 Vul. lies an elongated cluster, NGC 6802, the brightest star at magnitude 14.0. A 25cm or larger aperture is needed to resolve this group. One of the older open clusters to inhabit the Milky Way's spiral arms at 1.6 billion years, it will need a dark sky to see well.

A better use of your time would be to move 1.2° to the west and capture Collinder 399, a 1° diameter group of 40 bright stars, loosely scattered across the field. The brightest star, 4 Vul., is a K0 giant and shines at magnitude 5.1. It lies at 236.7 (± 10.0) light years and the luminosity is 38.5 (± 3.2). Another member is 5 Vul., a magnitude 5.6 A-type main sequence star with a luminosity of 21.4 (± 1.6) Suns. These two stars and the surrounding family of bright suns are known to the northern hemisphere observers as Brocchi's Cluster.

Just south of 19 Vul. lie two open clusters, NGC 6882 and NGC 6885. The former is a rather poor, small group seemingly connected to the latter by a chain of stars. NGC 6885 is far larger and more impressive and contains as its member 20 Vul. This B7 main sequence star lies at 1140 (± 170) light years and the computed luminosity is 440 (± 130) Suns.

The superb open cluster NGC 6940 lies around 5.5° east and slightly north of the above clusters. This is a rich and bright group, born from a dark molecular cloud over 1 billion years ago, but now putting on a show that needs a wide eye-piece field to contain it. An orange-red star FG Vulpeculae appears to lie amongst it, a semi-regular long period variable star of spectral type M5 II.

There are two planetary nebulae worth hunting down. Planetary nebulae are the death throes of stars, where an elderly sun blows off a large proportion of its mass into interstellar space, leaving behind an intensely hot and energetic core. Planetary nebulae are so called because Sir William Herschel likened them in size and shape to the disks of planets in 1785. However Darquier, when discovering M57 4 years earlier, thought of it as "...looking like a fading planet." A good number of planetary nebulae do show a disk or ring structure but they come in other forms as well.

NGC 6842 lies near the northern border with Cygnus, the Swan. It appears as a large and faint round haze of low surface brightness so needs a dark sky and the larger the aperture the better.

The best object in Vulpecula and one of the best of its type in the heavens is M27 (NGC 6853), the Dumbbell Nebula. Discovered by Messier on July 12, 1764, it has fascinated astronomers ever since. He recorded it as a:

" Nebula without star. Seen well in 3½ foot telescope. Appears oval and contains no star. Recorded on chart of comet of 1779. ReviewedJan. 31st, 1781. (Diam. 4')."

Sir William Herschel, in 1785, mistakingly imagined it as a large group of unresolved stars, writing that:

" Though its appearance is not large, it is probably a double stratum of stars of a very great extent, one end of which is turned towards us. That it is thus situated may be surmised from its containing, in different parts, nearly all the three nebulosities; viz. the resolvable, the coloured but irresolvable and a tincture of the milky kind."

Admiral Smyth added:

" This magnificent and singular object is situated in a crowded vicinity where field after field is very rich. M27 is truly one of those splendid enigmas which, according to Ricciolus, are proposed by God but never to be subject to human solution. The axis of symmetry is not less than 5'. P.A. of axis 032 degrees."

Visually, M27 is an impressive sight, presenting an hour glass or butterfly shape in amateur telescopes. It can be found 23'.9 south of 14 Vulpeculae, within a C-shaped asterism of bright stars. M27 has a high surface brightness so can be seen in small telescopes, though it appears more dramatic in larger apertures.