α Virginis

Alpha Virginis, or Spica (Latin: spica, ear of grain) is a 1.0 visual magnitude blue giant 262 light years away.

The star represents the ear of wheat Virgo is holding in her left hand, as Virgo was seen throughout antiquity as the Goddess of the Harvest or some similar representation of the fruits of an annual reaping.

Like all zodiacal constellations, the stars of Virgo are found very near the ecliptic, the path of the Sun and all planets. Thus occasionally one will find a planet in the vicinity of its more southern stars.

Locating the star is quite easy as it form a large triangle with two other bright stars, Regulus and Arcturus: Spica. One may also follow the Big Dipper's handle out to Arcturus, then continue about the same apparent distance to Spica.

Place Spica on the extreme eastern rim of your field of view and move west two binocular fields to find M104, the Sombrero Galaxy.

M104 was the last entry in Messier's catalogue, and many observers believe it should have ended there, however the urge to keep adding to his collection proved too great.

In any event, this would have been a magnificent means of capping off an extraordinary collection of Deep Sky Objects: an elegant dark band of stellar dust encircles the galaxy seen edge-on. The galaxy has an apparent visual magnitude of 8.5; small telescopes can glimpse the edge of the galaxy but the larger the instrument the better the view.

Two binaries are in the same field: Struve 1664 and Struve 1682:
     Struve 1664AB: 7.8, 9.2; 224º, 38.0".
     Struve 1682AB: 6.6, 9.7; 297º, 29.3".

From the Sombrero Galaxy move due north two fields: gamma Virginis sits in solitary splendour, encircled by a half dozen or so dim galaxies.

Click on gamma Virginis to continue.


After enjoying the deep sky objects and binaries of the northwestern portion of the constellation, come back to Spica to explore the east.

One and a half binocular fields northeast of Spica are two binaries, 81 Virginis and Struve 1788: binoculars.
     81 Virginis (Struve 1763AB): 7.8, 8.1; 39º, 2.6".
     Struve 1788: 6.7, 7.3; 100º, 3.6" with an orbit of 2613 years.

If you place Struve 1788 on the western edge of your glasses and move northeast one field you'll find iota Virginis.

Iota (Syrma, indicating the train of Virgo's frock) is a bright yellow star in a fairly lonely region; however here one encounters the only globular cluster in Virgo: NGC 5634.
     With an apparent magnitude of 9.5, NGC 5634 requires a medium to large telescope to resolve its many members. A number of blue stragglers are also evident. An eighth-magnitude star is to the southeast, which may be a help or a hindrance. The cluster is about 3.4 billion years old.

About 2º southeast of iota is Struve 1833, identical yellowish-white stars: 7.5, 7.5; 175º, 5.8".


Move slightly to the east, keeping 104 Virginis on the western edge, mu Virginis is near the eastern edge.

Mu Virginis is Rijl al Awwa, ‘the foot of the barking dog’, which refers to a long-forgotten asterism made of beta, gamma, delta, epsilon, and eta and called Al Awwa, The Kennel or The Barker. The star is a main-sequence yellow star twice the size of the Sun, a 3.9 visual magnitude and 61 light years away.

Very near to the southwest, less than a quarter of a degree, lies the pleasant binary Struve 1869: 8.4, 9.5; 131º, 25.9". (Note: this binary is found in neither the WDSC nor the CDSA.)


Finally we visit tau, a notable multiple system–perhaps–with companions which “flock around it like stellar flies” as Jim Kaler describes the scene, although he also points out it might just all be an illusion as some are optical and the others possibly too distant to be gravitationally bound. In any case we list the very wide tauAB:
     tau Virginis (Sh 171)AB: 4.3, 9.4; 287º, 82.7".

In the same field is the pulsating star CU Virginis. An enigmatic star by all accounts, this bright 4.99m star has no Flamsteed number despite being brighter than most of the other Flamsteed numbered stars and doesn't really act like an A class dwarf star. (See Jim Kaler's account for details). It fluctuates from 4.99 to 5.05 every 12h 28m 48.5s. And despite being ignored by the CDSA, CU is also a binary with a dim companion:
     CU Vir (h3343): 5.0, 12.4; 210º, 58.0".

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