Abbreviation:
Aql
English name:
Eagle
Coordinates
see Stellar data
Particulars:
Cepheid eta Aql (period: 7.2 days)
Binaries 15 Aql, 57 Aql, pi Aql
Planetary Nebula NGC 6891, NGC 6803
Open star cluster NGC 6755
Meteor Showers: June Aquilids, Epsilon Aquilids
General:
A pretty constellation at the celestial equator; it lies (roughly spoken) between DECL=+10 and DECL=-10, RA=19h and RA=20h 30m. The alpha star Altair (arab.: the flying eagle) forms with alpha Cyg and alpha Lyr the so called Summer Triangle.
See here how the stars form the eagle.
Due to the Rift, a lane of obsuring dust, the Milky Way splits into two through this constellation and Ophiuchus. Many rich star fields can be observed in this area.
Stars and other objects
The variable star eta Aql is one of the brightest Cepheids; its brightness varies from 4.1 mag to 5.3 mag every 7.2 days.
The double 15 Aql is a yellow 5th mag star accompanied by a 7th mag star. It can easily be observed with small telescopes.
Another easy pair for small telescopes is 57 Aql, constisting of two 6th mag stars.
For telescope with an aperture of at least 100 mm pi Aql is an interesting object. The planetary nebula NGC 6803 shows a small but bright ring.
Viewing NGC 6891 reveals a bright disk with a faint ring, which is about 15'' in diameter.
Only three radar studies give hints to the existence of the June Aquilids. It look like the meteors are falling from June 2nd to July 2nd, with an hourly rate between 13 and 35.
To see the meteor shower of the Epsilon Aquilids some additional optical help seems to be necessary. As far as the sources say, the shower is taking place Mid-May. See Gary Kronk's database for detailed information.
Mythological Background:
Aquila, the eagle, is one of the the two birds (Cygnus, the swan, is the second), which are hunted by Hercules. Yet it seems that the two birds were lucky and have escaped. It is assumed that these birds (together with a third one, the Vulture - nowadays the constellation Lyra) represent the Stymphalian Birds - one of the tasks of Hercules. |
