SELF

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S.B. Karavashkin and O.N. Karavashkina

To present this kind of galaxies more completely, we have put here one more non-compact galaxy, NGC 4414 (see Fig. 25).

a

b

Fig. 25. The non-compact spiral galaxy NGC 4414: (a) - positive image, (b) - negative. The image has been copied at  http://heritage.stsci.edu/1999/25/caption.html

The authors of this image describe it so: "The resulting distance to NGC 4414, 19.1 Megaparsecs or about 60 million light-years… Due to the large size of the galaxy compared to the WFPC2 detectors, only half of the galaxy observed was visible in the datasets collected by the Key Project astronomers in 1995. In 1999, the Hubble Heritage Team revisited NGC 4414 and completed its portrait by observing the other half with the same filters as were used in 1995. The end result is a stunning full-color look at the entire dusty spiral galaxy. The new Hubble picture shows that the central regions of this galaxy, as is typical of most spirals, contain primarily older, yellow and red stars. The outer spiral arms are considerably bluer due to ongoing formation of young, blue stars, the brightest of which can be seen individually at the high resolution provided by the Hubble camera. The arms are also very rich in clouds of interstellar dust, seen as dark patches and streaks silhouetted against the starlight" [23].

Just as in the previous image of NGC 3314, we see in NGC 4414 the clusters of primary stars insensibly shading into three arms under formation, and this peculiar nucleus is surrounded by the disk of interstellar dust. But the spiral arms have been formed not finally, and with small angular velocity of this galaxy we can expect this process to be quite long.