If we look to this portion of the constellation Cepheus with a
telescope, we can hardly notice anything but a lot of stars, because
the field of view lies within the plane of our Galaxy. But patient
integration of light during long exposures shows us faint details in
both dark and light nebulae.
The dark Cave Nebula in the upper-left corner is
surrounded by Sharpless (Sh) 155 nebula, glowing in the deep-red color
of hydrogen H-alpha spectral line, stimulated by light of young and
hot stars. Other nebulae appear as black, covering light of background
stars or they are reflecting blue light of nearby stars, like the VDB
155 close to image center.
A small bright blob in the lower left portion of the image is a
Herbig-Haro object (HH) 168. HH objects mark locations, where a star
is born, still surrounded by a nebulosity, already shaped into
rotating disk. Such remnants of the material, from which the star was
created, block the light of the new-born star and the pressure can be
released only through the disk poles. Jets of material, escaping from
the northern and southern poles, reveal a place where a star was born
and are typical for HH objects.
Image was acquired with G2-8300 camera on the FSQ106ED telescope. Total
exposure time exceeds 12 hours. More detail are available on the