The last phase of a given star
To look and to
observe are synonyms of actions, but when it comes to Astronomy they are not
the same matter. Observing is more than just simply looking at something, but trying
to understand what that something is and how amazing it is to be able to see
it. People less involved with astronomy would consider the views from my
binocular as something boring and repetitive because many objects seem to look
the same: fuzzes and faints spots in the sky. Yet it is those white-grayish spots of light that
make my stargazing sessions the most exciting adventures in the night.
Looking at
galaxies, nebulas or stars that are thousands or millions of light years from
us is an indescribable experience, no matter how they look in the eyepiece. Of
course getting more visual detail is even more exciting, but knowing what they
are, how big they should be or how far away they are and seeing them with your
own eyes in a live view is a priceless experience that should be done at least
once in a lifetime.
Planetary
Nebulas were a new thing for me, until I could see this, my first one, I honestly
did not expect to be able to see one of them through my binoculars, but a clear
and truly dark sky gave me that access.
Wherever there is a star or at least a main sequence star like our sun, it could be a planetary nebula eventually in time. After having spent their primary fuel, hydrogen and start to burn Helium instead, a main sequence star becomes a red giant star because several physical changes in the nucleus. Sometime later (speaking in thousands or millions of years) the star begins to use heavier elements to get energy such as oxygen and carbon and it experiences violent changes in temperature, pressure and gravity causing the ejection of the outer layers of the star while the core becomes a large mass compacted nucleus: a white dwarf. This stellar spectacle is known as planetary nebulae. There is nothing involving planets in this matter, it is simply a “misnamed object” coming from the German astronomer William Herschel, who compared this phenomenal view with the images provided at the time of the gas giants in our own solar system.
M27 was the
first planetary Nebula to be discovered by Charles Messier in 1764. It seemed in
the binoculars as if it was a dense circle which was cut by two parallel and opposite
segments. Those segments, better seen with averted vision, apparently complete
the circular shape but they seemed dim and fuzzy so it was difficult to see the
edges of the nebular zone. The core
itself seemed brighter and denser than an average globular cluster and the
edges of the core were well defined. In most of the photos pictured on the web
it is possible to see two big lobules around the tiny white star showing the
color of the excited particles by the radiation of the dying star.
Watching this
dying star was an amazing experience, to know that not only could I look into a
global cluster and see the birthplace of stars, but look into a planetary
nebulae and see the end of this ball of fire’s life.
Once again, I
wish you clear and dark skies!
LG
Edited by: Jennifer Steinberg (editor in chief)
Sources:
Stellarium
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