Amazing Space

315 Pages·2016·44.4 MB·English

by  Gerry Marrs

AMAZING
SPACE
Breathtaking Rare Photos of Celestial Miracles

Edited by Gerry Marrs
© 2016 Gerry Marrs
Cover design by Gerry Marrs, Twin Jet Nebula
All photos have been enhanced and altered for use in this textbook.
First edition, 2016
ISBN-13: 978-1539828808
ISBN-10: 1539828808

2.
Part 1 – Nebula

What is a nebula? Some of you might think of one in terms of a lighted cloud in
space, creating beautiful illusions that accents the stars behind it. You might be
basing your beliefs about certain science fiction movies where these gas
disturbances can wreak havoc on subspace communications and various
sensors on board the spacecraft. Regardless of what your preconceived notions
about nebula actually are, one fact is certain. No one living, as of yet, has
actually been up close to one to relay their experiences. That is left up to distant
observation from afar and years of research experience regarding the known
universe and physics.

A nebula is comprised of interstellar dust, hydrogen, helium and several ionized
gases. Most nebulae are of vast size, even up to millions of light years in
diameter. While it was imagined by the public that nebula consisted of a thick
cloud of active electromagnetic activity, in reality, if one were close enough to
actually touch the material, it would only be a slightly glowing mass of gaseous
material that would be barely visible. They glow only because of their
embedded stars illuminating their wondrous expanse from within.

Some of these nebula (or plural, nebulae) are clustered in regions of space
where brand new stars are being formed. In other cases, nebulae are the results
of a dead star. You will see some incredible pictures and examples of a nebula
in the next several pages and all were photographed and measured by NASA
special instruments.

3.
Several different types of nebula have been categorized.

Planetary nebula is typically an expanding shell of ionized gas emitted from
dying red giant stars. They received their name as a result of astronomer William
Herschel (1738 – 1822) believing that they were planets due to their round shape
when viewed through a telescope.

Globular Clusters

These consist mainly of old stars. Globular clusters aren't focused in the plane of
the galaxy but rather, are randomly distributed through the halo. There are
several hundred globular clusters associated with our own galaxy. A normal
globular cluster is a few hundred light-years across.

Open Clusters

Open clusters are loose aggregations of hundreds or dozens of young stars. They
can are usually not bound and will disperse in a relatively brief period of time.
They may be often associated with more diffuse nebulae. Additionally, these are
sometimes called "galactic clusters" because they may be normally present in
the plane of a galaxy. A typical open cluster is less than 50 light years across.

4.
Emission Nebulae

Emission nebulae are clouds of high temperature gas. Emission nebulae are
often the sites of on-going star formations.

Reflection Nebulae

Reflection nebulae are clouds of dust which are merely reflecting the light of a
nearby star or stars. Reflection nebulae are also generally sites of star formation.
They are generally blue because the scattering is more efficient for blue light.
Emission nebulae and reflection nebulae in many cases are seen together and
are occasionally both called diffuse nebulae.

Dark Nebulae

Dark nebulae are clouds of dust which are just blocking the light from whatever
is behind. They are physically much the same to reflection nebulae; they appear
different only due to the geometry of the light source, the cloud and the Earth.
Dark nebulae can also be frequently seen in conjunction with reflection and
emission nebulae. A typical diffuse nebula is a few hundred light years across.

Supernova Remnants

Supernovae occur when a massive star ends its life within an amazing blaze of
glory. For a few days, a supernova emits as much energy as a whole galaxy. A
large fraction of the star is blown into space as a supernova remnant when it is
all over. A typical supernova remnant is a few light years across.

5.
The next section details the breath-taking images captured by such famous
space telescopes as Hubble and the Spitzer Telescope.

6.
7.
PLATE 1: The Twin Jet Nebula, or PN M2-9, is a striking example of a
bipolar planetary nebula. Bipolar planetary nebulae are formed
when the central object is not a single star, but a binary system,
Studies have shown that the nebula’s size increases with time, and
measurements of this rate of increase suggest that the stellar
outburst that formed the lobes occurred just 1200 years ago.

8.
9.
PLATE 2: The Dumbbell nebula, also known as Messier 27, pumps out
infrared light in this image from NASA Spitzer Space Telescope.
Planetary nebulae are now known to be the remains of stars that
once looked a lot like our sun.