Sunday, August 29, 2010

Messier 3 Redo

Sometimes I like to go back and reprocess images to see if I can make them better.  Below is a redo of Messier 3.  The original can be seen here.

Messier 3, in Canis Venatici

Friday, August 27, 2010

Waning Moon

It seems that whenever I decide to image the Moon I do it when it is in a waxing phase. Below is a rare (for me) image of a waning gibbous moon.

The Moon is best imaged when it is in a gibbous or crescent phase. This is because the sunlight is shining across the surface at an angle, which causes objects such as mountains and craters to cast shadows. The shadows help highlight the details of the Moon's surface features.

Click on the image below to see the full-size version. The full-size file is fairly large (about 3.9MB).

Waning Gibbous Moon, August 26, 2010

Messier 103

Open cluster Messier 103 is located in Cassiopeia.  I guess its great claim to fame is the red giant star that appears in the middle of the cluster from our perspective.  I used it to test the alignment of the NJP mount.

Messier 103 in Cassiopeia

Jupiter and Moons

This composite image of Jupiter and the Galilean moons was created using the Epsilon-200 astrograph.  I had just finished imaging the moon and, on a whim, decided to see if the scope had enough magnification to pick up any details.  Surprisingly, it did.  It's nothing spectacular, but I thought it was kinda interesting.

Jupiter and Galilean Moons

Monday, August 23, 2010

The Coathanger

The Coathanger is an asterism in Vulpecula. Cataloged as Collinder 399, and also known as Brocchi's Cluster, it was thought to be an open cluster until fairly recently. This image was a test to see if I could fit the entire cluster onto my DSLR's CMOS chip using the Epsilon-200. I will go back and take longer exposures when I get a chance.

Coathanger Cluster, Epsilon-200
Here is an earlier image taken afocally with my ST80:

Coathanger Cluster, ST80

Sunday, August 22, 2010

Helix Nebula

I took this image of NGC 7293, the Helix Nebula, the same night that I imaged the Cocoon Nebula.  It was way hotter that night than it needed to be, and my DSLR was showing definite signs of heatstroke.  Still, I plowed forward, taking images on the Epsilon-200.  The NJP mount was giving me fits, too, but I managed to make it behave enough to get a few decent subs of the nebula.  Anyway, after many attempts at processing and reprocessing what, for all intents and purposes, was a whole bunch of crummy subs, I got this:

NGC 7293, the Helix Nebula

Messier 92

Messier 92 is a globular cluster in Hercules. It doesn't get as much attention as its brighter sibling, Messier 13. In fact, M13 has pretty much gotten all of the glory. After all, M13 is often referred to as the "Great Globular Cluster in Hercules," and the "Hercules Cluster." So where does that leave M92? Is it the "Not so Great Globular Cluster in Hercules?" The "Also Hercules Cluster?" Or, the "Red-headed Stepchild Cluster in Hercules?"

In my opinion, M92 is worth a look. It has a very bright center, and it is said that the cluster is visible to the naked eye in dark skies. I haven't seen it naked-eye, yet.

Messier 92 in Hercules

Saturday, August 21, 2010

Cocoon Nebula - Redo

I went back and reprocessed the Cocoon Nebula image from a few days ago. It looks a little better to me now. I'm not 100% satisfied with it, though. One thing I like about this version is that the colors of the surrounding stars are more pronounced.

IC 5146 (Cocoon Nebula) and Barnard 168


Moonrise, August 21, 2010

Thursday, August 19, 2010


This is a sundog that appeared in our sky on August 8, 2010.  Sundogs are created by ice crystals in the atmosphere.  Even in warm climates, like ours, they can appear in high clouds.  The sun is out of frame to the right.

Tuesday, August 17, 2010

Cocoon Nebula

The Cocoon Nebula (IC 5146, also Caldwell 19) is located in the constellation Cygnus.  Dark nebula Barnard 168 extends from the Cocoon Nebula to the edge of this image.

Heat is one of the worst enemies of imaging chips.  I do not have a rig to keep my DSLR cooled down, and it was VERY hot the night that I imaged the Cocoon Nebula.  There was a significant amount of noise in each of the subs.  I removed a lot of the noise, but I think that the overall image quality suffered pretty terribly.

IC 5146 (Cocoon Nebula) and Barnard 168

Saturday, August 14, 2010

A Plethora of Planetaries

It is probably fair to say that when most stars die, they do it in style.  The bigger ones explode, leaving behind either black holes or extremely dense cores.  Some stars blast out shells of gas into interstellar space near the end of their lives.  The gas is illuminated by the star, and can take on a variety of shapes and colors.  These clouds of gas are called planetary nebulae.  They are called "planetary" because some resemble large planets.

Planetary nebulae are believed to only last a few thousand years, which is a short period of time when compared to the billions of years that their parent stars may have lived.  The Sun is expected to produce a planetary nebula toward the end of its life.

Below is my collection of planetary nebulae.  Some were primary targets, but others were simply in the field of view of another object.  I found a few of them by accident.

Charles Messier cataloged four planetary nebulae.  Each is visible as gray patches in small telescopes:

Messier 57, the Ring Nebula, in Lyra
Messier 76, the Little Dumbbell Nebula, in Perseus
The Little Dumbbell's big brother can be seen here.

Messier 97, the Owl Nebula, in Ursa Major
NGC 2438 is located in the constellation Puppis.  It is on the line of sight between us and Messier 46:

NGC 2438 in Puppis
I ran across several tiny planetary nebulae while examining my image of Messier 7.  The nebulae are the blue dots at the center of each image:

PK 355-4.1
PK 356-4.1
PK 356-5.1
Each of the above nebulae are in the Perek-Kohoutek catalog.  The numbers refer to their galactic coordinates.

NGC 7662, the Blue Snowball, is a popular target for amateur astronomers.  It is small, but intensely blue to the naked eye.  Here is an image that is composed of several short exposures:

NGC 7662, the Blue Snowball, in Andromeda

I ran across another planetary nebula while processing my image of Messier 34.  I got really excited because I couldn't find any references to it.  Was I the first to discover it?  "Surely not," I reasoned.  But amateur astronomers make new discoveries from time to time.  Finally, after quite a bit of searching on the Net, I found that it had already, in fact, been catalog by George Ogden Abell.  Here is planetary nebula Abell 4 in all of its not-discovered-by-Rory glory:

Abell 4 in Perseus

Thursday, August 12, 2010

Moon and Planetary Conjunction

The Moon, Mercury, Venus, Mars and Saturn were grouped together tonight just after sunset.  Mercury was too low on the horizon for me to see, though.

August 12, 2010 Moon, Venus, Mars, Saturn Conjunction

Sunday, August 8, 2010

Messier 24, the Sagittarius Star Cloud

Messier 24 is a region of the Sagittarius Arm that is relatively free of the obscuring dust that normally blocks our view of the plane of the Milky Way.  It gives us a glimpse of the densely populated region near the center of the galaxy.  A few objects of note within Messier 24 are open cluster NGC 6603, and two dark nebulae cataloged by E. E. Barnard.

Messier 24, the Sagittarius Star Cloud; E-200; 20x120
Messier 24 with Labels

Globular Clusters

Globular clusters are dense groups of stars that orbit large galaxies, such as the Milky Way.  Studies indicate that the stars found in these clusters are very old.  There are over 150 known globular clusters orbiting our galaxy, and there may be as many as 180 to 200 total.

Most globular globular clusters are only 100 to 200 light years across, and may contain anywhere from 10,000 to a million stars. The stars are held within the cluster by their mutual gravity.  The density of stars per cubic area of space is very high, with as many as 100 to 1,000 stars per cubic parsec at the core!

The term "globular" comes from the Latin word, globulus, which describes the spherical shape of the clusters.

Several globular clusters are within the reach of amateur telescopes, and a few are even visible to the naked eye.  Charles Messier cataloged several of them.  I have imaged a few.  Due to various issues with the NJP mount, though, I do not consider all of my attempts successful.  Here, though, are the ones that I've kept:

Messier 3, in Canis Venatici; E-200; 52x15
Messier 13 and galaxy NGC 62 in Hercules; E-200; 7x120
Messier 22 in Sagittarius; E-200; 18x120

Saturday, August 7, 2010

Image Redo!

I've finished replacing the astroimage JPEGs with PNGs.  The images look like they're supposed to now.  From here on out I will use PNGs for astroimages (JPEGs for everything else, probably), so be aware that some of the files can be quite large.

Friday, August 6, 2010

Test Post

This is a test post to see how Blogger handles PNGs.  It appears to compress JPEGs, which degrades the image quality.

M45 - JPEG

M45 - PNG
Well, it appears that I need to go the PNG route, which means that I will need to go back and replace all of the JPEGs on the blog with PNGs.  I'll do that later.  It's time for bed!

A Cluster of Open Clusters

This is post lists the rest of the open cluster images that I have made, but have not yet posted.

Here is Messier 7, also known as Ptolemy's Cluster. It is visible to the naked eye as a fuzzy patch near the end of the tail of Scorpius.  From our perspective, the cluster is superimposed on the Sagittarius Arm of the Milky Way.

Messier 7 (Ptolemy's Cluster) in Scorpius
Messier 34 is a relatively small open cluster in Perseus:

Messier 34 in Perseus
Messier 37 is located in Auriga, fairly close (from our point of view) to Messier 36 and Messier 38:

Messier 37 in Auriga
Messier 44 is visible to the naked eye as a fuzzy patch in the constellation Cancer. It is sometimes called the Beehive Cluster, but the ancient Romans and Greeks knew it as Praesepe (Latin for "manger").

Messier 44 in Cancer
Messier 45, more commonly known as the Pleiades, is probably the best known open cluster. It is a relatively young cluster of about 500 stars in the constellation Taurus. Several of the stars illuminate a molecular cloud that is currently passing through the vicinity of the Pleiades. This cloud is not related to the cloud from which the stars formed.

Messier 45 (the Pleiades) in Taurus
I posted an image of Messier 46 in the previous post, but this one is a close-up. Planetary nebula NGC 2438 is clearly visible here:

Messier 46 in Puppis
Messier 52 is located in Cassiopeia. Other interesting features in this area include the Bubble Nebula and an open cluster catalog as Czernik 42. The "bubble" in the Bubble Nebula was formed by a star whose stellar winds are pushing out on the material in the surrounding nebula. Czernik 42 is a fairly inconspicuous cluster, located just below and to the left of the reddish stars that are below Messier 52 in this image:

Messier 52 in Cassiopeia
And, finally, here is Messier 93. It doesn't get a lot of press. I guess that's because it lacks the glitz of more interesting deep sky objects. Still, I think it has some things going for it that make it a worthy target. For one, it is located along the plane of the Milky Way galaxy from our perspective, so there are a lot of stars to see besides those in the cluster. Also, it has an interesting shape--most describe it as an arrowhead, but I keep thinking "mouse pointer." The SEDS Messier Pages describe it as a "nice open star cluster." I guess that means that it has a pleasant disposition.

This image was taken with my ST80 on the EQ-1 mount:

Messier 93 in Puppis

More Double Clusters

Open clusters (also called galactic clusters) are groups of stars that formed from the same cloud of gas and dust. Over time, gravitational interactions among cluster stars spread them throughout the galactic neighborhood. Open clusters are mostly composed of young, bright stars. It is believed that the Sun formed in an open cluster that dispersed long ago.

Sometimes open clusters appear in pairs or groups in our sky. The Double Cluster in Perseus is the most famous of these, partly because the two clusters are actually close to one another in space. Other groupings are simply chance alignments, with one cluster being significantly further than the other.

One such grouping is Messier 35 and NGC 2158 in Gemini. NGC 2158 was once thought to be a globular cluster, which is actually sort of satellite galaxy that orbits large galaxies like our own. It was eventually determined to be an unusually dense open cluster located much further away than Messier 35.

Messier 35 (left) and NGC 2158 (right) in Gemini
The constellation Auriga contains several bright open clusters and many smaller ones. Messier 38 and NGC 1907 make a nice double:

Messier 38 (left) and NGC 1907 (right) in Auriga
Here is a wider-angle shot of the area around Messier 38 that also includes Messier 36 and two nebulae:

Messier 38 (upper-right) and Messier 36 (lower-left)

Another interesting pair is Messier 46 and Messier 47 in Puppis. Planetary nebula NGC 2438 appears to be part of Messier 46, but in reality it is between us and the cluster. The image below also contains two smaller open clusters cataloged as NGC 2423 and NGC 2425 (see the labeled image, further down).

Messier 46 (left) and Messier 47 (right)
I call the image above my Open Cluster Family Portrait.  Messier 46 is the mother (she's wearing a pretty planetary nebula as jewelry), Messier 47 is the father, and the two other clusters are the children.  Here is a labeled version:

Open Cluster Family Portrait with Labels

Thursday, August 5, 2010


Got a small telescope?  Try Albireo!  Yes, folks, Albireo is the star for you!  You get not one, but TWO stars for the price of one!  That's a golden-yellow class K star with a blue-green class B star!

But wait!  There's more!  Call within the next 20 seconds and we'll make that K star a spectroscopic binary*!  That's THREE stars for the price of one!

This item is only available in the constellation Cygnus.  Order today!

Albireo (Beta Cygni)
*Spectroscopic binary requires perfect seeing conditions and a telescope with at least a 20-inch aperture.  Knowledge of speckle imaging may be required.

Colorful Moon

What color is the Moon?

To the naked eye it appears as shades of gray, but, there are subtle color variations across its surface.

The Moon's colors are a good indicator of its mineral composition.  The blue and orange areas are basalt.  The blue areas have a higher concentration of titanium.  Color variations in and around craters give clues to the minerals that are present below the surface.

Early astronomers mistook the large, dark areas on the Moon's surface as bodies of water.  Johannes Kepler named them maria, which is Latin for "seas."  They are actually lava plains that formed during the Moon's volcanic past.

The lighter areas are the highlands, named terrae (earth) by Kepler.  The highlands are heavily cratered, and are older than the maria.

Color-Enhanced Moon; E-200; May 22, 2010
Here is the original image:

Wednesday, August 4, 2010

Trifid Nebula

This is the Trifid Nebula (Messier 20), located in Sagittarius. I really like the contrast between the red and blue.The red color comes from gas that is ionized by the stars within the nebula. (This ionization effect is basically the same effect that makes neon and fluorescent lights glow.) The blue is from light that is being reflected off of gas and dust. Trifid means "divided into three lobes," which refers to the dark dust lanes that divide the red portion of the nebula.

Open cluster Messier 21 is on the left in this image:

Messier 20 and Messier 21, E-200, 11x120
Val Ricks and I each imaged the Trifid Nebula at about the same time, so we decided to combine our image data into a single image. Below is my version of the result. Note the diffraction spikes on the star in the lower-left!
Trifid Nebula Collaboration