March 29, 2009

Palomar 4 Final

Palomar 4 is the Milky Way's second most distant globular cluster (the other is 10% further out, see here). It is 356,000 light years from the Sun and 364,000 light years from the center of the galaxy. For some perspective as to how far out that is, consider that the galaxy itself is only about 100,000 light years across. That means Palomar 4 is 3.5 times further from the Milky Way's center than the galaxy is wide. If the Milky Way is a frisbee ten inches wide, Palomar 4 is three feet away from its center! There are several other galaxies closer to the Milky Way than that.

At this great distance, only very bright stars show up as stars. Compare my results with this image taken from the Sloan Digital Sky Survey.
These are the brightest stars in the cluster. Many more have been detected individually by professional astronomers that are much dimmer, down to magnitude 25 or 26. These stars in my image are further than any individual stars I have imaged before now. They are very dim. I could never see them with my eyes through the telescopes I have, but the camera catches much dimmer objects than my eyes ever could. Here is my image with magnitudes of the brighter stars filled in (mags provided by Please click on the image for a readable view.
Palomar 4 is something someone with a really large telescope (i.e., 20") might try to see (as here). I feel fortunate that I can catch it from my backyard in my little 5.3" scope.

This image is 87 minutes worth of 20" exposures taken with the Atik 16 through the Vixen R135S, unguided, processed in Nebulosity, Registax, and PSE7.

Update: NHAC member and accomplished astrophotographer Paul Downing also recently shot Palomar 4. I'm honored to show his image here at Polaris B:
As you can see, Paul's image is as deep as the survey. And it has greater resolution than mine, and color. This image begins to show Palomar 4 as the globular that it is. Great! The image was taken with a Celestron C14 at f/7 on a Takahashi NJP. It is an L:R:G:B combination using an SBIG ST10-XME CCD camera - 4x5min exposures of each component, dark subtracted and stacked in MaxIm CCD and color combined in Photoshop. It was taken in southern Spain at 36d 51m 41s N; 3d 15m 28s W. More of Paul's work can be seen at

Anyone else?

NGC 2903

Here is another shot of NGC 2903. I keep returning to this galaxy because of its dramatic appearance. It's a beauty, isn't it? This shot is not too much of an improvement over my earlier image (see also here), but I was practicing while I waited for Palomar 4 to climb closer to the meridian. This is only about 25 minutes of 20" exposures.

NGC 4361

Here is a planetary nebula in Corvus that I have never seen with my eyes. I have never tried to see it from a dark sky site, but only from my back yard. I always wondered what it looked like. This is what it looks like. This image is 30 x 20" with the Atik 16 through the Vixen R135S, unguided, processed in Nebulosity, Registax, and PSE7.

March 28, 2009

Palomar 4 Prelim

This is a preliminary of tonight's work. See that rather faint group of stars in the middle of the image? It is called Palomar 4. Palomar 4 is over 350,000 light years away. It is a far-flung globular cluster gravitationally attached to our galaxy but over three times the galaxy's length away from it. Essentially, it is floating out in space by itself. The final image will be much better than this, but I am pretty excited just to know I caught it!

March 22, 2009

Venus Last Night

This frame was taken with the same equipment as this frame on March 1st. See what three weeks will do to the size of the planet as it orbits further toward the earth? Venus will soon be as close as it ever comes to the earth, so its crescent appears much larger now than it was just a few weeks ago. Notice also that the crescent is thinner now than then. We are seeing more of the back of the planet as it moves between us and the sun.

Saturn, Izar

Saturn was great tonight. The rings are almost on edge. With the 100 f/6 achromat at 120x, I could see the slim shadow of the rings across the planet and three moons in orbit. Seeing was pretty good, and I was able to kick up to 240x. That's a lot for the 100mm scope, but it handled it well. The shadow was bolder at the higher magnification, and the moons more obvious when seeing cooperated. The rings are obviously not exactly on edge now, and this was more obvious at 240x. It's a nice view, though.
After looking at Saturn, I swung the scope around to Epsilon Bootes, also called Izar. Izar is a double, and tonight it was cleanly split at 240x. That's one I did not think I would coax out of my little achromat. This was a lot of fun.

March 19, 2009


Early this morning, around 12:30 am, I took a peak at Saturn through the AR6. Five moons were on one side, like beads dripping off the rings---a very nice sight. I could also see cloud bands on the planet. The rings themselves were not uniform in color, but they appear so narrow now that I did not recognize any features.

March 3, 2009

Luna in the AR6 (3-3-2009) --- The "Lunar X"

This is not a bad image considering the high clouds and haze through which it was shot. It is a single exposure with the XTi through the AR6 at prime focus. The upper image has been processed further in PSE7. The upper image includes the famous "Lunar X" described here and here.

March 1, 2009

Venus in Broad Daylight

Venus was easy to see today during the day. I took these shots about 3 pm with the XTi and the Nikon 300mm f/4.