Wednesday, October 31, 2012

31Oct2012 Lunar Imaging Session

Last night, I attempted to do some photo-stitching with the lunar images I got using eyepiece projection. This is the process wherein you put together detailed images of particular areas with a smaller field of view to form one big image.

I also labeled some of the lunar features in some of the shots

Friday, October 26, 2012

Astroart - Chibi Astronomers

Just for fun. I doodled some chibi version of me and my batchmates in the MS Astronomy degree program. Here we are carrying our respective telescopes. From the left, you have Lieza with a Meade ETX90, Pamela with an Astromaster70, Vanessa with an Astromaster130, and me with a Sky-Watcher Explorer 150PL. :)

October 26, 2012 Moon

Last night's sky was pretty cloudy but the brightness of the Waxing Gibbous Moon was able to peer out a couple of times from its clouded veil.

Wednesday, October 24, 2012

Orionids and Telescopes

Last Monday (22 Oct 2012) the RTU Astronomical Society held an overnight observation setting to train the 1st year students in the use of the telescopes as well as to catch a glimpse of the Orionids activity. For me it was an opportunity to observe the sky from RTU using the department's different telescopes.

While the lectures were being conducted upstairs, I stayed in the quadrangle with some students to observe the moon and several deep-sky targets that were visible despite the urban skylight. Among the deep-sky targets we observed were: M57(Ring Nebula); M31(Andromeda Galaxy); M29(Open Cluster) and Albireio(Double Star); NGC 884 & 869(Double Cluster); M45(Pleiades Open Cluster); M41(Open Cluster); the famous M42(Orion Nebula); as well as several other open clusters.

As soon as the lectures were over, the students came down with the rest of the telescopes to practice assembly and alignment. This gave the first year students a chance to operate the telescopes on their own. After they were graded, they were left with some time to observe which also provided me some time to do some imaging with the 12-inch Sky-Watcher SkyLiner Dobsonian telescope, as well as via piggy-back on a refracting telescope.

Sunday, October 14, 2012

Celestron Omni XLT 150 R - Review

Last Saturday, the MS Astronomy students from RTU took the Celestron Omni XLT 150 R to Timberland Heights (15 mins away from Quezon City) for some stargazing in the mountains.

The telescope is a 6 inch (150mm) achromatic refractor mounted, via dove-tail, on a CG-4 German equatorial mount. It has good reviews for viewing deep-sky objects. It has a focal ratio of f/5 (focal length 750mm). The telescope makes use of the StarBright XLT coating which allows maximum light transmission. The finderscope attached is a 6x30 straight through achromat with a 7 degree field of view.

When viewing the Orion Nebula, the Trapezium stars are very well resolved and there is good contrast to the surrounding cloud layer. The stars of the Pleiades were also finely resolved.

In observing Jupiter, there is a violet halo resulting from chromatic aberration.

We also tried to do some prime focus imaging since the eyepiece holder has built-in T-threads, however the telescope requires a focal extender in order to put the image to focus. Neither planetary or deep sky targets can be focused by attaching the camera with the T-ring to the eyepiece holder's T-threads.

Saturday, October 6, 2012

Open Cluster Formation Analogy

Among the attractive celestial targets in the night sky are the star clusters. Star clusters are said to be formed in interstellar clouds when clumps of these material begin to undergo gravitational collapse. The collapsing material in turn form stars and other celestial bodies until it is consumed or blown away by stellar winds (a small amount can be retained and can be seen as nebulosity). The stars that form from a single cloud emerge as a cluster of stars. These stars either stay together in one group, or slowly drift apart from one another. This is why some clusters are very loose, while others are tightly distributed. Open clusters are important in studying stellar evolution. The stars that emerge in the cluster are typically of the same age, distance and chemical properties. In the Milky Way alone, there are roughly 1600 confirmed open clusters out of the 50-100,000 suspected. Some of the famous open clusters are the Beehive Cluster [M44], the Jewel Box,and the Pleiades cluster [M45].

A nice analogy for open clusters is the use of bubbles. Bubbles allow us to imagine the formation of stars in an open cluster. As the bubbles for in a chain of loops held together by surface tension, they resemble areas of clumped up matter - kinda like the famous "pillars of creation" image in the Eagle Nebula.
The chain eventually breaks apart and forms into individual bubble structures which we can use as an analogy for the stars. The stars/bubbles are originally confined together into a small area (tight clusters) and later spread out in space (loose cluster). Some bubbles that appear to stick together can be compared to stars that form binary pairs as a result of gravitational interaction.