ROBSERVATORY UPDATE

Over two years have past since the last image was posted.  Two issues have been at play: image quality, and automated imaging.

Image Quality:
As other astroimagers have found, there is an inherent paradox in what we do: the better one gets, the worse the outcome.  What is gained with experience is a more critical eye--since images are comprised of lengthy time exposures, and the Earth is in the habit of rotating, blurred (oblong) stars in astroimages, at first overlooked,  become the nemesis. The tracking mechanism in the telescope mount that moves the scope and camera in synchrony with the earth's rotation (and thus rendering still the object being imaged) is a metal part with manufacturing tolerances (i.e. error tolerance) of approximately the width of a human hair. More error than that, and oblong stars are the result.  This mount element has been replaced by a high quality custom part provided by Ovision (get the subtlety in the name?), located in France.  Tracking error has been thus significantly reduced and is now within acceptable limits.

Automated Imaging:
There are literally dozens of ministeps as one travels from Point A (locating an object to image) to Point B (imaging the object).  Little by little, increased intervening complexity has been layered in.  Each element was fine tuned.  Here's a verbal schematic of the steps involved in taking astrophotographs:

• Select an object to image
• move scope to the object
• take a test shot
• compare the test shot to a skychart to make sure the object is centered
• correct the position of the mount
• take another test shot>iterate this sequence until the object is in fact centered
• focus the telescope using a focus motor
• activate the filterwheel to choose a special filter which selectively passes light of specific wavelength of interest
• have a second scope track a nearby star and send tracking corrections to the mount which itself is already tracking at the rotation speed of the earth
• stop after 30 minutes and download the image
• repeat the cycle for a specified number of images
• move to the next object
•  repeat all of the above
• stop at dawn

Needless to say, the above can keep one up all night.  The latest step, however, has been to add executive software that controls and implements ALL of the above.  At this point, except for opening an closing the dome, The Robservatory is now completely Robotic.

Below is is the first, successful, completely automated image. 

For this automated image, I opened the dome and pushed one computer button.  Fifty five minutes after sunset, the equipment came alive, located and tracked the object, did all the filtering/focusing/tracking/imaging, and downloaded the images to the computer while I slept through the night.  All of the fine tuning has paid off as well: my image keep rate started at about 20%; tracking or focusing errors used to cause the remainder to be rejected.  For M97, the keep rate was virtually 100%. I'm pleased that with extensive tinkering and some relatively minor upgrades, my mid priced mount is delivering a level of precision comparable to premium mounts that typically exceed 3x the cost of mine.

The image below  is of M97, the "Owl Nebula". M97 is the exploded gas shell of a very old star. The green gas is ionized hydrogen; the blue gas is ionized oxygen.  Total exposure time was 18.5 hours.

 (Click on image to ENLARGE): 

The Soul Nebula (Click to Enlarge)

The Soul Nebula is an active region of star formation, located 6500 light years away in the Perseus Arm of the Milky Way galaxy. Ionized hydrogen gas is represented by the reddish tones, and ionized oxygen is depicted in cyan. Total exposure time consisted of 30, 30 minute images captured between October 2009 and January 2010 and combined into a single, 15 hour image. North is up.

The Bubble Nebula: (Click to Enlarge)

Blown by the wind from a massive star, this interstellar apparition has a surprisingly familiar shape. Cataloged as NGC 7635, it is also known simply as The Bubble Nebula. The 10 light-year (60 trillion mile) diameter bubble offers evidence of violent processes at work. Above and right of the Bubble's center is a hot, O-type star, several 100,000 times more luminous and approximately 45 times more massive than the Sun. A fierce stellar wind and intense radiation from that star has blasted out the structure of glowing gas against denser material in a surrounding molecular cloud. The intriguing Bubble Nebula lies a mere 11,000 light-years away toward the constellation Cassiopeia (Text courtesy of NASA/APOD)

The Rosette Nebula (Click to enlarge)

The Rosette Nebula, also known as NGC 2244, spans about 50 light-years across, lies about 4,500 light-years away, and can be seen with a small telescope. Dark filaments of dust are silhouetted by luminous hydrogen gas.Visible are globules of dark dust and gas that are slowly being eroded away by the energetic light and winds by nearby massive stars. Left alone long enough, the molecular-cloud globules will likely form stars and planets. (Text source: NASA/APOD)

IC410 in Auriga (click to enlarge)

Emission nebula IC 410 lies about 12,000 light-years away in the constellation Auriga. The cloud of glowing hydrogen gas is over 100 light-years across, sculpted by stellar winds and radiation from embedded open star cluster NGC 1893. Formed in the interstellar cloud a mere 4 million years ago, bright cluster stars are seen just below the prominent dark dust cloud near picture center. Notable near the 7 o'clock position are two relatively dense streamers of material trailing away from the nebula's central regions. Potential sites of ongoing star formation, these cosmic tadpole shapes are about 10 light-years long. (Text source: apod.nasa.gov/apod)

The Veil Nebula (Click to enlarge)

The Veil Nebula is the remnant of a supernova explosion that occurred about 5 - 10,000 years ago.
It is located 1,400 light years away in the constellation of Cygnus. (Text source: apod.nasa.gov/apod)

M27: The "Dumbell Nebula" (click to enlarge)

Known by the popular name of the Dumbbell Nebula, the beautifully symmetric interstellar gas cloud is over 2.5 light-years across and about 1,200 light-years away in the constellation Vulpecula. The hydrogen emission is seen as rust-red (H-alpha) and ionized oxygen shows up in fainter bluish hues. (Text source: apod.nasa.gov/apod)