Friday, February 25, 2011

NGC3190 - galaxy in the Hickson 44 Group

It's a little early for "galaxy season" but this target was well placed last

For larger versions, see here:

Hickson 44 is an exquisite group of galaxies. The original image was cropped
down to this view, which is 11.1 arc-mins across (approx. 1/3rd the width of a
full moon).

This really needs about 3 hours of exposure, and much more aperture. :O)


Thursday, February 10, 2011

For users of the Celestron NexStar system

Several members of our august group have Celestron telescopes which use the
popular NexStar system. (Note that NexStar has been used as both a telescope
model and also as the name of the software that controls a variety of Celestron

I'd like to refer those members to some terrific resources that are available
that go beyond the typical user manual.

First is the Yahoo group devoted to the NexStar system (software) itself:
(Since you are already a Yahoo user, it will be easy to "Join This Group".)

Another is the Yahoo group that covers the NexStar 8 telescopes:
Notice that it also covers the 8SE telescopes and I'm sure most of this is true
for the 6SE, and others.

But probably the most comprehensive resource available for NexStar users of all
varieties is the NexStar Resource Site, produced by Michael Swanson:

It has links to everything related to the NexStar system, including the user
manuals - as well as links to Celestron
for downloading firmware updates.

If you own a NexStar telescope of any type, these resources are invaluable. Let
me know how these work out for you.

We can also review these on-line in the next meeting if anyone wishes, maybe in
the 3pm telescope clinic session.

Thanks and take care,

Bill Shaheen

Tuesday, February 8, 2011

Into the heart of Orion - M42 with 5 second exposures

Occasionally, while framing and focusing an object it helps to use short exposures (a few seconds) to expedite the process.  In doing so, bright objects such as M42, the Orion Nebula, show far greater detail since the starlight does not overwhelm the surrounding nebulosity.
In this example which combines 13 - 5 second images:

the 4 stars in the "Trapezium" are clearly resolved (discernable).

Also, notice the 2 or 3 stars to the lower left of the Trapezium. The image actually recorded the cones, depicting stellar material being blown away from the nascent stars - more commonly known for their appearance in the "Cone Nebula" (NGC2264) seen here: .

Interestingly, in the M42 image, the cones do not point directly away from the Trapezium. Is there possibly an even larger brighter star, or stars, hidden behind the dust to the left of the Trapezium?

Bill Shaheen
Superstition Mountain Astronomical League
Gold Canyon, AZ

Update: 23-Feb-2011

I am pleased to report that I have resolved the question of what appeared (to me at least) to be light cones in the heart of the Orion Nebula.

Last evening, I imaged the area under investigation using a hydrogen alpha filter and without binning, i.e., higher resolution. It is much more apparent to me now after reducing the star halo that what appeared to be the right side of a cone is afterall a separate feature.

Here is the original image that prompted my question:

Here is the Ha image from last night:

And here is a side-by-side comparison with the area highlighted:

It seems rather obvious now that what looked to me to be the illuminated right side of a light cone is actually a separate feature, and may in fact reside in the foreground.

This demonstrates the advantage of using higher resolution imaging and the use of narrow-band filtering to reveal the true detail.  And, of course, that appearance can indeed be deceiving.

Thanks for looking,

Bill Shaheen
Superstition Mountain Astronomical League
Gold Canyon, AZ

Friday, February 4, 2011

Meteor caught on video

This happens every so often. While the autoguide camera is guiding on a star, a
meteor comes along. Well, this time I was ready for it and had the recorder
queued up with my finger over the record button.
(Happens in the last couple seconds.)

I've even had geosynchronous satellites drift by. Well, actually, the satellite
is stationary but since the telescope is tracking the stars, they appear to
drift by. I'm actually trying to locate a geo satellite and test using it as a
collimation star.

Brings to mind another idea - have recording software running on a loop that
keeps just the previous 15 minutes or so in order to not miss the beginning of the meteor's appearance.