Sunday, April 30, 2006

Another decent night out

Last night, the seeing conditions were predicted to be so-so, about 2/5. Still, it was predicted to be clear overall, and there was going to be a visible transit of Io, one of Jupiter's moons, early in the evening. Take into consideration that I am going to be chained to my desk working on research papers for the next few weeks, I decided to head out to the local popular observing site. Just one other guy turned up. There was only one other guy there who is friendly enough and is rather comical about the whole thing. I've seen him a few times before and we get along well, and it was nice to have his company for the evening. He owns an Orion XT8i push-to telescope, which really is a first-class instrument.

Of course, my big concern tonight was aligning the scope. This was the first time I have had it out in Summer Daylight Savings time for the year, and last year I had nothing but alignment and GOTO issues during this time of year. Being prepared for the worst, I made sure to use high power eyepieces for my initial alignment procedure, and selected two alignment stars as far away from each other as possible. As it turns out, the alignment was dead-on after my first attempt, and this made for another great night of viewing. It has to be the fact that I am using a better power supply. The last one must have had a drain or leak or something. I had very good alignment all night long, the only exception being that the scope refused to put M13 in the field of view for some reason. (But it was pretty close)

So, feeling pleased again with my efforts regarding the power supply and its impact on the behavior of my scope, I took off for a four-hour tour of the heavens. The one thing I love about this hobby is that you can skip going out for a few weeks, which hurts sometimes, only to be rewarded by a refreshed night sky with new objects to look at and study. It's such a dynamic hobby.

A brief run down of my more interesting observations for the night:

- Saturn: As always, Saturn was nice tonight. The unstable air in the upper atmosphere meant waiting for a while to catch that single, nice view when it occasionally steadied. I counted about 6 moons visible, and, when the air was occasionally stable, about three cloud bands could be seen.
- M104 "Sombrero Galaxy": This was the first time I had viewed this galaxy, ever. It was very nice! I could clearly make out the central bulge, and despite so-so seeing conditions, I am pretty certain I could make out the dust lane at center. May have been my eyes playing tricks on me, though.
- M81 & M82: These two galaxies are fairly close to each other, from our perspective. With the 21mm Status, I had them both within my field of view. Again, these were new objects for me. It was really interesting to see one galaxy in a flat view (M81) and another in the "side on" view (M82).
- Virgo Cluster: I'd always read about this collection of galaxies in the Virgo constellation, but had never paid much attention to them. But, with my optics in fine collimation, GOTO working perfectly and the addition of some nice wide-field eyepieces, I checked these out. It was great fun hopping from one to another as I went through the list. Sure, they appear as smudges and not much else, but being able to view these large entities like this is just great fun.
- M13: This is my favorite globular cluster to look at, and is my second favorite item overall to observe behind M42. By 11:30PM, it was high enough to be relatively bright. The detail was just fantastic, and it's amazing to think of just how many stars are in that object. My scope portrayed lovely resolution of these.
- M5: Another globular, but a bit smaller than M13. Still, a nice object to observe.
- Jupiter: This was the highlight of the evening for me. Like Saturn, the seeing conditions made it difficult to observe Jupiter for real surface detail. Still, I watched it and kept going back to it in between viewing other objects for close to 2.5 hours. My new eyepiece (13mm Stratus) revealed lovely detail when the air settled down from time to time. The transit of Io was easily visible though, despite the bad conditions. It was quite a sight. A very clear, defined black disc on the surface of the planet, which was the shadow of Io cast onto it due to its relation to the Sun. The shadow was visible up until 11:34PM local time, and thirty minutes later, Io emerged from the side of Jupiter as a small dimple on the side of the planet's disc. This was brilliant, and I feel myself being drawn into watching these transits as often as I can. The image below is a Calsky representation of the event, but depicts what I saw last night (minus the colors, of course!). Notice the small black shadow of Io above and east of the top large cloud band.

So, overall another great night of viewing despite the ordinary seeing conditions. I think that if you persist and are willing to sit at the scope and observe an object for a long period of time, waiting for even just those few seconds when the air becomes temporarily stable, you get to see some fine images.

One final note on the Orion 13m Stratus eyepiece. I really paid attention to the performance of this eyepiece tonight, as it was the first semi-decent night that I had it out. It performed very well indeed. The field was flat to about the last 5-10% of the eyepiece field of view, where stars become just a little blurry. The rest of the field was pinpoint sharp, with no coma, ghosting etc. It performed very well on both planets and deep sky objects - M13 in particular was exceptional with the wide field of view and high level of contrast offered by the eyepiece. Orion has done very well with these eyepieces. For half to a third the price of the Televue Panoptics and Naglers, I think the value on these is just astounding. I now need to get the 8mm model!!! ;-)


ragundo said...

Great Jupiter photo.

Someday, I wish to make photos like yours, but, now witj my ETX-70 :(.

Greetings from Spain

Phil said...

Hi Ragundo,

Thanks for dropping by my blog site! Actually, the image in this post was a capture from an online astronomy program, called "Calsky". I just used it to represent what I saw the other night when Io moved in front of Jupiter.

By the way, you should be able to take very nice moon images with the ETX-70. I have seen plenty of such images taken by astronomers with that scope using either the Meade LPI camera or the Celestron Nextimage system.


ragundo said...


I realized that the photo wasn't yours just after sending the comment ;-)

Now I'm trying to do some images with a Phillips Webcam. The Meade and Celestron cameras are out of my budget right now.


Phil said...

Is that the Philips Toucam you have? A lot of folks use those to great effect. I guess if you're persistant enough you can get decent images with any system. I think it's more about how long you're willing to spend the time learning. I often just hold up my digicamera durectly against my telescope eyepiece for moon shots, it works just fine (see moonshots 2-3 posts before this post).