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Notes from the telescope- May 2012

SXN's picture
Joined: 2010-03-12

Last night and this morning were just gorgeous here in Michigan. A cool, calm, moonless night with good seeing and transparency- it doesn't get much better.

I started the night doing my Chinese fire drill routine, monitoring CVs for outbursts until about 2AM. Then I took time out to visit some old LPV friends in Hercules.

R Her was first up. I really had to dig hard to see it. The 10mm Ethos at 300x did the trick. It is near minimum right now. I called it 15.0. This sequence is actually pretty good, but it could use a comp or two fainter than 14.9. If it had been hazy or the moon had been up, I doubt I would have seen it.

A few other LPVs in Her have issues with the sequences. I can't wait for APASS to finally fill in this region of the sky for the chart team. Hercules has a lot of great stars, but some of these sequences are poor. SS Her was a tough call. I made it out to be 10.0, but I had to exclude the 102 comp from my estimate because it looked too faint to my eye. So I used the 104 and 95, which is a pretty big gap. This one is a pretty interesting customer. It has maxima that seem to vary between either 10.0 or 8.5. It has a relatively short period of 107 days, so you get to see lots of action in a season. I don't think you can over-observe this one.

W Her presented a bit of a challenge too. There is an incovenient gap in this sequence between 124 and 133, so naturally, that is exactly where I needed to make the call last night. I called it 12.7, and that seems to fit the light curve perfectly, but I wasn't near 100% confident at all on that estimate. More like 80%.

Later on I ran into another gap even larger. RV Her has a gap in the sequence between 100 and 112! That is simply too many steps to subdivide in my mind's eye to make an estimate. I prefer 0.2-0.5, but I can deal with up to around 0.7 in a pinch. Anything greater than that and my confidence drops significantly. This is another one of those Miras that has maxima that swing between 9.5 and 10.5. I called it 10.5 this morning, but the light curve is pretty sparse. It's on the rise, but is this max or will it go up to 9.5? 

RT Her was a nice challenge. It was faint, around 14.3. Luckily it sits alone forming a nice elongated triangle with a 140 and a 146 comp. So once you pick it up and can see the 146 you're in business. A couple weeks ago this bugger was down around 15.5, so I was covering it with K35 on AAVSOnet. Its on the rise, so now is a good time to pick it up.

TV Her was faint, and quite a challenge at 14.8. All in all it was a satisfying session. Tonight I plan to do UMa and Dra as well as Lyra LPVs. That ought to keep me busy for hours.

What are you observing?

Observing Strategy
robinriordan's picture
Joined: 2011-03-02

I plan my observing based on a couple of criteria. I select program stars that are within a relatively small region of the sky. Typically, this means one or two adjacent constellations. I use a Meade LXD 75 Schmidt Newtonian with a CCD that has a field of 17 x 21 arcmins. Small slews help me avoid getting lost among the stars. I also restrict myself to either the east or the west on a given night. The meridian flip with my GEM requires that I go out to the telescope and visually acquiring my target. I guess that it is obvious that I operate my telescope remotely from the warmth of my study. Although the mount is perfectly polar aligned, the autostar guide system is simply not up to the task. I do deviate from this procedure when Mike publishes the Inner Sanctum stars for the month. I reserve a couple of nights to capture those denizens of the deep.

I might mention that George Silvis has released version 8 of PhotomCap which reads the newly formatted photometry data pages. You can retrieve this from:

I find this software to be a real time saver for entering data into AIP4Win. As I mentioned in a separate post, I am paying close attention to the V Lyr field. I seem to have lost track of 3UC 240-158111, a star from the UCAC3 catalog which is V=13.69 and B-V=0.00.,Apparent RA: 19h09m41.478s DE:+29?39'49.34". This reminds me of Luke Skywalker losing a planet.

Any and all comments and recommendations are welcomed.

Hope we all enjoy good seeing.

Robin RROA

lost star
HQA's picture
Joined: 2010-05-10

Hi Robin,

I'm not sure you have the right name or position.  3UC 240-158111 is located at

19 09 10.818 +29 38 42.32

with a magnitude of 13.43

No star is located in any catalog at the position that you mention:

19:09:41.478 +29:39:49.34


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