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Hi everyone, I have been observing the recurrent nova T CrB over the past few weeks in a more controlled way-capturing hundreds of 40 second exposures using a remotely accessed 10" RC and QHY 294M Pro camera and filter wheel (MSRO Station 2 telescope). Specifically, i have been concentrating on collect B band data as this is more sensitive to activity on and around the white dwarf as it accretes matter from the red giant. This star is about magnitude 10.1 in visual, but about 11.3 in the B (blue) band. When it goes nova it should briefly shine as bright as perhaps some of the stars in the Big Dipper! This was expected to have happened already, but we are still waiting. it may go at any time, or it may be another year. no one knows for sure. I have been performing this high cadence photometry in hopes of recording behavioral changes in the star that might signal an impending eruption. While nothing definite yet has occurred, I have noticed something interesting. The star has been varying between blue magnitudes 11.3 and 11.0 during my observations. The amount of flickering seen in the light curves seems more prominent when the star is brighter (near magnitude 11.1) than when at its fainter levels (mag 11.3). To help illustrate this, my friend Boris Starosta made an animated gif showing my light curves on 11 mornings from February 14 to March 10 2025 aligned so that changes from one observation to the next are easier to appreciate. This gif represents about 32 hours of continuous observing time on this star on 11 mornings. Most observing sessions were between 3-5 hours long. The graphs each have three horizontal light curves-two red and one black. the black curve is that of T CrB. The upper red line is a reference star at B magnitude 10.98. This line remains unchanged as it is a reference magnitude from which the Y-axis (magnitude) is calibrated. The bottom red light can be seen to vary in brightness slightly due to variations in seeing and instrumental effects. It can be thought of as a check against any changes seen in the target stars light curve. If changes in sky conditions cause changes in the stars brightness, these will show up as fluctuations in both the check star at the bottom as well as in the target star (black curve). However, if the bottom red line is relatively flat, but the target stars curve is varying considerably more than those changes in the curve at the bottom-it can be safely assumed the effect is real changes in brightness of the target star ( T CrB) Careful inspection shows the target star undergoes rapid changes in brightness on the order of 0.1 magnitude or greater in a matter of minutes. This is called "flicker" and is most likely due to fluctuations in brightness of the accretion disk or near-surface effects on the white dwarf itself. Flicker is seen in many stars of the dwarf-nova categories as well (SS Cyg is a good example). On this animation, note how the amount of flicker seems to be greater when the star is brighter (closer to the top red line). On some mornings when the star was closer to B magnitude 11.3-the curve was smoother with less variability. I don't know if this is a real effect, and if it is what exactly it means. But it was convincing enough for the most part for me to notice and I just wanted to put out my observations to others who may be interested in this star. Sooner or later its going to go nova, and when it does I hope to be able to look back over my light curves for clues that might be able to predict when the next nova eruption occurs in about 2105. Thanks again to Boris for putting this animation together, and I hope everyone enjoys it!

Dear RAC, MSRO user Marshall Faintich requested time on the MSRO 2 telescope recently to image M 95 in Leo. Enclosed is an "LRGB" image made using the photometric RB and V bands to simulate red, blue and green channels in the color composite. The luminance band was made by exposing with no filter in place. This image is about 3.5 hours of exposure time. Marshall pointed out to me the distant quasar J104335.9+115129 not far from the galaxy. This quasar is over 6.8 billion light years away! This has to be one of the farthest objects images at MSRO. Quasars are the intensely bright nuclei of very distant galaxies and on exposures with large telescopes look like fuzzy bluish stars. Careful inspection shows the bluish color in this image. Myron

Shout out to Troy for building me this base! Backnin business baby!

MA Stargazing Cruises stellar-events.orgI wonder if they would do group cruises? That looks like it would be a lot of fun.

Dear RAC, Perhaps someone can help ID the asteroid in the upper left part of the image. This may be 2270 Yazhi (16th mag), but my software places in outside the field of view. I have annotated the image with date and time in case anyone wants to take a stab at ID this object. the trail orientation is exactly what one would expect from a main belt asteroid. Myron

-------- Original Message -------- Subject: Astronomical League Live this Friday, March 7 at 7 pm EST Date: 2025-03-05 14:07 From: <dknabb01@...> To: "Don 01 account" <dknabb01@...> Greetings MERAL Presidents, ALCors, editors, officers, and others, I will attach a graphic announcing the upcoming Astronomical League Live show this Friday, March 7 at 7 pm EST. You can tune in using a link from the AL Facebook page https://www.facebook.com/Astronomical.League or at Explore Scientific at https://www.explorescientific.com/pages/explore-alliance-live . The show features Bob King, also known as Astro Bob. I'll be on for a short presentation on the upcoming night sky highlights. Please share this information with your club members and post the graphic on your website and social media. Clear skies, Don Knabb MERAL Chair

Hi Everyone! Spent some time last night re-imaging NGC 2276 using MSRO 2 (thanks Myron!) under somewhat more favorable conditions than my last attempt. The main issue last night was strong wind gusts. I think I see ten galaxies in this stacked image, eight of them quite clearly. I find NGC2276 to be an absolutely fascinating target with its asymmetry. Thanks! Pete Laky

Good Morning, I have started following T CrB in B band as this is more sensitive to changes in activity on and around the white dewarf. The star continues to flicker between magnitudes 11.1 and 11.3 in the B band. The spectra also is unchanged from my baseline. There was interference from high clouds during the 4 hour observation. Myron

Dear RAC and CAS, T CrB still in quiescence as of Friday morning February 21, 2025. Light curve this morning shows more flicker and a gradual brightening and dimming of about 0.1 mag most prominent in B band. This is light mostly from the white dwarf which is where the action will be from when she erupts. The star has also brightened slightly but it has done this many times before. The spectra obtained this morning is unchanged from baseline as well. Have a great day! Myron

Dear RAC, Due to cloudy weather during tonight's RAC meeting-the live observing program will not be possible. Instead, the program will be about how color images are obtained using the monochrome 294 M Pro camera. I will go through the workflow used at MSRO to convert the black and white raw images into beautiful color images. I think it will be a very instructive and interesting exercise and encourage everyone to attend if possible. We will use images tonight of the beautiful southern star cluster M 46 in Puppis. As some of you know-it has a ghostly faint planetary nebula embedded among its stars. I am including two images-a 60-second raw monochrome image taken with the V band (green) filter, and the final result obtained by stacking and combining 30 separate images (10 each using the red, green, and blue filters). Hope to see you tonight to watch how we go from one image to the final color result! Myron