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Is Eps Aur teasing me a bit?

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Chris Stephan
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In the last week or two, it just seems that Eps Aur is teasing me a bit, making me think it is wanting to come out of eclipse. To me, there have been a few cases where to my eye, at least, it has seemed a bit brighter, a tenth magnitude at the most. Has anyone else thought that? It's getting close to the predicted time of coming out of eclipse. Has anyone noticed anything with ccds or other sensitive instruments?

Chris Stephan
Robert Clyde Observatory
Sebring, Florida  USA

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Roger Pieri
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Hi Chris, Yes, we have seen surprising brightness variations within the past month. My observations are based on DSLR. Starting at end of january we have seen an abrupt dimming from 3.718 to 3.74 instead of the brightening expected from the OOE, then the magnitude stayed stable about3.74 for three weeks and on march 2nd and next days we gota fast brightening back to 3.713 If we extract the OOE this last jump is nearly0.1 mag within a couple of days only! Yours truly, Roger

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Roger Pieri
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Hi Chris, Tonight I just got a newresult: 3.695 SE=0.001 Under excellent sky. It seems the egress is engaged ! Yours truly, Roger

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Chris Stephan
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Roger, the last 2 nights I have observed Eps Aur at 3.7 visually. It seems to be staying just that wee little bit brighter. Im surprised we haven't heard any other comments from people on this topic, whether they agree or disagree with us. Chris Stephan Robert Clyde Observatory Sebring, Florida USA

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Hi Chris, Others from theJeff Hopkins group have seen it. They noted day-to-daybrightening similar to what I got. I should note that my absolute values are systematically brigther than most others by probably 0.02 mag but thevariations are similar. This is due to the specific color and extinction correction techniques I use, remains to determine who's right ! But, ok, what is important is the curve shape. Yours truly, Roger


Hi Chris, I asked John Clover to look in on the SMEI data and he said nothing seemed unusial, although we are ~10 days away from the predicted beginning of egress so I suppose this type of change is possible. Brian

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Hi Chris! I also observed March 1st, and I noticed it seemed to brighten up a bit aswell. I got 3.7 mag. I agree, I think it might be brightening Arwen Roussell (-:

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Chris Stephan
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I am still sensing a little more brightening in Eps Aur the past 2 nights. 3.65 magnitude estimate each night. Chris Stephan Robert Clyde Observatory Sebring, Florida USA


It's very possible. The photometrists are saying they are seeing U-B changes so the end of the eclipse is surely near!


Its always better to observe without knowing when something should happen exactly and what should or just started to happen especially if its still below the accuracy of the other visual observers. Therefore I'm the opposite of a fan of too detailed predictions in time and too early announcements on changes in light that are still not obvious to all observers. Distri- butingsuch notices too early just forces the other observers to fullfill the expectations in time and mag values. Its IMO OK to announce that something unusual happens as long as one at leasts omits to state in which direction the change happens. Being biasedcan get really a serious issue in visVSOing as this usually works sub- liminal and it can be already too late as soon the conscious thinks about what can/ should happen and the subconscious makes an unbaseddecision on it. See: http://www.citizensky.org/teams/2020-vision-team/avoiding-bias-simonsens-rules-variable-star-observing http://www.citizensky.org/forum/how-do-you-get-accurate-magnitude-estimate-visually CS Wolfgang

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