Dip update 9/n
[Orig: June 14, 2017]
Today was my first day back in the office after two weeks of traveling, you can imagine what its been like. I will keep this note brief and share the news of an interesting event that started this week. It started with observations from the Trappist telescope taken the night of June 11, which indicated a small, but abrupt decline in the stars brightness. Their observations were densely sampled, spanned only a few hours, and had impeccable precision. These are the TRAPPIST observations (courtesy of Khalid Barkaoui, PhD student):
Data from LCO and several other observers who were taking data at that time couldn't verify this claim with significance -- the decline in brightness was too shallow for the precision of the data.
However, the following couple nights proved fruitful. We were able to see a drop across many observatories. As of last night, the drop remains 1%. Below is a graph of the latest. You can see at the bottom of the graph around day 6 the points are low (there are also fewer of them, thanks to Mother Nature). Even though they are low, they are still consistent (within the error bars) of the points to the left where the star is normal brightness. This is what we mean when we say "not significant". In fact, the first single point point just to the left of day 6 is likely just noise, i.e., the stars brightness is 'normal' at this time.
However, the most recent observations remain on a downwards trend to where we are today. Confidence at this level is difficult, but I can assure you that we waited until it was confirmed by several observers before claiming it being significant.
We eagerly await what tonight will bring. If we reach several percent again, we will send out another alert. Right now, at 1%, it can go either way.
~Tabby and team