The result of such a disruption may be the production of excessive amounts of related gas,dust and debris,[5] which may eventually surround the parent star in the form of acircumstellar disk ordebris disk. As a consequence, the orbiting debris field may be an "uneven ring of dust", causing erratic light fluctuations in the apparentluminosity of the parent star, as may have been responsible for the oddly flickeringlight curves associated with the starlight observed from certainvariable stars, such as that fromTabby's Star (KIC 8462852),RZ Piscium andWD 1145+017.[3][4] Excessive amounts ofinfrared radiation may be detected from such stars,[6] suggestive evidence in itself that dust and debris may be orbiting the stars.[5][7][8][9]
Tabby's Star (KIC 8462852) is anF-type main-sequence star exhibiting unusual light fluctuations, including up to a 22% dimming in brightness.[14] Several hypotheses have been proposed to explain these irregular changes, but none to date fully explain all aspects of the curve. One explanation is that an "uneven ring of dust" orbits Tabby's Star.[15][16] However, in September 2019, astronomers reported that the observed dimmings of Tabby's Star may have been produced by fragments resulting from the disruption of an orphanedexomoon.[17][18]
Consolidated plot of all known dimmings (as of 1 March 2020)
All light curve data − December 2009 to May 2013, scan days 0066 to 1587 (Kepler)
^Gary, Bruce L. (4 October 2017)."Hereford Arizona Observatory photometry observations of KIC 8462852 between 2 May and 4 October 2017".BruceGary.net. Archived fromthe original on 4 October 2017. Retrieved23 December 2017.Note: g'-band and r'-band dip depths (and shapes) may differ, with g'-band being more sensitive to dust cloud scattering due to its shorter wavelength (0.47 vs. 0.62 micron). For a reasonable particle size distribution (e.g., Hanson, 0.2 micron) the extinction cross section ratio would produce a depth at r'-band that is 0.57 x depth at g'-band. If g'-band depth is 0.3 %, for example, depth at r'-band could be 0.17 %. The "Tabby Team" measurements (Fig. 3) at r'-band are compatible with that small dip depth. Incidentally, none of these shapes resemble exo-comet tail transits; so the mystery of what's producing these week-timescale dips continues! Actually, long oval shapes are known to produce V-shaped dips (think of rings with a high inclination). – (as described by Rappaport et al, 2017link)
![One year light curve − up to 4 May 2018 (HAO[19][20][21][22])](/mt/?noimg=&dark=on&url=http%3a%2f%2fen.wikipedia.org%2fwiki%2fFile%3aKIC_8462852_Daily_Normalized_Flux_by_Bruce_Gary%2c_20170502-20180504.png)
![Light curve between 10 October 2019 and 11 January 2020 (HAO)[23]](/mt/?noimg=&dark=on&url=http%3a%2f%2fen.wikipedia.org%2fwiki%2fFile%3aKIC_8462852_October-December_2019_Gary.jpg)
