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Title: Quasi-periodic Dimming of the ∼130 Myr-old Debris-Disk Hosting Star HD 240779 is not Persistent
Abstract Quasi-periodic (1.5 days) dimming (by circumstellar dust) of the 135 Myr-old AB Doradus moving group member HD 240779 was detected in photometry by TESS in late 2018. Similar observations two years later show no such signal, and ground-based photometry indicate that the signal was absent in late 2019. This suggests that the source of the dust did not survive long after 2018, e.g., it was a disrupted planetesimal, or that dust production by the body is episodic, analogous to the “evaporating” planets detected by Kepler.  more » « less
Award ID(s):
2106927
PAR ID:
10337669
Author(s) / Creator(s):
Date Published:
Journal Name:
Research Notes of the AAS
Volume:
6
Issue:
3
ISSN:
2515-5172
Page Range / eLocation ID:
49
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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