The History of the Mysterious Eclipses of KH 15D: Asiago Observatory, 1967-1982

2003/12/23 by John Asher Johnson, John A. Johnson, Joshua N. Winn · 4 citations
Physics and Astronomy · #Astrophysics and Star Formation Studies #Solar and Space Plasma Dynamics #Stellar, planetary, and galactic studies #astro-ph

paper · pdf · doi:10.1086/382520

Accepted to AJ. 24 pages, 10 figures, 2 tables. v2: Phase error corrected in figures 8 and 10

arxiv created 2003/12/23 · openalex publication_date 2004/04/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31

Abstract

We are gathering archival observations to determine the photometric history of the unique and unexplained eclipses of the pre–main-sequence star KH 15D. Here we present a light curve from 1967 to 1982, based on photographic plates from Asiago Observatory. During this time, the system alternated periodically between bright and faint states, as observed today. However, the bright state was 0.9 mag brighter than the modern value, and the fractional variation between bright and faint states (Δ I = 0.7 mag) was smaller than observed today (3.5 mag). A possible explanation for these findings is that the system contains a second star that was previously blended with the eclipsing star but is now completely obscured.

Cited by

• KH 15D: A Spectroscopic Binary
• The Peculiar Periodic YSO WL 4 in ρ Ophiuchus
• THE Ĝ SEARCH FOR EXTRATERRESTRIAL CIVILIZATIONS WITH LARGE ENERGY SUPPLIES. IV. THE SIGNATURES AND INFORMATION CONTENT OF TRANSITING MEGASTRUCTURES
• THE LIGHT CURVE OF THE WEAKLY ACCRETING T TAURI BINARY KH 15D FROM 2005-2010: INSIGHTS INTO THE NATURE OF ITS PROTOPLANETARY DISK