Alert Notice 727: Chandra observations taking place for RW Aur

December 6, 2020

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Further to AAVSO Alert Notice 514, Dr. Hans Moritz Guenther (Massachusetts Institute of Technology) informs us that X-ray observations have been scheduled with Chandra for the classical T Tauri star RW Aur (component A).

Chandra is scheduled to observe RW Aur as follows (the start time is given; each observation is a few hours long):

2020 December 07  09:46:50 UT
2020 December 07  21:19:40
2020 December 13  00:58:05
2020 December 15  00:00:00

Dr. Guenther requests nightly observations in as many filters as possible; time series are not necessary. Visual observations are welcome. Once the Chandra observations are over, ongoing multi-filter monitoring is requested - the campaign on RW Aur, which began in 2015, is continuing at least through 2022.

RW Aur normally varies between about 10.0 and 11.0 visually (9.6-11.2V), although it can be as bright as 9.7 and faint as 13.6. Since 2015 it has shown very interesting behavior; see the light curve from the AAVSO International Database (AID) below. As of 2020 Dec. 3.1040 UT it was 11.546 V +/- 0.014 (C. Cynamon, Mount Airy, MD) and Dec. 6.1380 UT it was visual magnitude 11.6 (E. Sawyer, Chicoutimi, QC, Canada).

Note that a light curve of RW Aur observations in the AID may be plotted using the AAVSO Light Curve Generator (

AAVSO light curve of RW Aur, June 2009 - December 2020; 8,051 multicolor observations contributed by 127 observers worldwide.

Coordinates (2000):  R.A. 05 07 49.57  Dec. +30 24 05.2 (VSX page for RW Aur)

Charts with comparison stars for RW Aur may be created using the AAVSO Variable Star Plotter (VSP).

Submit observations: Please submit observations to the AAVSO International Database using the name RW AUR.

This AAVSO Alert Notice was compiled by Elizabeth O. Waagen.

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