Characterizing the Infrared Variability of Protostars Using WISE and NEOWISE

We investigate the infrared variability of the scattered light nebulae surrounding 63 nearby protostars using archival data from the Wide-field Infrared Survey Explorer (WISE) telescope. The 2023 NEOWISE data release provides 18 all-sky surveys from 2010 to 2022. We conduct time-series photometry for the nebulae in bands W1 and W2 over this 12 year time period, and we consider targets with a change in flux greater than 15% to show significant variability. We detect this level of variability in 59 out of the 63 nebulae in at least one band. This variability is thought to be a consequence of the characteristics of the inner disk structure or overall changes in the source luminosity from variable accretion. In order to further investigate the causes of infrared variability of protostellar nebulae, we propose future work investigating the morphological variability of the sources with higher spatial resolutions. This work will provide further insights into the mechanisms that cause the variability that we have detected among protostellar nebulae.